Living things like orchids, hummingbirds, and the peacock's tail have abstract designs with a beauty of form, pattern and colour that artists struggle to match. The beauty that people perceive in nature has causes at different levels, notably in the mathematics that governs what patterns can physically form, and among living things in the effects of natural selection, that govern how patterns evolve. Mathematics seeks to discover and explain abstract patterns or regularities of all kinds. Visual patterns in nature find explanations in chaos theory, fractals, logarithmic spirals, topology and other mathematical patterns. For example, L-systems form convincing models of different patterns of tree growth.
Causes
Patterns in nature
Patterns in nature | Causes
Sorry. I cannot find the answer based on the context. Patterns from nature Yes, Patterns from nature (as art) "On Growth and Form"
what does patterns in nature refer to?
user
They are visible regularities of form found in the natural world.
assistant
what patterns does it include?
user
It includes symmetries, trees, spirals, meanders, waves, foams, tessellations, cracks and stripes.
assistant
what is it caused by?
user
Causes can be in the mathematics that governs what patterns can physically form, and among living things in the effects of natural selection, that govern how patterns evolve.
assistant
were these indicated in any books?
user
Living things like orchids, hummingbirds, and the peacock's tail have abstract designs with a beauty of form, pattern and colour that artists struggle to match. The beauty that people perceive in nature has causes at different levels, notably in the mathematics that governs what patterns can physically form, and among living things in the effects of natural selection, that govern how patterns evolve. Mathematics seeks to discover and explain abstract patterns or regularities of all kinds. Visual patterns in nature find explanations in chaos theory, fractals, logarithmic spirals, topology and other mathematical patterns. For example, L-systems form convincing models of different patterns of tree growth.
Patterns in nature | Causes
Natural patterns are sometimes formed by animals, as in the Mima mounds of the Northwestern United States and some other areas, which appear to be created over many years by the burrowing activities of pocket gophers, while the so-called fairy circles of Namibia appear to be created by the interaction of competing groups of sand termites, along with competition for water among the desert plants.
Patterns in nature | Pattern formation
Pioneering authors General books Patterns from nature (as art)
Patterns in nature | Bibliography
The young leopards and ladybirds, inheriting genes that somehow create spottedness, survive. But while these evolutionary and functional arguments explain why these animals need their patterns, they do not explain how the patterns are formed.
Patterns in nature | Spots, stripes
Scottish biologist D'Arcy Thompson pioneered the study of growth patterns in both plants and animals, showing that simple equations could explain spiral growth. In the 20th century, the British mathematician Alan Turing predicted mechanisms of morphogenesis which give rise to patterns of spots and stripes. The Hungarian biologist Aristid Lindenmayer and the French American mathematician Benoît Mandelbrot showed how the mathematics of fractals could create plant growth patterns. Mathematics, physics and chemistry can explain patterns in nature at different levels. Patterns in living things are explained by the biological processes of natural selection and sexual selection. Studies of pattern formation make use of computer models to simulate a wide range of patterns.
Patterns in nature | Introduction
The laws of physics apply the abstractions of mathematics to the real world, often as if it were perfect. For example, a crystal is perfect when it has no structural defects such as dislocations and is fully symmetric. Exact mathematical perfection can only approximate real objects. Visible patterns in nature are governed by physical laws; for example, meanders can be explained using fluid dynamics.
Patterns in nature | Causes
Darwinian evolution by natural selection is pervasive in literature, whether taken optimistically in terms of how humanity may evolve towards perfection, or pessimistically in terms of the dire consequences of the interaction of human nature and the struggle for survival. Among major responses is Samuel Butler's 1872 pessimistic "Erewhon" ("nowhere", written mostly backwards). In 1893 H. G. Wells imagined "The Man of the Year Million", transformed by natural selection into a being with a huge head and eyes, and shrunken body.
Natural selection | In fiction
Further, as Cuthill and Székely indicate, the bodies of animals that have such patterns must therefore have been shaped by natural selection.
Coincident disruptive coloration | Evidence for natural selection
Patterns in nature are visible regularities of form found in the natural world. These patterns recur in different contexts and can sometimes be modelled mathematically. Natural patterns include symmetries, trees, spirals, meanders, waves, foams, tessellations, cracks and stripes. Early Greek philosophers studied pattern, with Plato, Pythagoras and Empedocles attempting to explain order in nature. The modern understanding of visible patterns developed gradually over time. In the 19th century, the Belgian physicist Joseph Plateau examined soap films, leading him to formulate the concept of a minimal surface. The German biologist and artist Ernst Haeckel painted hundreds of marine organisms to emphasise their symmetry.
Patterns in nature | Introduction
Early Greek philosophers attempted to explain order in nature, anticipating modern concepts. Pythagoras (c. 570–c. 495 BC) explained patterns in nature like the harmonies of music as arising from number, which he took to be the basic constituent of existence. Empedocles (c. 494–c. 434 BC) to an extent anticipated Darwin's evolutionary explanation for the structures of organisms. Plato (c. 427–c. 347 BC) argued for the existence of natural universals. He considered these to consist of ideal forms ( "eidos": "form") of which physical objects are never more than imperfect copies. Thus, a flower may be roughly circular, but it is never a perfect circle.
Patterns in nature | History
Alan Turing, and later the mathematical biologist James Murray, described a mechanism that spontaneously creates spotted or striped patterns: a reaction–diffusion system. The cells of a young organism have genes that can be switched on by a chemical signal, a morphogen, resulting in the growth of a certain type of structure, say a darkly pigmented patch of skin. If the morphogen is present everywhere, the result is an even pigmentation, as in a black leopard. But if it is unevenly distributed, spots or stripes can result. Turing suggested that there could be feedback control of the production of the morphogen itself.
Patterns in nature | Pattern formation
In the wet season, mate selection returned to 1:1 proportions.
Anartia fatima | Genetics of color patterns
Nature provides examples of many kinds of pattern, including symmetries, trees and other structures with a fractal dimension, spirals, meanders, waves, foams, tilings, cracks and stripes.
Pattern | Nature
Great Darwinist Ronald Fisher worked out mathematical theorems to help answer this kind of questions. But, for Popper and others, there is no (falsifiable) law of Natural Selection in this, because it only applies to some rare traits. Instead, for Popper, the work of Fisher and others on Natural Selection is part of an important metaphysical research program.
Falsifiability | Natural selection
This pattern does not seem to follow any particular climatic rule and may be due to other environmental factors, such as predation and human encroachment.
Platypus | Description
Charles Darwin and Mr. Alfred Wallace.
On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection | The paper
More puzzling is the reason for the fivefold (pentaradiate) symmetry of the echinoderms. Early echinoderms were bilaterally symmetrical, as their larvae still are. Sumrall and Wray argue that the loss of the old symmetry had both developmental and ecological causes.
Patterns in nature | Symmetry
Apart from this nonlinearity, barchans behave rather like solitary waves.
Patterns in nature | Waves, dunes
From most random initial patterns of living cells on the grid, observers will find the population constantly changing as the generations tick by. The patterns that emerge from the simple rules may be considered a form of mathematical beauty. Small isolated subpatterns with no initial symmetry tend to become symmetrical. Once this happens, the symmetry may increase in richness, but it cannot be lost unless a nearby subpattern comes close enough to disturb it. In a very few cases, the society eventually dies out, with all living cells vanishing, though this may not happen for a great many generations. Most initial patterns eventually burn out, producing either stable figures or patterns that oscillate forever between two or more states; many also produce one or more gliders or spaceships that travel indefinitely away from the initial location.
Conway's Game of Life | Iteration
In Chapter III, Darwin asks how varieties "which I have called incipient species" become distinct species, and in answer introduces the key concept he calls "natural selection"; in the fifth edition he adds, "But the expression often used by Mr. Herbert Spencer, of the Survival of the Fittest, is more accurate, and is sometimes equally convenient." Owing to this struggle for life, any variation, however slight and from whatever cause proceeding, if it be in any degree profitable to an individual of any species, in its infinitely complex relations to other organic beings and to external nature, will tend to the preservation of that individual, and will generally be inherited by its offspring ...
On the Origin of Species | Struggle for existence, natural selection, and divergence
Cott's description and in particular his drawings convinced biologists that the markings, and hence the camouflage, must have survival value (rather than occurring by chance); and further, as Cuthill and Székely indicate, that the bodies of animals that have such patterns must indeed have been shaped by natural selection.
Coloration evidence for natural selection | Coincident disruptive coloration
Chapter IV details natural selection under the "infinitely complex and close-fitting ... mutual relations of all organic beings to each other and to their physical conditions of life". Darwin takes as an example a country where a change in conditions led to extinction of some species, immigration of others and, where suitable variations occurred, descendants of some species became adapted to new conditions. He remarks that the artificial selection practised by animal breeders frequently produced sharp divergence in character between breeds, and suggests that natural selection might do the same, saying:
On the Origin of Species | Struggle for existence, natural selection, and divergence
Bateson revisited the topic in his 1979 book "Mind and Nature: A Necessary Unity", and other scholars have continued to explore the connection between natural selection and systems theory.
On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection | As an influence on cybernetics
Influenced by deism, Hutton thought the mechanism allowed species to form varieties better adapted to particular conditions and provided evidence of benevolent design in nature. Studies of Charles Darwin's notebooks have shown that Darwin arrived separately at the idea of natural selection which he set out in his 1859 book "On the Origin of Species", but it has been speculated that he had some half-forgotten memory from his time as a student in Edinburgh of ideas of selection in nature as set out by Hutton, and by William Charles Wells and Patrick Matthew who had both been associated with the city before publishing their ideas on the topic early in the 19th century.
James Hutton | Evolution
Wolfram's claim that natural selection is not the fundamental cause of complexity in biology has led journalist Chris Lavers to state that Wolfram does not understand the theory of evolution.
A New Kind of Science | Natural selection
One explanation is that this allows trees to better withstand high winds. Simulations of biomechanical models agree with the rule.
Patterns in nature | Trees, fractals
On the voyage of the "Beagle" the young Charles Darwin took a break between graduating and starting his career as a clergyman to study the natural history of South America, an interest he had developed at the University of Edinburgh and the University of Cambridge. Influenced by Charles Lyell's "Principles of Geology", he became an able geologist as well as collecting plant and animal specimens, and fossils of gigantic extinct mammals. By the return journey, he was connecting patterns of geographical and historical distribution, and starting to doubt the stability of Species. In September 1838 he conceived his theory of natural selection as the cause of evolution, then as well as developing his career as a geologist and writer worked privately on finding evidence and answering possible objections.
On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection | Events leading up to the publication
Wallace noted that snow camouflage, especially plumage and pelage that changed with the seasons, suggested an obvious explanation as an adaptation for concealment. Poulton's 1890 book, "The Colours of Animals", written during Darwinism's lowest ebb, used all the forms of coloration to argue the case for natural selection. Cott described many kinds of camouflage, and in particular his drawings of coincident disruptive coloration in frogs convinced other biologists that these deceptive markings were products of natural selection. Kettlewell experimented on peppered moth evolution, showing that the species had adapted as pollution changed the environment; this provided compelling evidence of Darwinian evolution.
Coloration evidence for natural selection | Introduction
While there, he observed that almost all of the species in the park occupied large geographic ranges, and despite the heterogeneity of habitats across these ranges, individuals were mostly identical across locations, indicating that little local adaptation had taken place. He described the cyclical life history pattern he believed responsible for this pattern: a species begins as a small population occupying a small area with little genetic variation, but then over the course of a few generations grows to occupy a large area, either because of the emergence of a genotype successful over a wider range, or because of the removal of a geographic barrier.
Ecological fitting | Origin
The papers were published in ten parts over ten years in three different journals.
A Mathematical Theory of Natural and Artificial Selection | Overview
In later editions of "Origin", Darwin expanded the role attributed to the inheritance of acquired characteristics. Darwin also admitted ignorance of the source of inheritable variations, but speculated they might be produced by environmental factors. However, one thing was clear: whatever the exact nature and causes of new variations, Darwin knew from observation and experiment that breeders were able to select such variations and produce huge differences in many generations of selection. The "observation" that selection works in domestic animals is not destroyed by lack of "understanding" of the underlying hereditary mechanism. Breeding of animals and plants showed related varieties varying in similar ways, or tending to revert to an ancestral form, and similar patterns of variation in distinct species were explained by Darwin as demonstrating common descent.
On the Origin of Species | Variation and heredity
Another way the authors put the same point is as follows: If the mechanism of natural selection (as it is currently formulated) is correct, then it is a paradigm example of intensional causation. Intensional causation requires either (1) there be a mind involved in the causal process, or (2) the causal mechanism has access to nomological laws. Since there is neither (1) nor (2) at the biological level, the theory of natural selection cannot be correct.
What Darwin Got Wrong | The problem of "selection-for"
Existing patterns of biodiversity have been shaped by repeated formations of new species (speciation), changes within species (anagenesis) and loss of species (extinction) throughout the evolutionary history of life on Earth. Morphological and biochemical traits are more similar among species that share a more recent common ancestor, and can be used to reconstruct phylogenetic trees.
Evolution | Introduction
H. P. Madrell writes that "the proper but cumbersome way of describing change by evolutionary adaptation [may be] substituted by shorter overtly teleological statements" for the sake of saving space, but that this "should not be taken to imply that evolution proceeds by anything other than from mutations arising by chance, with those that impart an advantage being retained by natural selection." However, Lennox states that in evolution as conceived by Darwin, it is true both that evolution is the result of mutations arising by chance and that evolution is teleological in nature. Statements that a species does something "in order to" achieve survival are teleological.
Four causes | Biology
Charles Darwin and Alfred Russel Wallace's presentation of natural selection, coupled to the idea of evolution in Western thought, had gained acceptance due to the wealth of observational data provided and the seeming replacement of divine law with natural law in the affairs of men. However, the mechanism of natural selection described at the time only explained how organisms adapted to variation. The cause of genetic variation was unknown at the time. St. George Jackson Mivart's "On the Genesis of Species" (1872) and Edward Cope's "Origin of the Fittest" (1887) raised the need to address the origin of variation between members of a species.
Emergent evolution | Response to Darwin's "Origin of Species"
Darwin's aims were twofold: to show that species had not been separately created, and to show that natural selection had been the chief agent of change. He knew that his readers were already familiar with the concept of transmutation of species from "Vestiges", and his introduction ridicules that work as failing to provide a viable mechanism. Therefore, the first four chapters lay out his case that selection in nature, caused by the struggle for existence, is analogous to the selection of variations under domestication, and that the accumulation of adaptive variations provides a scientifically testable mechanism for evolutionary speciation. Later chapters provide evidence that evolution has occurred, supporting the idea of branching, adaptive evolution without directly proving that selection is the mechanism.
On the Origin of Species | Nature and structure of Darwin's argument
The sixth chapter discusses the evidence for natural selection from experiments in the laboratory and observations of nature. He considered examples of camouflage such as industrial melanism, in which moths and other arthropods evolve darker pigmentation when exposed to an environment with a lot of soot in it. He refuted some Mendelian misconceptions about the effectiveness of natural selection, but he also rejected the strict selectionism of Fisher.
Genetics and the Origin of Species | Selection
In the arena of "scope" he considers the relevance of natural selection to the larger scale patterns of life.
The Structure of Evolutionary Theory | Summary
Natural selection is often portrayed as a “mechanism”, or is personified as a causal agency... In reality, the differential “selection” of a trait, or an adaptation, is a consequence of the functional effects it produces in relation to the survival and reproductive success of a given organism in a given environment. It is these functional effects that are ultimately responsible for the trans-generational continuities and changes in nature.
Emergence | Emergence and evolution
Several philosophers of the classical era, including Empedocles and his intellectual successor, the Roman poet Lucretius, expressed the idea that nature produces a huge variety of creatures, randomly, and that only those creatures that manage to provide for themselves and reproduce successfully persist. Empedocles' idea that organisms arose entirely by the incidental workings of causes such as heat and cold was criticised by Aristotle in Book II of "Physics". He posited natural teleology in its place, and believed that form was achieved for a purpose, citing the regularity of heredity in species as proof. Nevertheless, he accepted in his biology that new types of animals, monstrosities (τερας), can occur in very rare instances ("Generation of Animals", Book IV).
Natural selection | Pre-Darwinian theories
Chaos theory predicts that while the laws of physics are deterministic, there are events and patterns in nature that never exactly repeat because extremely small differences in starting conditions can lead to widely differing outcomes.. The patterns in nature tend to be static due to dissipation on the emergence process, but when there is interplay between injection of energy and dissipation there can arise a complex dynamic. Many natural patterns are shaped by this complexity, including vortex streets, other effects of turbulent flow such as meanders in rivers. or nonlinear interaction of the system
Pattern | Chaos, turbulence, meanders and complexity
As species always breed beyond available resources, favourable variations would make organisms better at surviving and passing the variations on to their offspring, while unfavourable variations would be lost. He wrote that the "final cause of all this wedging, must be to sort out proper structure, & adapt it to changes", so that "One may say there is a force like a hundred thousand wedges trying force into every kind of adapted structure into the gaps of in the economy of nature, or rather forming gaps by thrusting out weaker ones." This would result in the formation of new species.
Charles Darwin | Malthus and natural selection
It contains the following chapters: The book also contains an extensive appendix containing the majority of Haldane's mathematical treatment of the subject.
The Causes of Evolution | Chapters
But, writes Yost, Beddard was not alone in being wary of natural selection.
Animal Coloration (book) | Darwinism
Natural design has attribution to the process of natural selection. All species have been designed based on their life situation in order to have more offspring. This resulted as only better designed organisms can be found today because natural selection is only limited by the rapidity of environment change and the capacity of the genes to generate variation. Moreover, the theory of evolution by natural selection can some how explain the behavior of animals.
Natural design | History
The book is divided into two parts. Part One is a review of "new facts and new non-selectional mechanisms that have been discovered in biology". Part Two is a discussion of "the logical and conceptual bases of the theory of natural selection". At the outset, the authors state their atheism and commitment to naturalistic explanations, and add that they accept evolution and common descent, but doubt that evolution proceeds by natural selection.
What Darwin Got Wrong | Summary
It's accessible to non-biologists and laymen, useful for teachers and undergrads, and ... researcher[s]." The evolutionary biologist Larry Flammer "warns" readers that when they look at the pictures or study Held's diagrams, they, "will be captivated by the full-page captions, and probably drawn into the effort to really understand what is happening. The graphics do, indeed, help immensely to do this." Flammer notes, too, that many of the, "nuts and bolts of evolution, deeper than just natural selection," are on display in the book, revealing, "precisely what genetic/physiological mechanisms are being selected for." The molecular biologist Arnaud Martin observes that, "As children, we have all wondered about 'the How and the Why' of animal features, and if you are reading this it is in fact quite possible that a similar inquisitiveness still burns within you.
How the Snake Lost Its Legs | Reception
The main themes of the third chapter are borrowed from Dawkins' own book, "The Blind Watchmaker". This chapter shows how the gradual, continuous and cumulative enhancement to organisms via natural selection is the only mechanism which can explain the complexity we observe all around us in nature. Dawkins adamantly refutes the ""I cannot believe so and so could have evolved by natural selection"" argument of Creationists, calling it the "Argument from Personal Incredulity". Creationists often claim that some features of organisms (e.g. resemblance of Ophrys (orchid) to female wasp, figure-eight dances of honeybees, mimicry of stick insects, etc.) are too complicated to be a result of evolution.
River Out of Eden | Do good by stealth
Eva Jablonka and Marion Lamb, for example, call themselves neolamarckists. Reviewing the evidence, David Haig observes that any such mechanisms must themselves have evolved through natural selection.
Jean-Baptiste Lamarck | Legacy
Natural selection, introduced in 1859 as the central mechanism of evolution by Charles Darwin, is the differential survival and reproduction of individuals due to differences in phenotype. The mechanism directly implies evolution, a change in heritable traits of a population over time.
Teleology in biology | Natural selection
The camouflage mechanism used by the species provided compelling evidence for evolution by natural selection. The zoologist Hugh Cott's drawings and description of the frog's "coincident disruptive coloration" showed that its pattern, forming bold stripes on the legs and body, lined up (coincided) exactly when the legs were tightly folded into the body at rest, effectively disrupting its outline. The zoologists I. C. Cuthill and A. Székely noted that the way the configuration works indicates that it must have survival value, implying natural selection at work.
Afrixalus fornasini | Evidence for natural selection
The proximate and ultimate causes for this pattern have been a subject of intense debate involving the development of ideas on group, individual, and gene-centric views of selection.
Avian clutch size | Introduction
A Quatzoli child is created in a forge and given a sliver of its parent's mind, which allows it to begin its life. As the child learns, its brain grows around the sliver until it is time to divide its mind for its own children. Because of this system, these beings are living books with accumulated knowledge passed down from their ancestors.
The Bookmaking Habits of Select Species | Quatzoli
Darwin's ideas were inspired by the observations that he had made on the second voyage of HMS "Beagle" (1831–1836), and by the work of a political economist, Thomas Robert Malthus, who, in "An Essay on the Principle of Population" (1798), noted that population (if unchecked) increases exponentially, whereas the food supply grows only arithmetically; thus, inevitable limitations of resources would have demographic implications, leading to a "struggle for existence". When Darwin read Malthus in 1838 he was already primed by his work as a naturalist to appreciate the "struggle for existence" in nature. It struck him that as population outgrew resources, "favourable variations would tend to be preserved, and unfavourable ones to be destroyed.
Natural selection | Darwin's theory
Ramsey's next argumentative manoeuvre is to point out that traits are not randomly scattered across potential life histories; there are patterns. “These patterns” he states “provide the basis for the notion of individual and human nature”. While one's ‘individual nature’ consists of the pattern of trait clusters distributed across that individual's set of possible life histories, Human Nature, Ramsey defines as “the pattern of trait clusters within the totality of extant human possible life histories”. Thus, if we were to combine all possible life histories of all individuals in existence we would have access to the trait distribution patterns that constitute human nature.
Human nature | "Life-history trait cluster" account (Ramsey)
He found that only the movement of an animal would cause the plants to react, and concluded that this was an evolutionary adaptation to conserve energy for prey and to ignore stimuli that were not likely to be nutritious. He also discovered that while some plants have distinct trap-like structures, others produce sticky fluids to ensnare their prey and concluded that this was an example of natural selection pressure resulting in various methods for food capture.
Insectivorous Plants (book) | Introduction
Darwin pointed out that by the theory of natural selection "innumerable transitional forms must have existed," and wondered "why do we not find them embedded in countless numbers in the crust of the earth." That clearly defined species actually do exist in nature in both space and time implies that some fundamental feature of natural selection operates to generate and maintain species.
Speciation | Darwin's dilemma: Why do species exist?
Each evolutionary step was however non-random: the direction was determined in advance and had a regular pattern (orthogenesis), and steps were not adaptive but part of a divine plan (theistic evolution). This left unanswered the question of why each step should occur, and Cope switched his theory to accommodate functional adaptation for each change. Still rejecting natural selection as the cause of adaptation, Cope turned to Lamarckism to provide the force guiding evolution. Finally, Cope supposed that Lamarckian use and disuse operated by causing a vitalist growth-force substance, "bathmism", to be concentrated in the areas of the body being most intensively used; in turn, it made these areas develop at the expense of the rest.
Alternatives to evolution by natural selection | Combined theories
Whereas scholars and theologians once held a symbolist mentality of the natural world as expressive of spiritual realities, intellectual thinking now regarded nature as a “coherent entity which could be systematically investigated by the senses. The idea of nature is that of a particular ordering of natural objects, and the study of nature the systematic investigation of that order.” The notion of order in nature implied a structure to the physical world whereby relationships between objects could be defined. According to Harrison, the twelfth century marked an important time in the Christian era when the world became invested with its own patterns of order—patterns based on networks of likeness or similarities among material things, which served to determine the character of a pre-modern knowledge of nature.
Book of Nature | Rediscovering the natural world
Fossil evidence of pre-Cambrian life has since been found, extending the history of life back for billions of years. Chapter X examines whether patterns in the fossil record are better explained by common descent and branching evolution through natural selection, than by the individual creation of fixed species. Darwin expected species to change slowly, but not at the same rate – some organisms such as "Lingula" were unchanged since the earliest fossils. The pace of natural selection would depend on variability and change in the environment. This distanced his theory from Lamarckian laws of inevitable progress. It has been argued that this anticipated the punctuated equilibrium hypothesis, but other scholars have preferred to emphasise Darwin's commitment to gradualism.
On the Origin of Species | Geological record
He argues in the book that selection is not the mechanism of evolution because it cannot be weighed on a balance, poured into a vial, or measured in specific units. Only a material component can be the mechanism of evolution, and this must be found in the physico-chemical processes.
Evolution Without Selection | Introduction
Three British men, all medically qualified and publishing between 1813 and 1819, William Lawrence, William Charles Wells and Prichard, addressed issues relevant to human evolution. All tackled the question of variation and race in humans; all agreed that these differences were heritable, but only Wells approached the idea of natural selection as a cause. Science historian Conway Zirkle has described Prichard as an evolutionary thinker who came very close "to explaining the origin of new forms through the operation of natural selection although he never actually stated the proposition in so many words." Prichard indicated Africa (indirectly) as the place of human origin, in this summary passage:
James Cowles Prichard | Evolution
This large interconnected population is now subject to many contradictory selection pressures and thus remains evolutionarily static until a disturbance separates populations, restarting the cycle. This cyclic life history pattern is dependent on three premises: that the ancestral range of most species is smaller than the ones now occupied, that biological communities have porous borders and are thus subject to invasion, and that species possess robust genotypes that allow them to colonize new habitats without evolution. Thus, many biological communities may be made up of organisms that despite their complex biological interactions have very little evolutionary history with each other.
Ecological fitting | Origin
All living creatures are derived from a common wild ancestor. With time and the help of humans or nature living beings has adapted to its surroundings by gradual changes whether it is visible or not. According to Darwin, there are two different categories that may cause wild ancestors to change to its modern or domesticated counterpart; natural selection and artificial selection. Natural selection as the name suggests, were environmentally driven, this occurs when more advantageous traits were passed down ensuring survival of the fittest. Whereas, artificial selection is done by humans intentionally breeding creatures to attain desirable traits. Both of these allows the wild ancestors to evolve.
Wild ancestors | Theory
Darwin gained extensive experience as he collected and studied the natural history of life forms from distant places. Through his studies, he formulated the idea that each species had developed from ancestors with similar features. In 1838, he described how a process he called natural selection would make this happen. The size of a population depends on how much and how many resources are able to support it. For the population to remain the same size year after year, there must be an equilibrium, or balance between the population size and available resources. Since organisms produce more offspring than their environment can support, not all individuals can survive out of each generation.
Introduction to evolution | Natural selection
"On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection" is the title of a journal article, comprising and resulting from the joint presentation of two scientific papers to the Linnean Society of London on 1 July 1858: "On The Tendency of Varieties to Depart Indefinitely from the Original Type" by Alfred Russel Wallace and an "Extract from an unpublished Work on Species" from Charles Darwin's "Essay" of 1844. The article also includes an "Abstract of a Letter" from Darwin to Asa Gray, and an introductory letter by Joseph Dalton Hooker and Charles Lyell.
On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection | Introduction
In both natural and artificial selection the variations are a result of random mutations, and the underlying genetic processes are essentially the same. Darwin carefully observed the outcomes of artificial selection in animals and plants to form many of his arguments in support of natural selection. Much of his book "On the Origin of Species" was based on these observations of the many varieties of domestic pigeons arising from artificial selection. Darwin proposed that if humans could achieve dramatic changes in domestic animals in short periods, then natural selection, given millions of years, could produce the differences seen in living things today.
Introduction to evolution | Artificial selection
Animal coloration, readily observable, soon provided strong and independent lines of evidence, from camouflage, mimicry and aposematism, that natural selection was indeed at work. The historian of science Peter J. Bowler wrote that Darwin's theory
Coloration evidence for natural selection | Context
One which I kept alive was certainly in this condition, the cause, as appeared on dissection, having been inflammation of the nictitating membrane. As frequent inflammation of the eyes must be injurious to any animal, and as eyes are certainly not necessary to animals having subterranean habits, a reduction in their size, with the adhesion of the eyelids and growth of fur over them, might in such case be an advantage; and if so, natural selection would aid the effects of disuse. (Charles Darwin, The Origin of Species)
Blindness in animals | Natural selection
Another factor that leads to the development of dimorphisms in species is natural selection. Natural selection focuses on traits and the environment's response to the traits in question; if the said trait increases the overall fitness of the individual possessing it, then it will be 'selected' and eventually become a permanent part of the population's gene pool. For example, depending on the food available in a shorebird specie's respective niche, bigger bill sizes may be favored in all individuals. This would essentially lead to monomorphism within the species but is subject to change once sexual selection acts on the trait.
Wader | Natural selection
Denton still accepts design and embraces a non-Darwinian evolutionary theory. He denies that randomness accounts for the biology of organisms; he has proposed an evolutionary theory which is a "directed evolution" in his book "Nature's Destiny" (1998). Life, according to Denton, did not exist until the initial conditions of the universe were fine-tuned (see Fine-tuned universe). Denton was influenced by Lawrence Joseph Henderson (1878-1942), Paul Davies and John D. Barrow who argued for an anthropic principle in the cosmos (Denton 1998, v, Denton 2005). His second book "Nature's Destiny" (1998) is his biological contribution to the anthropic principle debate, dominated by physicists.
Michael Denton | "Nature's Destiny"
In addition to the 80,000+ words of text, the book contains 425 illustrations by the author, who was also responsible for the design and layout of the entire book. It took six years to produce.
Katrina van Grouw | Unnatural Selection
This difficulty can be referred to as the absence or rarity of transitional varieties in habitat space. Another difficulty, related to the first one, is the absence or rarity of transitional varieties in time. Darwin commented that by the theory of natural selection "innumerable transitional forms must have existed," and wondered "why do we not find them embedded in countless numbers in the crust of the earth?" (For further discussion of these difficulties, see and Bernstein et al. and Michod.) The chapter then deals with whether natural selection could produce complex specialised structures, and the behaviours to use them, when it would be difficult to imagine how intermediate forms could be functional.
On the Origin of Species | Difficulties for the theory
Patterns can form for other reasons in the vegetated landscape of tiger bush and fir waves. Tiger bush stripes occur on arid slopes where plant growth is limited by rainfall. Each roughly horizontal stripe of vegetation effectively collects the rainwater from the bare zone immediately above it. Fir waves occur in forests on mountain slopes after wind disturbance, during regeneration. When trees fall, the trees that they had sheltered become exposed and are in turn more likely to be damaged, so gaps tend to expand downwind. Meanwhile, on the windward side, young trees grow, protected by the wind shadow of the remaining tall trees.
Patterns in nature | Pattern formation
The cause of this phenomenon is currently under debate; the most likely connection is with the mathematical theory of chaos and may give insights into the way patterns in sand form.
Oscillon | Introduction
The paper was reprinted and reviewed in several magazines including "The Zoologist", whose judgement was "on asking myself, 'What does all this prove?' the only answer I could make was, 'A possibility'." It was commented on in some reviews and letters. The Linnean Society President Thomas Bell in his presidential report of May 1859 wrote that "The year which has passed has not, indeed, been marked by any of those striking discoveries which at once revolutionize, so to speak, the department of science on which they bear". Years later, Darwin could only recall one review; Professor Haughton of Dublin claimed that "all that was new in them was false, and what was true was old." Despite illness, Darwin pressed on with writing the "abstract" of his "big book" on "Natural Selection"; this condensed version was published in November 1859 as "On the Origin of Species".
On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection | Impact of the publication
The authors' central argument against the concept of natural selection is what they call "the problem of selection-for". An extension of Gould and Lewontin's concept of spandrels, the authors note that certain traits of organisms always come together. The authors give examples: Because these traits come together, they are both correlated with fitness. Because exogenous selection processes posited by the theory of natural selection only have access to correlation, therefore, Fodor and Piattelli-Palmarini argue that the theory of natural selection "cannot predict/explain what traits the creatures in a population are selected-for", and so "the claim that selection is the mechanism of evolution cannot be true".
What Darwin Got Wrong | The problem of "selection-for"
The day after the funeral they moved to his sister-in-law's in Sussex, then on to Portsmouth and the Isle of Wight. At first they stayed in the King's Hotel, Shanklin, and on 30 July Darwin began writing an "abstract" of his book on "Natural Selection", planning a short paper in response to Hooker's urging to publish a scientific paper in the "Linnean" journal. They next rented a villa in Sandown and Darwin pressed on, with the facts he felt necessary to support his "abstract" expanding far beyond the thirty pages Hooker had originally suggested.
On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection | The reading
William Bateson in 1884 distinguished between the origin of novel variations and the action of natural selection ("Materials for the Study of Variation Treated with Especial Regard to Discontinuity in the Origin of Species").
Emergent evolution | Response to Darwin's "Origin of Species"
This had an implication that led to hypotheses that selective pressures imposed by the environment, such as predation and loss of resources, were instrumental to the cause of these trends. These ideas were reinforced by other studies, such as peramorphosis in the Puerto Rican Tree frog. Another reason could be generation time, or the lifespan of the species in question. When a species has a relatively short lifespan, natural selection favors evolution of paedomorphosis (e.g. Axolotl: 7–10 years). Conversely, in long lifespans natural selection favors evolution of peramorphosis (e.g. Irish Elk: 20–22 years).
Heterochrony | Peramorphosis
Charles Darwin published "On the Origin of Species" in 1859, arguing that evolution in nature must be driven by natural selection, just as breeds of domestic animals and cultivars of crop plants were driven by artificial selection. Darwin's theory radically altered popular and scientific opinion about the development of life. However, he lacked evidence and explanations for some critical components of the evolutionary process. He could not explain the source of variation in traits within a species, and did not have a mechanism of heredity that could pass traits faithfully from one generation to the next. This made his theory vulnerable; alternative theories were being explored during the eclipse of Darwinism; and so Darwinian field naturalists like Wallace, Bates and Müller looked for clear evidence that natural selection actually occurred.
Coloration evidence for natural selection | Context
The Causes of Evolution is a 1932 book on evolution by J.B.S. Haldane (1990 edition ), based on a series of January 1931 lectures entitled "A Re-examination of Darwinism". It was influential in the founding of population genetics and the modern synthesis.
The Causes of Evolution | Introduction
Dobzhansky concluded that such seasonal fluctuations were the result of natural selection at work, with temperature acting as the selecting agent. These masterful studies provided concrete support for the theory of natural selection, at the same time illustrating the fruitfulness of combining field and laboratory work in the study of evolution. Adaptive evolution occurs through the dominance and survival of competing genes within a species. This is caused by increasing the frequency of those alleles whose phenotypic effects selfishly promote their own reproduction. He also believed new species could not arise from single mutations and must be isolated from others of its species by time, geography, habitat, or breeding season.
Genetics and the Origin of Species | Natural selection and speciation
'In this world, it takes all the running you can do to keep in the same place...' In the cruel natural selection, species must evolve faster than others to gain a favorable position in the biological chain. Those who believe in the Red Queen hypothesis insist that humans should actively seek changes in order to rule nature.
Mr Love: Queen's Choice | <a href="Red%20Queen%20hypothesis">Red Queen Hypothesis</a>
The attitude and very striking colour-scheme thus combine to produce an extraordinary effect, whose deceptive appearance depends upon the breaking up of the entire form into two strongly contrasted areas of brown and white. Considered separately, neither part resembles part of a frog. Together in nature the white configuration alone is conspicuous. This stands out and distracts the observer's attention from the true form and contour of the body and appendages on which it is superimposed". Cott concluded that the effect was concealment "so long as the false configuration is recognized in preference to the real one". Such patterns embody, as Cott stressed, considerable precision as the markings must line up accurately for the disguise to work.
Coloration evidence for natural selection | Coincident disruptive coloration
... This summer will make the 20th year (!) since I opened my first-note-book, on the question how & in what way do species & varieties differ from each other.— I am now preparing my work for publication, but I find the subject so very large, that though I have written many chapters, I do not suppose I shall go to press for two years." He agreed with Wallace that "climatal conditions" had little effect, and wrote "It is really "impossible" to explain my views in the compass of a letter on the causes & means of variation in a state of nature; but I have slowly adopted a distinct & tangible idea.— Whether true or false others must judge".
Publication of Darwin's theory | Struggle for existence
According to Shapiro he "found an average of just over one error... per page by checking pages of this book at random." The historian Peter J. Bowler compared the book to anti-Darwinian and creationist works. He criticized the book for utilizing straw man arguments and presenting no valid scientific alternative to natural selection. Bowler noted that it is "easy to criticize an established theory, much more difficult to come up with a workable alternative... Hand waving about the creative power of the organism makes a nice-sounding philosophical position but a poor scientific theory".
Beyond Natural Selection | Reception
The combination of mutations creating new alleles at random, and natural selection picking out those that are useful, causes an adaptation. This is when organisms change in ways that help them to survive and reproduce. Many such changes, studied in evolutionary developmental biology, affect the way the embryo develops into an adult body.
Introduction to genetics | Genes and evolution
In 1202, Leonardo Fibonacci introduced the Fibonacci sequence to the western world with his book "Liber Abaci". Fibonacci presented a thought experiment on the growth of an idealized rabbit population.
Patterns in nature | History
The historian Robinson M. Yost explains that Darwinism went into eclipse during the 1890s. At that time, most zoologists felt that natural selection could not be the main cause of biological adaptation, and sought alternative explanations. As a result, many zoologists rejected both Batesian mimicry and Müllerian mimicry. Beddard, writes Yost, explained some problems in the theory of mimicry including that, given how many insect species there are, resemblances between species could arise by chance, and that mimicry was sometimes either useless or actually harmful. In Yost's view, Beddard wanted more evidence that natural selection really was responsible. Yost cites the staunch Darwinist Poulton's hostile review of 1892, which asserts the pre-eminence of Darwin's theory.
Animal Coloration (book) | Darwinism
E.B. Ford worked for many years on genetic polymorphism. Polymorphism in natural populations is frequent; the key feature is the occurrence together of two or more discontinuous forms of a species in some kind of balance. So long as the proportions of each form is above mutation rate, then selection must be the cause. As early as 1930 Fisher had discussed a situation where, with alleles at a single locus, the heterozygote is more viable than either homozygote. That is a typical genetic mechanism for causing this type of polymorphism. The work involves a synthesis of field observations, taxonomy, and laboratory genetics.
E. B. Ford | Ecological genetics
"I feel overawed by quantity where counting no longer makes sense. By unrepeatability within such a quantity. By creatures of nature gathered in herds, droves, species, in which each individual, while subservient to the mass, retains some distinguishing features. A crowd of people, birds, insects, or leaves is a mysterious assemblage of variants of certain prototype. A riddle of nature's abhorrence of exact repetition or inability to produce it. Just as the human hand cannot repeat its own gesture, I invoke this disturbing law, switching my own immobile herds into that rhythm." "Art will remain the most astonishing activity of mankind born out of struggle between wisdom and madness, between dream and reality in our mind."
Magdalena Abakanowicz | Quotes
Mechanical people but it is unknown if they were always that way or are creations of another organism. Their bodies are made of hourglass shaped copper. A couple times a day, they take in water through their bottom chamber and then dip themselves into lava lakes. This causes steam to pass through the narrow part of their body and into the upper chamber to power various gears that allow the being to function. This process creates a stone that contains several millions of channels that water can pass through. As time goes on, the channels alter, causing memories to be lost and formed.
The Bookmaking Habits of Select Species | Quatzoli
Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. It is a key mechanism of evolution, the change in the heritable traits characteristic of a population over generations. Charles Darwin popularised the term "natural selection", contrasting it with artificial selection, which in his view is intentional, whereas natural selection is not. Variation exists within all populations of organisms. This occurs partly because random mutations arise in the genome of an individual organism, and their offspring can inherit such mutations. Throughout the lives of the individuals, their genomes interact with their environments to cause variations in traits.
Natural selection | Introduction
However, he recommends that the student of nature determine the other "causes" as well, and notes that not all phenomena have an end, e.g., chance events. Aristotle saw that his biological investigations provided insights into the causes of things, especially into the final cause. George Holmes Howison, in "The Limits of Evolution" (1901), highlights "final causation" in presenting his theory of metaphysics, which he terms "personal idealism", and to which he invites not only man, but all (ideal) life:
Four causes | End
The book's introduction characterizes Darwinism by the "central claim" that "an unguided physical process can account for the emergence of all biological complexity and diversity". Contributor James Barham argues that "it is incorrect to simply equate Darwinism with belief in evolution." He distinguishes empirical Darwinism ("the idea that the formation of new species is due to random changes in individual organisms that happen to be 'selected' by the environment") from metaphysical Darwinism (the claim that "the theory of natural selection has successfully reduced all teleological and normative phenomena to the interplay of chance and necessity, thus eliminating purpose and value from our picture of the world").
Uncommon Dissent | Topics addressed
A pattern is a regularity in the world, in human-made design, or in abstract ideas. As such, the elements of a pattern repeat in a predictable manner. A geometric pattern is a kind of pattern formed of geometric shapes and typically repeated like a wallpaper design. Any of the senses may directly observe patterns. Conversely, abstract patterns in science, mathematics, or language may be observable only by analysis. Direct observation in practice means seeing visual patterns, which are widespread in nature and in art. Visual patterns in nature are often chaotic, never exactly repeating, and often involve fractals. Natural patterns include spirals, meanders, waves, foams, tilings, cracks, and those created by symmetries of rotation and reflection.
Pattern | Introduction
The zoologist Edward Bagnall Poulton, whose work is referred to throughout Beddard's book, reviewed "Animal Coloration" in "Nature" in 1892. Poulton is critical of Beddard and other authors, defending Darwin's theory of natural selection as "the most generally accepted explanation of organic evolution" and insisting that in "case after case" the Darwinian explanation turns out to be correct.
Animal Coloration (book) | "Nature"
Fluctuating selection is a mode of natural selection characterized by the fluctuation of the direction of selection on a given phenotype over a relatively brief period of evolutionary time. For example, a species of plant may come in two varieties: one which prefers wetter soil and one which prefers dryer soil. During a period of wet years, the wet variety will be more fit and produce more offspring, and thereby increase the frequency of wet-preferring plants. If this wet period is followed by drought, the dry variety will be selected for and its numbers will increase. As periods of dryness and wetness fluctuate, so too does selection on dry-preferring and wet-preferring plants.
Fluctuating selection | Introduction
The article was the first announcement of the Darwin–Wallace theory of evolution by natural selection; and appeared in print on 20 August 1858. The presentation of the papers spurred Darwin to write a condensed "abstract" of his "big book" on "Natural Selection". This was published in November 1859 as "On the Origin of Species".
On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection | Introduction