On the reliability of visual communication in vertebrate-dispersed fruits

  • Eliana Cazetta,

    Corresponding author
    1. Departamento de Ecologia, Universidade Estadual Paulista – UNESP, C.P. 199, 13506-900 Rio Claro, SP, Brazil
      Correspondence author. Departamento de Ciências Biológicas, Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna km 16, Ilhéus, Bahia, CEP 45662-900 Brazil. E-mail: eliana.cazetta@gmail.com
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  • Mauro Galetti,

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  • Enrico L. Rezende,

    1. Departament de Genètica i de Microbiologia, Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
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  • Hinrich Martin Schaefer

    1. Faculty of Biology, Evolutionary Ecology, University of Freiburg, Hauptstr. 1, 79104 Freiburg, Germany
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1. Several fundamental aspects of communication between plants and their mutualists are poorly understood. It remains unclear whether plant signals are accurate and reliable, that is, whether they recruit mutualists by informing them about the nutritional rewards provided by flowers and fleshy fruits.

2. We evaluated fruit characteristics of 105 vertebrate-dispersed species from an Atlantic rainforest community to examine the relationship between visual fruit stimuli and fruit quality. We combined morphological, biochemical and spectrophotometric methods and employed comparative analyses to assess the evolutionary association among morphological, biochemical and visual characters.

3. We detected a significant phylogenetic signal in most morphological and nutritional traits but not in colour traits, which suggests that fruit colours are evolutionarily labile. We also found that two properties of fruit coloration (brightness and chroma) explain 24–29% of variation in protein and sugar contents, respectively. High sugar content in fruit is associated with dark colour and low chroma (colour saturation). However, fruit brightness is not strongly correlated to protein content and its signalling role remains unknown.

4. We suggest that the negative relationship between chroma and sugar content in fruit can be explained by the fact that sugars up-regulate the synthesis of anthocyanins, the pigments primarily imparting achromatic coloration in fruits. Biochemical pathways could consequently explain the covariance between visual fruit traits and nutritional fruit traits. In this scenario, information could arise as by-product rather than as an adaptation to signal to seed dispersers.

5.Synthesis. We show that fruit visual traits are evolutionary labile and that fruit chroma and brightness can reliably indicate sugar and protein content, respectively. We propose that shared biochemistry is a likely mechanism inducing the covariance between colour (the stimulus) and nutritional quality (as the unseen quality). We hypothesize that by-product information represents a widespread and so far neglected mechanism leading to reliable visual traits in mutualistic and possibly also antagonistic plant–animal interactions.

To overcome the constraints imposed by immobility, many plants produce conspicuous flowers and fruits to recruit animal vectors for reproduction and dispersal. In accordance with the widespread evidence that animals use colour and odour to find plant rewards, the colours and bouquets of flowers and fruits are thought to have evolved primarily or secondarily as communicative traits facilitating the recruitment of mutualistic animals. However, the fundamental mechanisms by which plants communicate with their mutualists remain contentious, particularly because defining communication is generally a controversial subject. The process of information transfer is key to many definitions of communication (e.g. Bradbury & Vehrencamp 1998), while others suggested that communication is not necessarily informative (i.e. transferring accurate information) but should instead be considered as a process of influencing or manipulating others (Dawkins & Krebs 1978; Maynard-Smith & Harper 2003; Rendall, Owren & Ryan 2009; Scott-Phillips 2010).

The reliability of plant–animal communication – apart from when indicating the location of a plant – is not well known. This uncertainty is surprising because plants are an ideal system to evaluate the reliability of this information because plant displays are relatively constant in space and time; they are often less complex and dynamic compared with animal displays and lack a movement component (Schaefer, Schaefer & Levey 2004). In contrast to animal communication where the interests of senders and receivers can quickly change (e.g. depending on the dynamics within social groups), it is also easy to define the potential information content of plant traits because animals’ interest in plant nutritional quality is relatively invariant and predictable. Clearly, animals can select for reliability, that is an accuracy between signal and reward (Armbruster, Antonsen & Pelabon 2005; Benitez Vieyra et al. 2010). However, fruit colours can also be strongly determined by selection by antagonists or abiotic factors (Strauss & Whittall 2006; Schaefer, Rentzsch & Breuer 2008; Schaefer & Braun 2009; Steyn et al. 2009), and it is unknown whether these selective regimes produce reliable communication between plants and animals.

There are currently two major limitations in the field of plant–animal communication that limit progress in the field. First, the correlations between colours (and likewise odours) as sensory stimuli that animals perceive and the nutritional qualities of plant rewards are mostly unknown. Only very few studies analysed whether colour traits are reliable on a community level. Schaefer & Schmidt (2004) found that fruit colours in the Venezuelan rainforest indicated fruits’ nutritional contents. Similarly, Raine & Chittka (2007) reported that violet was the most rewarding floral colour in a plant community in Germany and that bumblebees have an innate sensory bias towards violet. The second limitation is that these studies did not control for phylogenetic effects on fruit or flower colours, even though such effects strongly influence morphological and nutritional traits of plant reproductive organs (Herrera 1992; Jordano 1995). The lack of a phylogenetic perspective on the relationship between the colours of fruits and flowers and the nutritional rewards associated with them precludes an understanding of the evolutionary history of the covariance between those traits. Moreover, many comparative studies have shown that species are often not the appropriate sampling unit because traits do not evolve de novo in response to the current selective pressures in each species (Fischer & Chapman 1993).

To study the relationship between fruit stimuli and fruit quality, we evaluated morphological, biochemical and visual fruit traits in a large data set (105 species) from a phylogenetic perspective in an Atlantic rainforest community in Brazil. If fruit traits are reliable, we expect colour and morphology to indicate fruit nutritional quality. Fruits can contain both palatable and unpalatable components. In general, secondary compounds (responsible for fruit unpalatability) have complex functions in ripe fruits, and according to the most influential hypothesis, there may be a trade-off between defence against damaging agents and palatability for dispersers (Herrera 1982; Cipollini & Levey 1997). In the context of plant–animal communication, we thus expect information to similarly represent a trade-off between attracting visually oriented dispersers and fending off visually oriented fruit predators. Specifically, we predict that if seed dispersers have primarily influenced fruit communication, fruit colours should indicate the contents of nutrients such as carbohydrates, lipids or proteins. In the discussion, we consider the proximate mechanisms underlying the observed covariance among visual and nutritional traits and contrast the scenario of adaptive, reliable fruit communication to seed dispersers against a scenario of nonadaptive, reliable fruit communication.

To assess the evolutionary association among fruit characters, we tested whether the covariance among traits exhibits a phylogenetic signal by employing comparative analyses. We specifically evaluated whether any correlations among colour and morphology and fruit nutritional contents are associated with phylogeny or independent of it. We further tested whether fruit colour is an evolutionary conserved trait differing among higher plant taxa or whether it is an evolutionary labile trait that may adapt to different selection regimes. In our large data set, fruits were mainly dispersed by birds and primates. In our phylogenetically explicit analyses, fruit colour traits need to be assigned unambiguously. Hue, chroma and brightness are three colour properties that provide such unambiguous notation (Endler 1990). They are therefore the most commonly used colour variables in comparative studies (Montgomerie 2006). These three colour variables account for primate vision. To account for bird vision, we also included in our analyses the chromatic contrasts between fruits and their background, as seen by birds. Thus, this approach would allow us to assess the detectability and reliability of information transmitted by fruit visual stimuli.

Materials and methods

Study system

Fruits were collected at Ilha do Cardoso (25°03′ S and 48°53′ W), a pristine land-bridge subtropical island, located in the south of São Paulo state, Brazil. The study site is a 15 100 ha protected island composed exclusively of Atlantic rainforest, including lowland and highland tropical rainforest, mangroves, dune vegetation and restinga forest (Barros et al. 1991). The climate at Ilha do Cardoso is generally warm and wet throughout the year, with a mean annual rainfall of roughly 3000 mm and average ambient temperature of 23.8 °C (Funari, Struffaldi-De-Vuono & Salum 1987; Castro, Galetti & Morellato 2007).

We collected quantitative information on fleshy fruit traits for 105 vertebrate-dispersed species belonging to 44 families (see Appendix S1 in Supporting Information). The sample was dominated by trees (59 spp.), followed by shrubs (29 spp.), vines (eight spp.), herbs (five spp.), hemiparasites (two spp.) and bromeliads (two spp.), and represents c. 50% of the known vertebrate-dispersed plants in the area (E. Cazetta unpublished data). Fruits from these species are mainly dispersed by birds (74 spp.), followed by mixed agents (birds and primates as well as other mammals; 15 spp.) and primates and other mammals (16 spp.) (Appendix S1), which is a common pattern found in vertebrate-dispersed plants in the Atlantic forest (Almeida-Neto et al. 2008).

Fruit phenotypic traits

For each species, we collected c. 30 ripe fruits (range 8–50) from at least three individuals per species (for some species, we obtained fruits from up to five individuals). From these samples, we obtained data on fruit morphology, chemical composition and colour. Due to logistic constraints, sample sizes varied depending on the type of measurement: morphological variables were measured in all species (= 105 spp.), whereas fruit colour and chemical composition were obtained from smaller subsets of the total (= 58 spp. and 78 spp., respectively). Therefore, we report the total number of species or the degrees of freedom of each analysis.

Fruit morphology

Morphological traits were measured on 30 fruits per species. For each fruit, we quantified the following variables: length and diameter of the fruit and its seeds, fruit fresh mass, pulp fresh and dry mass, seed mass and number of seeds per fruit. From these measurements, we also calculated the relative yield of fresh fruits (dry mass of the pulp/fresh mass of whole fruit) and the pulp to seed ratio (dry mass of pulp/mass of the seeds).

Colour measurements and contrast calculation

To estimate fruit colour, we measured the reflectance spectra of 15 fruits per species, as well as 10 leaves and 10 accessory structures (nongreen pedicels, capsules) if present. We performed all measurements with an Ocean Optics USB2000 spectrometer and a Top Sensor System Deuterium-Halogen DH-2000 (both Ocean Optics, Duiven, the Netherlands) as a standardized light source. Fruit reflectance was measured as the proportion of a standard white reference tile (Top Sensor Systems WS-2). We calculated three variables that characterize reflectance spectra: total brightness, chroma and hue (Endler 1990). Brightness is the intensity of reflected light from a given surface and is measured as the cumulative sum of the light intensity reflected (R) between 300 and 700 nm. Variation in brightness is perceived on the scale of white to black. Humans (and presumably other primates as well) perceive chroma and hue as chromatic aspects of visual information. Chroma (or saturation) describes the colours’ similarity to a neutral grey; colours that contain no or very little grey are deeply saturated, whereas a grey with a little tint of colour has a low saturation (see Kelber, Vorobyev & Osorio 2003 for a thorough review). Chroma is calculated as reflectance variation between 300 and 700 nm ((RmaxRmin)/Raverage). In contrast, hue defines colour differences that are related to human colour categories, for example red, yellow and green. While there is no evidence that animals other than primates perceive hue and chroma as humans do, some experiments on chickens suggest that they can categorize colours in a way similar to humans (Jones, Osorio & Baddeley 2001). Hue (or spectral shape) is measured as the wavelength of maximal reflection (λ(Rmax)).

The visual system of our two most important seed disperser groups, birds and primates, differs with birds being superior in discriminating colour differences (Håstad & Odeen 2008). We selected the three variables that characterize colour properties that primates can extract from visual stimuli and that are also likely to be perceived by birds because they have superior visual abilities. To account specifically for avian vision, we calculated additionally chromatic contrasts between the mean reflectance of fruits and leaves or secondary structure according to eye models of avian vision (Vorobyev & Osorio 1998). The model first calculated the quantum catch of each class of single cones presented in a tetrachromatic visual system (LWS, MWS, SWS and UVS), based on analytical approximation of cone visual pigments and oil droplet spectra. The quantum catches are used to find relative contrasts against fruits and background. Contrasts were characterized in units of ‘just noticeable differences’ (jnd), following the model proposed by Vorobyev & Osorio (1998). One jnd is the threshold of discrimination; higher values indicate discrimination of two colours. For example, we found on Ilha do Cardoso that increasing fruits’ contrasts also increases fruit detection by birds up to a threshold of 40 jnds (Cazetta, Schaefer & Galetti 2009). We opted to employ this model because most dispersers in Ilha do Cardoso are birds, and our previous study showed that birds attend primarily to chromatic contrasts to locate fruits in this community (Cazetta, Schaefer & Galetti 2009).

Chemical analyses

To estimate fruit chemical composition, the pulp or aril from fruits was frozen at −18 °C following collection, until the moment of analysis. For each fruit sample, we ran three replicates and used the mean of the three values for statistical analyses. The following variables were estimated from chemical analyses: protein composition, lipid content, total soluble sugar content and secondary compounds (phenols).

Proteins were determined with the Kjeldahl method, which consists in estimating total nitrogen in the fruit as a surrogate for total protein (protein composition was calculated by multiplying total nitrogen by 6.25) (Jeffery et al. 1989). This conversion factor may overestimate the total amount of protein found in fruits, but it does not alter conclusions on the covariance between protein contents and fruit visual traits. Lipid content was determined employing the standard macro-gravimetric method (Bligh & Dyer 1959). Total sugar content (glucose + fructose + sucrose) was estimated with gas chromatography–mass spectrometry (GC–MS), because the interference of coloured material in fruit pulps or arils prevented the use of more standard colorimetric methods (e.g. the Anthrone method; see the study by Pooter & Villar 1997).

To determine the content of secondary compounds (phenols), we employed the extraction method proposed by Price & Butler (1977), employing butanol and methanol extracts (see details in the study by Schaefer, Schmidt & Winkler 2003). Although not all phenolic compounds have similar extraction probabilities, this index of phenolic compounds correlated negatively in our community with the consumption of fruits by birds and fruit pathogens alike (Cazetta, Schaefer & Galetti 2008), demonstrating that this index is biologically meaningful. We focused on phenols because they commonly occur in fleshy fruits, and they are the most widespread secondary compounds in ripe fruits (Buren 1970; Herrera 1982; Cipollini & Stiles 1992; Foley, McLean & Cork 1995). The contents of these compounds were analysed with photometric measurements (for details, see the study by Cazetta, Schaefer & Galetti 2008).

Statistical analyses

We reconstructed the phylogeny of plant species from Ilha do Cardoso with the Phylomatic software, employing the Phylomatic conservative supertree (Webb & Donoghue 2005). We analysed the phylogeny of fruit traits to evaluate to what extent our results on trait covariances are influenced by phylogeny. It was not our principal aim to study the evolution of fruit traits given that our sample did not comprise an adequate and balanced sample within the phylogeny. Because estimates of divergence times were not available, we tested four different arbitrary branch lengths: constant branch lengths (all branch lengths = 1), Grafen (1989), the variant Nee’s (Purvis 1995) and Pagel (1992). Statistical adequacy of the different branch lengths were tested by plotting the absolute values of standardized phylogenetic independent contrasts against their standard deviations, and branch lengths were considered statistically adequate if there was no correlation between these values. In essence, this means that there is no consistent bias as a function of divergence times during the calculation of contrasts (i.e. contrasts are uniformly distributed across long and short branches); hence, the standardization procedure can be considered adequate for statistical purposes (Garland, Harvey & Ives 1992). These analyses were performed with PDTREE (available in the PDAP package; Garland et al. 1993), employing log10-transformed phenotypic values to improve normality, except for sugar content which was square-root-transformed. Because we were interested in performing analyses employing a single phylogeny, we selected Nee’s arbitrary branch lengths transformed with Grafen’s rho of 0.5 (see Results), which was statistically adequate for all studied phenotypic variables.

To investigate whether fruit morphology, chemistry and colour of the plant species in Ilha do Cardoso show significant phylogenetic signal, and whether this signal differs between these suites of characters, we employed the randomization procedure of the matlab program Physig.M developed by Blomberg, Garland & Ives (2003). This method consists in shuffling tip values across the real phylogeny and obtaining the distribution of variance in contrasts under this null model. If the variance of the real data set is lower than 5% of the values obtained from the randomizations (1000 in our study), we rejected the null hypothesis of no signal with < 0.05. We also compared the k-statistic obtained in each analysis, which describes the amount of phylogenetic signal in the continuous-valued traits and allows for comparisons across phylogenetic trees and phenotypic traits (Blomberg, Garland & Ives 2003). A value of 1 indicates exactly the amount expected under Brownian motion evolution along the specified phylogeny (topology and branch lengths). Values smaller than 1 indicate less phenotypic resemblance between relatives than expected and larger than 1 indicate stronger than expected phylogenetic clumping of trait values.

We performed Pearson’s correlations to test for pairwise associations between visual cues and estimates of fruit quality and defence to document the covariance among phenotypic fruit traits. Importantly, animals may combine a set of indicators rather than base their decisions during foraging on pairwise correlations only. Multivariate analyses may thus be more adequate. Therefore, we analysed the relation between macronutrients and phenols employing a model comparison approach. In this context, we were primarily interested in determining the association between fruit morphology, colour and nutrients, and we evaluated whether visual cues such as colour and morphology are good indicators of fruit quality, as judged by its chemical composition. While regular correlation and regression analyses are adequate to test whether dispersers can rely on visual cues to select better fruits, phylogenetically informed tests are generally more adequate to address if traits at different levels of organization have coevolved in response to selection.

Subsequently, we used the matlab program RegressionV2.M (Lavin et al. 2008) to perform linear statistical models via both ordinary least squares (OLS) (i.e. nonphylogenetic) and phylogenetic generalized least square regressions (PGLS) (Garland & Ives 2000; Garland, Bennett & Rezende 2005). Ordinary least square regressions assume that the unexplained residual variation is independent among species, while PGLS assumes that residual variation among species is correlated, with the correlation given by the degree of phylogenetic relatedness between species. We used both approaches to understand whether relationships among fruit traits are evolutionary conserved (and thus better explained by PGLS models) or evolutionary labile (and thus better explained by OLS models).

Regression models included chemical compounds (lipids, sugar, proteins and phenols) as the dependent variables and fruit morphology and colour as independent ones. Because morphological traits were highly correlated, we first performed a diagnostic principal component analysis and selected the variables that explained most of the variance in our data based on the score values (data not shown). Therefore, the morphological variables we selected were fruit diameter, seed number and relative yield. We included these variables even though the relative yield of fruits or the number of seeds is not involved in signalling. However, fruit consumers may learn that some fruits are relatively unrewarding and thereby use colour or other external stimuli (fruit size and shape) to avoid these fruits. The colour variables included in the model were brightness, hue, chroma and fruits’ chromatic contrasts as seen by birds.

We compared models including morphology or colour as independent variables employing the Akaike Information Criterion (AICc, which corrects for small sample sizes; Turkheimer, Hinz & Cunningham 2003), using the smaller-is-better formulation. When comparing a series of models, the one with the lowest AICc is considered to be the best. We also calculated the Akaike weights (wi) that are particularly intuitive because they may be expressed in terms of percentage and can be interpreted as ‘weight of evidence’ in favour of the model with the lowest AICc when compared with all alternative models (Turkheimer, Hinz & Cunningham 2003). Comparisons between models allowed us to determine (i) which visual cues can be employed as accurate indicators of fruit quality and (ii) whether the inclusion of phylogenetic information significantly improves the fitness of the tested regression models. We did not employ Bonferroni corrections in this analysis because this approach can be very conservative in the context of model comparison (Burnham & Anderson 2002). Instead, we opted to report relations that were significant with a < 0.05 weighed by the evidence provided by different models. That is, if a given relationship is statistically significant in more than one model, the total weight of the evidence favouring a significant relationship corresponds to the Akaike weights wi summed across models.

Phylogenetic signal

Our working phylogeny, based on the diagnostic test suggested by Garland, Harvey & Ives (1992), presented little hierarchical structure. The branch lengths that showed better adequacy for all traits were Nee’s arbitrary branch lengths, subsequently transformed with Grafen’s rho of 0.5 (Fig. 1). Randomization tests suggest that most morphological and chemical traits exhibit significant phylogenetic signal, except for pulp fresh mass and sugar content (Table 1). Conversely, we did not detect phylogenetic signal in colour traits and phenols. The k-statistics revealed that the amount of signal is lower than expected by Brownian motion for all studied traits (Table 1). This result, concomitantly with the low degree of hierarchy of our working phylogeny (i.e. where most of the phenotypic variation is explained by recent history, and not by shared evolutionary history deeper in the phylogeny), suggests that phylogenetic signal in fruit characteristics in the plant community of Ilha do Cardoso is generally weak, in spite of being significant in many instances (Table 1).

Figure 1.

 Phylogenetic hypothesis employed to analyse the vertebrate-dispersed species at Cardoso Island, Atlantic rainforest (Brazil), including some representative plant orders belonging to this community. Randomization analyses were employed to test whether fruit morphology, chemical composition and colour showed significant phylogenetic signal, which is illustrated by the clustering of values below (black bars) and above (white bars) the median, shown by the triangle at the bottom of the panels. Generalized linear models were subsequently employed to test whether visuals cues were accurate indicators of fruit quality. The species and the data sets analysed are provided in the Supporting Information.

Table 1.   Range of phenotypic values observed for fruits from the community of Ilha do Cardoso and phylogenetic effects
 Phenotypic traitObserved rangenPearson rkP
  1. The number of species (n), results from diagnostic tests of branch length adequacy for Nee’s branch lengths with 0.5 rho transformation (Pearson’s r), the amount of phylogenetic signal (k) and its significance according to the randomization tests are listed for each phenotypic trait. Values in boldface are significant at P < 0.05.

MorphologyFruit diameter (mm)3.8–35.41050.11340.75110.044
Fruit length (mm)3.7–43.91050.06530.77980.017
Fruit fresh mass (g)0.02–23.411050.23610.77020.027
Pulp fresh mass (g)0.01–19.991050.28770.73580.076
Pulp dry mass (g)0.001–8.091051.84120.8643<0.001
Seed diameter (mm)0.4–27.91050.36500.8963<0.001
Seed length (mm)0.6–40.11050.42510.87320.001
Seed number (#)1–c. 5401050.50630.9214<0.001
Seed mass (g)0.002–13.841050.33910.82220.004
Relative yield0.003–0.4931050.00170.80650.003
Pulp/seed ratio0.04–4401050.06330.82750.005
Chemical compositionLipids (%)0.29–83.3781.55390.90960.001
Proteins (%)2.08–18.30780.87040.83910.023
Sugar (%)<0.001–3.76780.05890.78310.077
Phenols (%)0.50–8.22780.27440.76680.074
ColourBrightness (QT)0.77–3118.6580.50570.79980.082
Hue (nm)335.0–695.0580.16480.71870.419
Chromatic vision (jnd)5.40–155.03580.02190.76030.181

Visual cues and chemical composition

Results from correlation tests and regression models designed to determine whether fruit morphology and colour could be employed as reliable indicators of fruit composition and quality varied depending on the nutrients analysed. Pairwise correlations between visual cues and chemical composition suggested that chroma may be employed to assess fruit sugar content (two-tailed < 0.05). Pairwise correlations also indicated that the relative yield of fruits was positively correlated with lipids and negatively correlated with proteins (Table 2), which means that fruits with high lipid values contain a large amount of pulp, while the opposite is true for protein-rich fruits. Multivariate analyses were used because animals may combine a set of indicators during foraging. Also, if seed dispersers tend to choose fruits based on their phenotypic attributes, their choice may also show a degree of phylogenetic structure (if they choose closely related species based on phylogenetically conserved cues).

Table 2.   Pairwise regular Pearson’s correlations between fruit characteristics and chemical composition
 Fruit sizeSeed numberRelative yieldBrightnessChromaHueChromatic contrast
  1. Correlations performed between log10-transformed data, except for sugar that was square-root-transformed to meet normality.

  2. *Two-tailed < 0.1, **two-tailed < 0.05.

Lipidsr76 = −0.138r76 = −0.155r76 = 0.224r45 = 0.167r45 = 0.220r45 = 0.145r45 = 0.145
P = 0.228P = 0.175P = 0.048**P = 0.262P = 0.137P = 0.330P = 0.330
Proteinsr76 = 0.166r76 = −0.006r76 = −0.223r45 = 0.247r45 = −0.041r45 = −0.080r45 = 0.125
P = 0.146P = 0.959P = 0.049**P = 0.093*P = 0.783P = 0.593P = 0.402
Sugarsr76 = 0.0025r76 = −0.0084r76 = −0.074r45 = −0.086r45 = −0.296r45 = 0.039r45 = −0.110
P = 0.982P = 0.942P = 0.516P = 0.566P = 0.043**P = 0.794P = 0.460
Phenolsr76 = −0.035r76 = −0.130r76 = 0.196r45 = −0.172r45 = 0.035r45 = 0.246r45 = −0.029
P = 0.764P = 0.255P = 0.085*P = 0.248P = 0.813P = 0.095*P = 0.846

Overall, regression models including fruit colour, but not fruit morphology, were the best predictors of sugar concentration, protein content and concentration of phenols, as judged by lower AICc values and Akaike weights wi that were nearly three times larger than models including morphological traits (Table 3). Thus, two variables employed to characterize fruit colour (brightness and chroma) were indicative of different aspects underlying fruit composition in these models, while fruit hue and the chromatic contrast perceived by birds did not indicate fruit composition. Brightness was associated with protein content with a < 0.05 in the two best models that, taken together, support a significant association between these variables with a total Akaike weight of 71.7 (Table 3). The positive relation between fruit brightness and protein content indicates that bright fruits (e.g. yellow and white ones) in this community apparently contain more protein than darker fruits (Fig. 2). Similarly, the Akaike weight of 64.47 indicated that the best model of sugar content is negatively associated with the chroma of fruits, meaning that fruits with low saturation, such as black fruits, have higher sugar contents than strongly saturated fruits (Fig. 2). The discrepancy between the Akaike weights of the OLS and PGLS models on sugar content is consistent with a lack of phylogenetic structure on sugar contents (see Table 1).

Table 3.   Results of regression models testing for the relation between fruit morphology, colour and chemical composition
 ModelRegressionAICcF statistic
wiFruit sizeSeed numberRelative yieldBrightnessChromaHueChromatic contrast
  1. Results from ordinary and phylogenetic generalized least square regressions (OLS and PGLS, respectively). Significant results (< 0.05) are highlighted in boldface. AICc is the Akaike Information Criterion corrected for small sample sizes and wi is the Akaike weight. All models with a low likelihood of being the true model (wi values <0.2) were nonsignificant, and F values were omitted.

PGLS74.7349.60F1,43 = 1.654F1,43 = 0.078F1,43 = 1.540
PGLS76.3222.40   F1,42 = 2.691F1,42 = 3.674F1,42 = 0.030F1,42 = 0.547
ColourOLS−14.1328.95   F1,42 = 4.425F1,42 = 0.004F1,42 = 0.300F1,42 = 2.703
PGLS−14.9142.75   F1,42 = 4.223F1,42 = 0.123F1,42 = 0.103F1,42 = 2.777
ColourOLS91.2864.47   F1,42 = 2.468F1,42 = 4.651F1,42 = 0.027F1,42 = 0.900
PhenolsMorphologyOLS7.5224.72F1,43 = 0.020F1,43 = 0.635F1,43 = 1.250
ColourOLS6.2347.12   F1,42 = 2.514F1,42 = 0.009F1,42 = 3.592F1,42 = 0.061
PGLS7.8620.86   F1,42 = 3.720F1,42 = 0.016F1,42 = 2.423F1,42 = 0.700
Figure 2.

 Association between fruit colour parameters and chemical composition. The grey symbols represent the arithmetic average of fruits falling below the 10th quantile and above the 90th quantile, to illustrate the mean difference in chemical composition between fruits in the extremes of the colour distribution. Raw values are plotted, even though statistical analyses were performed with transformed data to meet the criterion of normality (results are listed in Tables 2 and 3).

Conversely, the best model explaining the variation in lipid fruit content across species included morphological traits but not colour. However, none of these variables was statistically significant in this model (Table 3). These results suggest that interspecific variation in lipid composition cannot be directly assessed from morphological traits or differences in fruit colour.

Comparisons between OLS and PGLS results suggest that inclusion of phylogenetic information improved the models (i.e. resulted in lower AICc values) for regressions with lipid and protein content as dependent variables but not for sugar and phenol concentration (Table 3). These results are qualitatively similar to those obtained from randomization analyses, which suggested that phylogenetic signal is significant for lipid and protein, but not for sugar and phenol, concentrations (Table 1).

Our statistical approach incorporating phylogenetic information shows that fruit chroma and fruit brightness can reveal reliable information on the sugar and protein contents of fleshy fruits, respectively. Thus, seed dispersers may be able to evaluate sugar content and possibly also protein content based upon the total brightness and chroma of fruit colours. This covariation among visual and chemical plant traits may reflect the outcome of natural selection favouring particular combinations of traits over others. This explanation is particularly likely because phylogenetic relationships appear as an important constraint for morphological fruit traits but not for colour traits. In contrast to the covariation between colour and nutritional traits, interspecific variation in any chemical content cannot be directly assessed from morphological traits. To a large extent, morphological traits show independent patterns of covariation relative to nutritional traits. This result supports the finding by Jordano (1995) and by Valido, Schaefer & Jordano (2011) who also found a marked decoupling of fruit morphology and fruit nutrients.

Phylogenetic signal in fruit characteristics

We observed significant phylogenetic signal in most morphological and nutritional traits, except for pulp fresh mass, carbohydrates and phenols. Significant signal was expected because morphological traits tend to be more conserved across the phylogeny, and error is generally low in morphological measurements. Even though the probability of detecting a signal depends on the number of species and on the K values, Blomberg, Garland & Ives (2003) found that 90% of the evaluated traits with sample sizes >20 showed statistically significant phylogenetic signal. Conversely, none of the parameters describing fruit colour showed significant signal. Although this may reflect a decrease in statistical power due to a lower sample size or intra-individual variation (e.g. in ripeness and thus colour), it is also possible that fruit colour is a strong target of selection and consequently more evolutionarily labile.

As a corollary, the lack of significant phylogenetic signal is per se not evident that fruit coloration is an adaptation to frugivores. It rather shows that phylogenetic constraints on fruit colours are weak compared to most other fruit traits as another broad interspecific comparison had shown previously (Voigt et al. 2004). Supporting fruit coloration as adaptation requires demonstrating that it evolved in response to established selection regimes by frugivores. Two recent studies suggested the importance of frugivores to fruit evolution finding that fruit colours differ among plant species dispersed by primates or bats and those dispersed by birds independently of phylogeny (Lomáscolo & Schaefer 2010; Lomáscolo et al. 2010).

The presence of significant phylogenetic signal in most traits illustrates the importance of incorporating phylogenetic information in statistical analyses. Models on protein and lipid that incorporated phylogenetic relationships (PGLS) yielded consequently higher Akaike weights than OLS models, while the reverse was true for sugars and phenols. This result indicates that the relationship between protein and brightness is evolutionary stable, while the relationship between chroma and sugar is evolutionary labile. These findings stress the importance of applying a phylogenetically based statistical method to document the distinct evolutionary history of trait associations.

Visual cues and fruit composition

Our study shows that chroma and to some extent fruit brightness can be indicative of sugar and protein contents, respectively. It needs to be noted, however, that the relationship between fruit brightness and proteins in pairwise correlation analyses was marginally significant at best, and that the possibility that fruit brightness indicates protein content should be therefore be interpreted cautiously and investigated in the future. This is particularly important because the relative importance of fruit brightness for detection under natural conditions is poorly known. In particular, a background of vegetation usually varies 3000-fold in brightness (Sumner & Mollon 2000), and this natural variation may make it more difficult for fruit consumers to detect fruit targets using brightness only.

High sugar contents in fruits are indicated by low chroma. We suggest that this relationship is best understood by considering the underlying biochemical mechanisms. Fruits with low chroma values are mainly achromatic, being predominantly black or purple black in our sample. These colours are imparted by high concentrations of anthocyanins, the predominant fruit pigments that often override the coloration imparted by other pigments such as carotenoids (Schaefer, McGraw & Catoni 2008). Importantly, sugars strongly up-regulate the anthocyanin biosynthetic pathway (Solfanelli et al. 2006) because the gene expression of key enzymes of that pathway, such as chalcone synthase, is directly induced by sugars (Takeuchi, Matsumoto & Hayatsu 1994). As such, the correlation between high sugar content and high anthocyanin content in fruits (resulting in unsaturated colours) is likely to be explicable because carbohydrates directly induce anthocyanin biosynthesis. If this conjecture is correct, we expect the negative correlation between chroma and sugar content in fruits to hold more widely across distinct vegetation communities. In this scenario, the covariance between chroma and sugar content is explicable by biochemistry and does not necessarily represent a signal that evolved this covariance to communicate.

In general, traits that indicate content will be especially effective in stimulating fruit removal if they signal rare compounds. Although our study showed that fruit brightness is not strongly correlated with protein content, it might be advantageous for plants to indicate high protein content as this is generally limited in fruits (Herrera 1987). A large proportion of fruits with high brightness values were orange or yellow in our study, corroborating the relationship between protein content and these fruit colours that Schaefer & Schmidt (2004) found in a Venezuelan rainforest. This is particularly noteworthy because Endler (1993) suggested that in the prevailing ambient light within forests yellow and yellow–green fruits maximize brightness.

Is the reliability of fruit colours in indicating fruit nutrients adaptive? In general, because multiple perceivers can react to fruit coloration, the design of a signal should present a trade-off between conspicuousness to intended perceivers such as seed dispersers and relative inconspicuousness to unintended perceivers such as visually oriented fruit and seed predators (see Endler 2000). According to the hypothesis of adaptive plant communication, we could thus predict that visually oriented fruit and seed predators should respond more weakly to variation in sugar content than to variation in contents that are not signalled (e.g. lipids). If this prediction is not supported, by-product information may seem a more plausible scenario. The hypothesis on by-product information predicts that information arises if it is not selected for by animals that perceive plant traits. For example, information could evolve as by-product of pleiotropy, correlational selection or selection imposed by biotic agents such fungi (Schaefer & Ruxton 2011).

The current evidence in favour of the hypothesis of adaptive communication or by-product information is mixed. In contrast to the expectations of adaptive fruit communication, phenolic content is not indicated by fruit coloration even though phenols increase fruit longevity in our community by deterring fruit predators (Cazetta, Schaefer & Galetti 2008). This could be explicable because seed dispersers are likewise deterred by phenols in fruit pulp (Schaefer, Schmidt & Winkler 2003) or because many of the fruit predators such as fungi or microbes are not visually oriented. Similarly, both seed dispersers and seed predators preferentially consume lipid-rich fruits (Schaefer, Schmidt & Winkler 2003; Cazetta, Schaefer & Galetti 2008), but lipid content is not indicated by fruit coloration. We thus emphasise that the determination of the relative selective pressures of seed dispersers and fruit and seed predators on specific fruit compounds is necessary to distinguish between adaptive and nonadaptive scenarios of fruit communication.

In sum, we suggest that shared biochemistry is a likely mechanism inducing the covariance between colour (the stimulus) and nutritional quality (as the unseen quality). By-product information represents a simpler mechanism for the reliability of fruit colours than adaptation to signalling and should therefore serve as a null hypothesis in plant–animal communication. Even though the information represented by fruit colours may not have evolved to inform seed dispersers on nutritional contents, fruit colours might still evolve as signals that enhance the detectability of fruit crops and might thereby ultimately increase plant fitness. Likewise, it remains to be tested whether plants can increase their reproductive success by transmitting informative signals. Finally, the concept of adaptive fruit communication should be tested rigorously against by-product information.

We thank Cláudio Bernardo and Vanessa G. Staggemeier for help with field work, Dr. José Roberto Trigo for laboratory facilities and help with chemical analyses. This work received financial support from FAPESP (Proc. 05/52726-9). E.C. thanks FAPESP (Proc. 03/08447-2) and M.G. receives a fellowship from CNPq. E.C. and H.M.S. received a DAAD fellowship during this project. E.L.R. is a Ramón y Cajal fellow supported by the MICINN (Spain).


• transboundary animal diseases;
  • emerging animal diseases;
  • prevention;
  • control;
  • early warning

Abstract: Transboundary animal diseases pose a serious risk to the world animal agriculture and food security and jeopardize international trade. The world has been facing devastating economic losses from major outbreaks of transboundary animal diseases (TADs) such as foot-and-mouth disease, classical swine fever, rinderpest, peste des petits ruminants (PPR), and Rift Valley fever. Lately the highly pathogenic avian influenza (HPAI) due to H5N1 virus, has become an international crisis as all regions around the world can be considered at risk. In the past decades, public health authorities within industrialized countries have been faced with an increasing number of food safety issues. The situation is equally serious in developing countries. The globalization of food (and feed) trade, facilitated by the liberalization of world trade, while offering many benefits and opportunities, also represents new risks. The GF-TADs Global Secretariat has carried out several regional consultations for the identification of priority diseases and best ways for their administration, prevention and control. In the questionnaires carried out and through the consultative process, it was noted that globally, FMD was ranked as the first and foremost priority. Rift Valley fever, and today highly pathogenic avian influenza, are defined as major animal diseases which also affect human health. PPR and CBPP, a disease which is particularly serious in Africa and finally, African swine fever (ASF) and classical swine fever (CSF) are also regionally recognised as top priorities on which the Framework is determined to work. The FAO philosophy—shared by the OIE—embraces the need to prevent and control TADs and emerging diseases at their source, which is most of the time in developing countries. Regional and international approaches have to be followed, and the FAO and OIE GF-TADs initiative provides the appropriate concepts and objectives as well as an organizational framework to link international and regional organizations at the service of their countries to better prevent and control the risks on animal and human health and the economic impact of TADs and emerging animal diseases.


Danaher Industrial Controls Group

Danaher Industrial Controls Group (DICG) introduces the + Series family of industrial controllers. Several new features include an easy-to-use programming interface and a “plug and play” options format designed to reduce customer inventories. The + Series reduces the installed cost of DIN temperature controllers. The product gives engineers more flexible control of processes by providing dual set points that can be selected from a remote location. Normally considered a high-end feature, remote setpoint capability is not usually found in value-priced, smaller-sized controllers.
Product Type:


Need a (social media) Miracle?

A few weeks back Virginia Miracle, our new EVP of Customer Success, and I sat down over coffee to debate social, brands, evolution, software and the future.  Most of our conclusions are super top secret and the world isn"™t ready to hear them, but here are a few thoughts from that meeting.

- The social web is real and not going anywhere"¦check.

- Consumers and business customers are being influenced by the social web"¦check.

- As a brand, it"™s daunting to integrate these social realities into the business"¦check.

- Lot"™s of companies are trying to add value between the big brands and the social web"¦check.

The world between the brands and the social web is evolving and growing up.  How is this world evolving?

What the heck are people saying about my brand on social?  That was the first question asked a few years ago.  Radian 6 showed up to help answer that question.

I"™ve just hired a social media intern (complete with a hoodie), how can they keep up with a couple social accounts?  Hootsuite and Tweetdeck showed up to help answer that question.

Holy cow I need a Facebook page(s) now.  Along came Buddy Media and Vitrue to do a little creative and write some HTML.

Now what?  What are the next questions we are hearing from big brands?

- How do I manage social strategically?

- How do I coordinate the work of 100"™s of employees and partners around the world?

- How do I manage 500 social accounts?

- How do I enable my people to be social"¦while having some order in the chaos?

- How can I use paid options like Facebook ads to amplify brand content for increased engagement?

- How can I have social media rules and policies while not seeming to have rules and policies?

- How can I see if it"™s all working and helping my business?

This is a hard problem. This isn"™t building a socially-enabled web page. It can"™t be approached with a simple consumer tool. This requires depth and breadth in social and software.  This is Spredfast.  We believe, when the dust settles, brands will run their social business on Spredfast.

Of course we"™d like to think software solves 100% of the problem"¦but we know that"™s not the case.  It"™s a combination of great technology and "know-how" combined for success.

Virginia and her "know how" team at Spredfast are here to help our customers make social part of their everyday business.  As for the rest of the company"¦well, we are all here to help Virginia by providing a social media management system that enables brands to organize and scale their social media initiatives.

Need a Miracle?

Rod Favaron's picture

Rod Favaron

Rod has served as President and CEO of Spredfast for the past five years, leading overall company operations and long-term strategic direction alike. Under Rod’s direction, the Spredfast team of over 500 employees helps more than 650 of the world’s largest brands connect to the people they care about most.


Joshua Bledsoe Named COO of the National FFA

Melissa Sandfort

Joshua Bledsoe was named chief operating officer of the National FFA Organization. Bledsoe will manage major FFA operations and lead the overall execution of the 557,318-member organization’s strategic plan, reporting directly to CEO Dr. Dwight Armstrong.

As COO, Bledsoe will lead key FFA organizational units, including education; convention and events management; partner services; information technology; marketing, communications and brand management; and merchandising and customer fulfillment.

As the North Carolina State Agricultural Education Leader, Bledsoe provided leadership and overall coordination for agricultural education within the state. He was charged with leading an 11-member state agricultural education team and ensuring professional development opportunities for teachers. Bledsoe also developed and maintained close working relationships with local, state and national agencies and organizations. A graduate of North Carolina State University, Bledsoe earned both undergraduate and master’s degrees in agricultural education.

Bledsoe will relocate to Indianapolis with his family to begin the new role on Feb. 18.

FFA, Youth


70th Annual Holocaust Observance Ceremony Held In Skokie A ceremony remembering the six million Jews murdered by the Nazis in World War II was held in Skokie Sunday.
130 Immigrants Take Citizenship Oath In ChicagoMore than 130 people - from 47 countries - became new citizens this afternoon in downtown Chicago.
Holocaust Survivors Remember Lives LostHolocaust survivors and their families gathered this past weekend in Skokie, remembering the 6 million people who died at the hands of the Nazis.

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electron diffraction, bending interference effects owing to the wavelike nature of a beam of electrons when passing near matter or through spacings in its submicroscopic structure that are comparable in size to the wavelength of an electron. According to the proposal (1924) of the French physicist Louis de Broglie, electrons and other particles have wavelengths that are inversely proportional to their momentum. Consequently, high-speed electrons have short wavelengths, a range of which are comparable to the spacings between atomic layers in crystals. A beam of such high-speed electrons should undergo diffraction, a characteristic wave effect, when directed through thin sheets of material or when reflected from the faces of crystals. Electron diffraction, in fact, was observed (1927) by C.J. Davisson and L.H. Germer in New York and by G.P. Thomson in Aberdeen, Scot. , and the wave The wavelike nature of electron beams was thereby experimentally established, thus supporting an underlying principle of quantum mechanics.

As an analytic method, electron diffraction is used to identify a substance chemically or to locate the position of atoms in a substance. This information can be read from the patterns that are formed when various portions of the diffracted electron beam cross each other and by interference make a regular arrangement of impact positions, some where many electrons reach and some where few or no electrons reach. Recorded photographically or otherwise, such a distribution is called a diffraction pattern, which when properly interpreted yields information about the nature and structure of the gas, liquid, or solid that caused the electron diffractionSome advanced analytical techniques, such as LEEDX (low-energy electron diffraction), depend on these diffraction patterns to examine solids, liquids, and gases.


Dr. Ray Pritchard Christian Blog and Commentary

Clinging to God Through Our Tears

Last weekend a young man died in a car accident, leaving his friends heartbroken and confused. I was asked to write to one of those friends to offer whatever encouragement I could. I was glad to do it, and as I did so I thought about how often I have done that over the years. Years ago I struggled with what to say in a situation of sudden death. Looking back, I think I felt the burden of trying to explain what happened so that the faith of those left behind will not be shattered. But that burden is far too heavy for me. Who am I to explain anything like that? I don't know why things happen the way that they do. I suppose that difference now is that I don't feel embarrassed saying that I don't know. And I've found it doesn't bother people when I tell the truth about my inability to explain the great mysteries of life and death. A few months ago a dear friend died in circumstances that were hard to accept. I do not know why things happened the way that they did. When we moved to Tupelo in October, it was deer-hunting season. A man in his forties came by to say that he would be hunting on my brother's property. He was pleasant, friendly, handsome, and he exuded that sort of casual self-confidence that makes you feel at ease in his presence. Later he shot a deer on our property and gave us some of the meat. Once or twice more he came around and we chatted briefly. A few weeks ago his teenage son and a friend were driving late at night on one of the many country roads near Tupelo. They were going over one hundred miles per hour, killing both young men instantly.

It doesn't seem to matter where you live. Playwright Noel Coward called this a "death-sentenced generation." Few things in life are more difficult than the sudden death of friend. And when it happens by some sort of accident, the mind wrestles with so many unanswerable questions, chief among them why. Why did things happen they way they did, and when they did? And why should a young man just starting out have his life so quickly cut short?

I have learned that where you start makes all the difference in thinking about sickness, suffering and death. If you start with the accident or with the sickness or with the death itself, you will never come to the right answer. I know many people whose faith has been badly shaken and even destroyed by the tragedies of life. I know that feeling myself. But I have learned that if you start at the tragedy and try to reason your way back to God, you won’t make it. You’ll fall off the ladder somewhere. None of us is smart enough to reason from a tragedy back to God. The only hope is to start at the other end, with what we know to be true about God. If you start with God, and who he is and why he sent his Son to the earth, and his wisdom, power, goodness and love, if you start there, you can slowly make your way back to the tragedy itself. I have walked that road myself many times. It’s not that this is some sort of magic trick that will make the pain go away (it won’t) or that will answer all your questions (it won’t do that either), but starting with God provides the only possible framework for answering the questions we all have.

Here are two Scriptures to meditate on. The first comes from Isaiah 53:10 in the New American Standard Bible: “But the LORD was pleased to crush Him, putting Him to grief.” Isaiah is speaking of the Father’s decision to put his Son to death on the cross for the sins of the world. Think about what that says. Not just that the Father sent his Son to die or that he allowed his Son to die. It is much stronger than that. In ways that we cannot fathom, it pleased the Lord to allow his Son to suffer and die. How can any father be pleased to crush his own son? I cannot imagine it. Parents do all they can to protect their children. But our Father was pleased (for the sake of our salvation) to crush his own Son. That tells us that God’s ways and our ways are not the same and we cannot judge him by human standards. The second verse is Psalm 115:3, “Our God is the heavens. He does whatever he pleases.” This means that God does what he wants and no one can stop him. We can say that another way. Here we come up against the bedrock of God himself. He is great and powerful beyond our imagining. All that he does is right, even those things we do not understand.

In the end we are left with God. It comes down to who God is and what we believe about him. We need an almighty God and we have one. We need a God of multiplied grace and we have one. It’s all about God. It’s not about us. Finally we turn to God because truly we have nowhere else to God. We cling desperately to God’s sovereignty and to his grace and we say to ourselves through our tears, We won’t stop now. We won’t give up. We will keep believing. We’ve come to far too turn back now.


Massachusetts Medical Society's Physician Focus

Infectious Disease: Fear vs. Evidence
Infectious diseases have plagued humans since the beginning of time, and the arrival of a new contagion brings uncertainty, confusion, and a race for a vaccine. The experiences of SARS in 2003, of H1N1 bird flu in 2009, Ebola in 2014, and now the Zika virus in 2016 are the most recent examples of threats targeting the public’s health. Groups such as the World Health Organization and U.S. Centers for Disease Control go on high alert for these threats. The media are quick to label them “epidemics” and “pandemics,” raising fears on the part of the public. Has media overreaction become the norm for these outbreaks? What roles do such agencies as the U.S. Centers for Disease Control play on the international stage in addressing these outbreaks. And just how should the public react?

Colon Cancer
Colorectal cancer is the second leading cause of cancer-related deaths in the U.S., after lung cancer. The disease affects both men and women, and is most often found in people 50 years of age and older. Screening for this disease saves lives, but one in three adults – some 23 million people – between 50 and 75 -- is not getting tested as recommended. What are the causes of colon cancer? How is the disease treated? Why do so many avoid testing? And what are the best screening tests?

Crisis in the Commonwealth: The Epidemic of Opioid Abuse
The epidemic of opioid and prescription drug abuse and misuse continues to affect individuals and families across the Commonwealth, regardless of location, economic status, or age. In 2014, the state saw 1,089 confirmed cases of fatal opioid overdoses, a 63 percent increase over 2012 and a 20 percent jump over 2013. In the last five years, nearly 3,800 have died from overdoses, and in the last ten years, more than 6,700. This edition of Physician Focus will examine the factors that lead to opioid abuse, the effects the epidemic is having on residents of Massachusetts, what is currently being done - and what additional efforts might be undertaken - to curb the abuse.

Common Skin Disorders
Skin is the largest organ in the human body, and it can be subjected to multiple disorders. Conditions such as acne, eczema, impetigo, psoriasis, rosacea, and melanoma affect millions of people. What are the most common skin disorders? What causes such conditions? What preventive steps can patients take to avoid these conditions? And how dangerous are they to overall health?

Concussion has become a priority focus in healthcare, with particular attention to the world of sports, from the professional level down to the youngest of players. The severity and long-term health effects of concussions have been recognized by coaches, parents, players and fans at all levels. This Physician Focus program will examine aspects of concussions, their causes and health consequences, and what is being done by public officials, schools, and other groups to prevent and reduce their incidence, including new laws and regulations by states to protect players in school-based activities.

Mindfulness and the Mind-Body Connection
In recent years, research into mind-body medicine has shown that psychological factors, such as our mental, emotional, and social states, can affect our physical health. Proponents of mind-body medicine say the practice of mindfulness can help improve health and be useful in managing illnesses chronic illnesses such as heart disease or arthritis. How do psychological factors affect our physical health? Just what is mindfulness and the mind-body connection? And how can using this approach improve our overall health?

Women and Heart Disease
Heart disease is the leading cause of death in the U.S., accounting for nearly 600,000 deaths a year, with more than half of the deaths occurring in men. Yet cardiovascular disease – heart disease, stroke, and high blood pressure – is the number one cause of death in American women, claiming more women’s lives than all cancers combined. Why are women more threatened by heart disease than other illnesses? What are the gender differences that play a role in this condition? Are there differences among racial or ethnic groups? What is hindering preventive efforts? And what can be done to reduce the threat?

Hearing Loss
Hearing loss is one of the most common chronic conditions Americans of all ages, with more than 30 million Americans age 12 and older having some level of impaired hearing, according to The National Institute on Deafness. What are the major causes of hearing loss? Who is most affected? What effect, if any, does hearing loss have on our overall health? What steps should we take to prevent hearing loss? And what remedies are available for those who lose all or part of their hearing?

Children’s Health: The Major Problems
The problems children face growing up today, as viewed through the eyes of their parents and other adults, are vastly different than those from just a few years ago. The C.S. Mott Children’s Hospital of the University of Michigan Health System has conducted an annual national poll on children’s health, rating adult perceptions of “big problems” in children’s health. What do adults see as the “big problems” in children’s health? Do they vary among different racial and ethnic groups? Are they different from those that pediatricians see as major issues? And how do pediatricians counsel their patients and their parents on the biggest threats to a child’s health?

Breast Cancer

Common Eye Disorders

Guns and Public Health

The Other Side of Alzheimer’s: Caregivers and Families
Dementia describes a group of cognitive disorders primarily affecting older adults and is usually marked by difficulty with language, motor activity, and the ability to plan and organize. The most well-know of these conditions is Alzheimer’s disease, currently affecting 5.3 million Americans. The number of patients with Alzheimer’s, however, is increasing rapidly along with an aging population, and estimates are that by 2050, up to 16 million people will be afflicted. The impact of this condition on a patient is slow and tragic. Yet the effects of dementia go far beyond the patient. What should families consider when confronted with a diagnosis of Alzheimer’s? What difficulties will patients and families face? And what resources are available to help them?

Diabetes: Persistent Epidemic
Diabetes is one of the country’s most prevalent chronic conditions, affecting nearly 29 million Americans. The disease is now the 7th leading cause of death in the U.S. and contributes to a variety of other conditions such as heart disease, blindness, and kidney disease. Why and how has this chronic condition become so prevalent? What steps should be taken to reduce this epidemic? What are the latest treatments available for patients? And are we close to a cure?

The Causes of Cancer
Cancer is the second leading cause of death in the U.S. after heart disease. Recent reports have indicated that most cancer types are just the result of “bad luck,” or chance mutations of cells. Other reports and research indicate that lifestyle choices, genetics, and the environment play important roles. How does cancer occur? Are the causes different for different types of cancer? What are the known risk factors? Can the disease be prevented? How much does the American public really know about cancer?

The Measles Outbreak and The Value of Vaccines
The current measles outbreak, in large part due to unvaccinated individuals, has prompted renewed concern by physicians and public health officials over vaccines and immunization. How and why are these diseases making a comeback? Why are patients and their parents avoiding vaccines in the face of scientific evidence of their preventive value? What are the risks of vaccination? What are the risks of not getting immunized? And what can physicians do to reinforce the importance of vaccines for both children and adults, called one of the ten greatest public health achievements of the 20th century?

Prescription Drug Abuse: The Physician’s Perspective
Abuse of opioids and prescription drugs has become a national public health problem in the United States. Many efforts – legislation, regulations, restrictions, prescription monitoring programs – have been undertaken by government officials, law enforcement, and health providers at all levels to reduce the problem – with varying results. At the same time, many patients are experiencing chronic pain, and patients and providers alike are concerned that overreaction will deprive patients of needed medications. What is the physician’s perspective of prescription drug abuse? What do those who treat the patients and write the prescriptions think should be done to reduce the problem? What are the responsibilities of physicians when prescribing and patients when using opioids?

Chronic Kidney Disease

Food and Your Health

Managing Your Chronic Disease

HPV: Human Papillomavirus

Is Marijuana Medicine?

End-of-Life Care: Advance Care Planning
Physicians are trained to promote wellness, cure illness, and preserve and protect life. Yet, death is inevitable, and health care providers are now paying more attention to end-of-life issues. One of the most important aspects of end-of-life issues is preparing advance directives. These include such items as a living will, health care proxy, durable power of attorney. Why should people prepare advance directives? What do they signify? How difficult are they to prepare? And how do they benefit the patient, family members, and health care providers?

Boards of Health: Public Health at the Local Level
They’re invisible to many citizens, but the work of the local boards of health in communities across the state is critical to our collective well-being and safety. This edition of Physician Focus will take an in-depth look at public health efforts at the local level by examining how local boards of health operate. What are the responsibilities of these boards? What kinds of power do they have? How, exactly, do they operate? Who are the people who watch out for our health and safety? And how do they interact with state public health officials?

Common and Emerging Infectious Diseases
The familiar ones are with us each year – West Nile virus, Easter Equine Encephalitis, Lyme disease. But outside of the U.S., unfamiliar infectious diseases like Chagus disease, dengue, Ebola, and Chikungunya virus – continue to affect millions around the world. And some are getting closer to the United States. How dangerous are these diseases? What are the biggest threats of infectious disease facing the U.S.? And how are public health officials acting to safeguard against them?

Oral Health
The U.S. Surgeon General’s first-ever report on oral health in America, issued in 2000, declared that oral diseases remain prevalent across the country, and that, for some populations, the lack of oral health was a “silent epidemic.” Evidence has shown that oral health and physical health are linked, and that oral complications are associated with respiratory disease, cardiovascular disease, and diabetes. How far have we progressed since the Surgeon General’s report? What are the factors contributing to a lack of oral health? How do we improve people’s oral health? And how can physicians and dentists work together on behalf of the patient?

Unequal Treatment: Disparities in Health Care
A dozen years ago, the Institute of Medicine issued its report, Unequal Treatment: Confronting Racial and Ethnic Disparities in Health Care, pointing out that racial and ethnic minorities receive poorer quality care than white patients. What’s causing this unequal treatment? What can physicians and patients do to improve their care? And how much progress have we made since the IOM’s landmark report?

In 1981, the Centers for Disease Control described a rare, then-unidentified lung disease affecting the immune system. It was the first official reporting of what would come to be known as human immunodeficiency virus, or HIV that leads to AIDS. Today, about 50,000 people in the U.S. get infected each year with HIV, and many do not know they are infected, and some 15,000 people die each year from AIDS. Worldwide, the figures are even higher. How far have we come in more than thirty years in our fight against HIV and AIDS?

Crohn’s and Colitis Diseases
Crohn’s and colitis are chronic diseases of the intestines, each affecting as many as 700,000 people in the U.S. What are the causes of these conditions? Who is most affected? How does it affect health and quality of life? And what treatments are available for these diseases?

Smoking, Tobacco and Health
January 2014 marks the 50th anniversary of the first Surgeon General’s report on the dangers of smoking and tobacco. While much progress has been made in getting people to stop using tobacco, smoking remains the leading cause of preventable death in the U.S. As the nations’ physicians refocus on anti-tobacco efforts, it’s time to review the impact of tobacco is having on our health and what can be done to continue to reduce the rate of smoking among all ages.

Violence and Mental Illness
The killings in Aurora, Colorado and Newtown, Connecticut in 2012 and at the Washington Navy Yard in 2013 are the latest in a long list of mass shootings in the U.S. that have called attention to the link between mental illness and violence. In recent Gallup polls, nearly half of Americans – 48% - blame the mental health system “a great deal” for mass shootings. What exactly is the relationship between mental illness and violence? And what role, if any, might mental health professionals play in reducing violent acts?

Hepatitis is one of several diseases affecting the liver, the largest organ in the human body that aids in critical functions of the body. Nearly four and half million Americans are living with chronic hepatitis, and most are unaware they are affected. What causes this condition? What are its symptoms? How is it diagnosed and treated? Who may be susceptible? And if left untreated, what consequences may occur?

Inside the ER
The hospital emergency department has become a mainstay of American medical care. An estimated one of every five Americans visit the ER each year, for a total of nearly 130 million visits annually. With only 4 percent of the nation’s physicians, emergency departments manage more than 10 percent of outpatient hospital visits, handling a wide range of medical challenges, often under difficult circumstances. What are the decisions emergency physicians and nurses face when patients present themselves? What should patients consider when thinking about visiting an emergency department for medical care? What is the role of the emergency department in today’s health care system? And what challenges do they face?

The Physician-Patient Relationship
The physician-patient relationship is regarded as the foundation of good health care, but medicine is constantly evolving and changing, and so, too, does the physician-patient relationship. How has this relationship evolved over the years? What elements make up a good relationship today? Will the relationship change with the move to “medical homes” and accountable care organizations? What should patients think about when seeking a primary care provider?

Complicated Grief
The loss of a loved one affects each of us deeply and moves us to mourning and bereavement following their death. After a period, most people gain acceptance of their loss and move forward with their lives. Some, however, are affected by complicated grief, a clinically significant and potentially debilitating condition. What are the causes of this severe grief? Who is at risk? What are the symptoms? How can it affect one’s health? And what kind of help is available to those who experience this condition?

Weight-Loss Surgery: Myths and Realities
Weight loss surgery has been touted as one solution to the problem of obesity, and in some cases, it’s also been known to eliminate diabetes. It’s a complex undertaking, however, that involves a lifetime of commitment, discipline, and attention to detail. Who are the best candidates for these procedures? What steps does a patient need to take for success? What are the surgical options available and what are the differences between them? What results can a patient reasonably expect, and what are the risks?

Disaster Medicine
The bombing at the Boston Marathon is the latest example of the role medical professionals and first responders play in meeting unexpected events. Whether natural or man-made disasters, medical personnel seem always ready to react quickly, to save lives and care for those in harm’s way. What goes into preparing for such events? What kinds of training and resources are necessary? And what is the impact on physicians, nurses and other first responders?

Joint Replacements
The number of joint replacements is soaring in the U.S., as more than a million people year are getting total replacements, usually for their hip or knee. As baby boomers age with arthritis and other conditions but still wish to remain active, these operations are expected to continue to increase. Who are the best candidates for these replacements? How expensive are they and how long do they last? What should patients know, pre- and post-surgery, about these procedures? And how successful have they been?
Check-ups and Screenings
The value of regular medical check-ups and screenings has come into question, dividing the medical community and causing confusion among patients. Independent groups such as the U.S. Preventive Services Task Force and The Cochrane Library in Europe say there’s little evidence that check-ups and screenings reduce health risks and can even do harm. Some physicians disagree. What’s prompting this divide within the medical community? How should patients react to this information? And what advice should they follow?
Youth Violence and Child Abuse
Understanding Depression
Depression is a chronic mental illness that affects one in ten adults in America and is a leading cause of disability for individuals 15 to 44. Though women are much more likely to experience depression, the illness can reach anyone, regardless of social, ethnic, or economic status. What causes this mental illness? How is depression diagnosed? Is there a link between depression and other diseases? And what are the treatments to address this condition?
Doctor’s Rx: Healthy Eating
The medical conditions associated with obesity, such as diabetes, heart disease, high blood pressure, and osteoarthritis, are too costly and too common, and are brought on in large measure by the lifestyles we lead. How active we are, our use of substances such as tobacco and alcohol, and particularly the foods we eat – are major causes of obesity and overweight.


Tiny organisms ate vast majority of methane gas released during Gulf of Mexico oil spill, scientists say

A dramatic bloom of methane-eating bacteria in the deep waters of the Gulf of Mexico made quick work of the vast majority of the methane gas released during the BP Deepwater Horizon disaster last spring and summer, according to a new paper published online today by the journal Science.

methane_eating_microbes.jpgView full sizeScientists say methane-eating microbes such as these deltaproteobacteria made short work of the vast majority of methane released from the BP Deepwater Horizon disaster, based on measurements of microbes and oxygen levels in a wide swath of water surrounding the rig.

In addition to explaining the fate of the methane gas -- which by weight made up 30 percent of the oil and gas mixture that spewed from the BP Macondo well -- the scientists' findings could spell good news for those concerned that future releases of frozen methane could add to the greenhouse gases blamed for global warming.

Methane, a primary constiuent of natural gas, remains in the atmosphere for approximately 9-15 years and is more than 20 times more effective in trapping heat in the atmosphere than carbon dioxide over a 100-year period, according to the Environmental Protection Agency.

A huge reserve of frozen methane resides below the ocean floor and is thawed by warming ocean temperatures when it permeates the surface through natural seeps or during an accidental release, like the Deepwater Horizon disaster.

Based on federal government and independent estimates, between 7.3 billion and 10.1 billion cubic feet of methane gas were released between April 20 and July 15, when the Macondo well was capped. By the beginning of October, however, the scientists had gathered evidence showing that the vast majority of methane was gone.

john_kessler_water_samples.jpgView full sizeTexas A&M University chemical oceanographer John Kessler tests a water sample.

The findings came as a surprise to the scientists doing the research, said Texas A&M University chemical oceanographer John Kessler, one of the paper's lead authors.

That's because scientists have historically found that deepwater microorganisms have consumed methane rather slowly from natural fissures in the sea floor. Early measurements of methane and oxygen levels around the BP well -- taken in June at depths between 2,600 feet and 3,900 feet -- seemed to confirm this expectation.

"Based on the high concentrations that we were seeing in the waters in June, we predicted that (the methane) would most likely be a component of the spill that would persist in the deep waters of the Gulf for years," Kessler said.

But samples taken during three cruises in late August, September and early October found that the methane had disappeared.

"We had made measurements of methane on nearly 700 different samples and found that it was right back down to the ambient levels of methane in the Gulf of Mexico waters," he said.

The researchers then focused on two other factors to explain where the methane went, Kessler said, starting with the types of microorganisms found in the water where the methane was previously found.

water_column_samples_rosette.jpgView full sizeA CTD rosette is lowered into the water to gather data and collect samples. CTD refers to information about the conductivity of the water, which indicates its saltiness; its temperature; and the depth, measured by pressure. The rosette is made up of water-collecting bottles that can be opened and closed at specified depths.

"The results that we had back in June showed a community structure that was dominated by oil-degrading organisms, and in that community structure, there were undetectable levels of methane-degrading organisms," he said. "Contrast that to what we were measuring in September, and there was a much more diminished population of oil-degrading organisms and a greater population of methane-degrading organisms than we'd seen anywhere around the planet."

To get an idea of how much methane those organisms had eaten, the scientists measured the oxygen content of the water.

"As we digest food, we consume oxygen, and when these microbes respire methane, they are going to consume oxygen as well," Kessler said. "If the methane had simply diluted, dispersed, traveled someplace that maybe we didn't look, we wouldn't see nearly as much loss of oxygen."

The researchers sampled 36,000 square miles covering the entire area where the methane deepwater plume had originally been found, he said. That included 207 monitoring stations where more than 1,000 oxygen measurements were made.

Kessler said that the lack of oxygen in the water supported the finding that microbes had consumed the gas.

The latest findings follow a study published in November by scientists with Alabama's Dauphin Island Sea Lab, in IOP Publishing's Environmental Research Letters, that found that microscopic animals found drifting in Gulf waters, called zooplankton, contained concentrations of carbon atoms that indicated they had feasted on the oil portion of the spill.

The new results are promising for those concerned about the potential for future natural methane releases, triggered by warming oceans, adding to greenhouse gases that are causing global warming, Kessler said.

"This really set up a natural laboratory, an experiment if you will, that we would never have been allowed to do as a test," he said. "The ocean sea floor is by far the largest global reservoir of methane. What our study shows is that this does not have the capacity to influence climate."

But Kessler warned that conclusion applies only to a similar-sized release in a similar ocean setting.

Three different kinds of settings might still result in methane reaching the atmosphere, he said:

Frozen methane released from sites in shallower water could reach the surface and the atmosphere before organisms have the time to eat it.

There may be areas where methane could be released from the sea floor where natural seeps have not created populations of organisms able to respond quickly.

And there may be releases that occur over years or centuries, as has happened in the geologic past, where the timing or the amount of methane released could overwhelm the natural defenses seen in the Deepwater Horizon incident.

Kessler said researchers also are studying the ultimate fate of the carbon broken down by the Gulf methane-eating organisms, including whether the carbon dioxide they create may have increased the acidity of Gulf waters.

In addition to Kessler, the research involved scientists from the University of California, Santa Barbara, and University of New Hampshire.

Mark Schleifstein can be reached at or 504.826.3327.


Chip Multiprocessors (CMPs) are flexible, high-frequency platforms on which to support Thread-Level Speculation (TLS). However, for TLS to deliver on its promise, CMPs must exploit multiple sources of speculative task-level parallelism, including any nesting levels of both subroutines and loop iterations. Unfortunately, these environments are hard to support in decentralized CMP hardware: since tasks are spawned out-of-order and unpredictably, maintaining key TLS basics such as task ordering and efficient resource allocation is challenging.

While the concept of out-of-order spawning is not new, this paper is the first to propose a set of microarchitectural mechanisms that, altogether, fundamentally enable fast TLS with out-of-order spawn in a CMP. Moreover, we develop a fully-automated TLS compiler for aggressive out-of-order spawn. With our mechanisms, a TLS CMP with four 4-issue cores achieves an average speedup of 1.30 for full SPECint 2000 applications; the corresponding speedup for in-orderonly spawn is 1.04. Overall, our mechanisms unlock the potential of TLS for the toughest applications.


Booklet 'Facts about Commonwealth Hostels Limited' published by Commonwealth Hostels Ltd, 1967. The booklet has information about: the company's role in Australian the migrant hostels, the various the facilities and services provided by them, information about the hostel reconstruction programme, which began in 1965, and a description of the guest houses and non-migrant hostels also operated by the company. The list on the last page of the booklet indicates that in 1967 there were 28 migrant hostels and 20 guest houses and non-migrant hostels managed by Commonwealth Hostels Ltd.

Commonwealth Hostels Limited was created in 1951 to operate and manage Commonwealth migrant hostels. In 1978 the company changed its name to Commonwealth Accommodation and Catering Services (CACS), which reflected its role in catering and accommodation within a range of non-migrant government facilities as well.

Physical Description

Six page booklet with a black and white photo of the Gowrie guest-house in the ACT on the cover.

Statement of Significance/ Technical significance:
The stories of migrants and the organizations that assisted them comprise a significant part of Australian post-war history. Since World War II, thousands of government-assisted migrants and refugees have experienced arrival and accommodation at the migrant hostels. Yet migrant hostels are an under-documented area of Australia's immigration history - with the exception of Bonegilla Migrant Reception Centre, which was managed by the Department of Immigration. This collection is significant as it contributes to filling the gap in knowledge about the Commonwealth migrant hostels, which were a function of the Department of Labour and National Service. This collection and the accompanying archival documents are a rare find. Items from the migrant hostels were often sold or disposed of by the government soon after they were closed-down. Many migrants have kept photos taken during their stay at the hostels but day-to-day items belonged to the Company and were returned to the hostel upon departure. This collection has the potential enhance collections in cultural institutions such the NSW Powerhouse Museum and Migration Heritage Centre (Villawood [Westbridge] and Cabramatta hostels).

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Results for: 1215

Why are the years 1066 and 1215 important to English history?

In the year 1066 William the Conqueror invaded Britain, won the battle of Hastings defeating Harold Godwinson and on Christmas day of the same year he was crowned King of Engl (MORE)

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What century was 1215 in?

To get the century, just use the next number up. So the  12-hundreds would be the 13th century.
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What document was signed by King John of England in 1215?

it was called the magna carta and the barons forced him to sign it because he was evil The Magna Carta, or Great Charter, in English.
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What was the document signed by King John in 1215 that granted englishmen basic human rights?

King John of England was forced to sign the Magna Carta at Runnymede on 15 June 1215. The Magna Carta, also called Magna Carta Libertatum, required that the King proclaim cert (MORE)


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The Tennis Anti-Doping Programme is a comprehensive and internationally-recognised programme that applies to all players who hold an ATP or WTA ranking, or who enter or compete in events organised, sanctioned or recognised by the ITF.

This includes Grand Slam tournaments, Davis Cup and Fed Cup ties, Olympic and Paralympic Tennis Events, ATP and WTA tournaments, ATP Challenger Tour tournaments, ITF Pro Circuit tournaments, ITF Junior events, ITF Seniors events, ITF Wheelchair events and ITF Beach Tennis Tour events.

-Maintain the integrity of tennis

-Protect the health and rights of all tennis players.

In 2011, the Programme conducted over 2,000 doping control tests, both in-competition and out-of-competition, and including both urine and blood samples.

If you have any general questions about the Tennis Anti-Doping Programme, please email the following address:

Enquiries relating to any particular substances, medications and/or Therapeutic Use Exemptions should be addressed to International Doping Tests and Management (IDTM):

Phone: +46 8 555 10 999
Fax: + 46 8 555 10 995


Category: Cryptozoology

Cryptozoology is the study of animals that haven’t been proven to exist. In Greek, it quite literally means “the study of hidden animals”. Creatures (or cryptids) can often be broken into one of 3 groups: prehistoric or extinct creatures (dinosaurs, etc), mythical creatures such as Bigfoot or Nessie and finally mutated or very different versions of common creatures (such as phantom cats, etc). While Cryptozoology isn’t recognized as an official branch of Zoology, many creatures once thought to be cryptids have actually been proven to exist. A few examples are:

* Okapi
* the Mountain Gorilla
* the Giant Squid

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Cryptozoology on the Upper Mississippi

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Gef the Talking Mongoose

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The Tale of The Chinese Wildman


Improving the Resilience of Transport Networks to Large-scale Failures

Telecommunication networks have to deal with fiber cuts, hardware malfunctioning and other failures on a daily basis, events which are usually treated as isolated and unrelated. Efficient methods have been developed for coping with such common failures and hence users rarely notice them. Although less frequently, there also arise cases of multiple failures with catastrophic consequences. Multiple failures can occur for many reasons, for example, natural disasters, epidemic outbreaks affecting software components, or intentional attacks. This paper investigates new methods for lessening the impact of such failures in terms of the number of connections affected.

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