Crocodiles are protected in many parts of the world, and are farmed commercially. Their hides are tanned and used to make leather goods such as shoes and handbags; crocodile meat is also considered a delicacy. The most commonly farmed species are the saltwater and Nile crocodiles. Farming has resulted in an increase in the saltwater crocodile population in Australia, as eggs are usually harvested from the wild, so landowners have an incentive to conserve their habitat. Crocodile leather is made into wallets, briefcases, purses, handbags, belts, hats, and shoes. Crocodile oil has been used for various purposes. Snakes are also farmed, primarily in East and Southeast Asia, and their production has become more intensive in the last decade.
Commercial farming
Reptile
Reptile | Commercial farming
Yes - Crocodiles are farmed for the hides and meat; Snakes are also farmed for the purpose of research and the collection of venom for the creation of antivenom. Yes Yes, crocodiles are protected in many parts of the world, and are farmed commercially, snakes are also farmed primarily in East and Southeast Asia and Turtle farming is another known but controversial practice. Yes, crocodiles are protected in many parts of the world, and are farmed commercially.
hypothalamic amenorrhea will result in the increased secretion of thyroid stimulating hormone (tsh)
user
Sorry. I cannot find the answer based on the context.
assistant
what is hypopituitarism?
user
A decreased ("hypo") secretion of one or more of the eight hormones normally produced by the pituitary gland at the base of the brain.
assistant
what are the indications of it?
user
Insufficiency of follicle-stimulating hormone (FSH) and/or luteinizing hormone (LH) leading to sex hormone abnormalities. Growth hormone deficiency is more common in people with an underlying tumor than those with other causes.
assistant
how this can be treated?
user
Removing the underlying cause, treating the hormone deficiencies, and addressing any other repercussions that arise from the hormone deficiencies.
assistant
you mentioned a gland above, where is it located in human body?
user
The bottom of the hypothalamus at the base of the brain.
assistant
what is the size of this gland?
user
The size of a pea
assistant
what is the functions of anterior lobe of this gland?
user
Synthesizes and secretes hormones; regulates several physiological processes including stress, growth, reproduction, and lactation.
assistant
which hormones are synthesized by this lobe?
user
Growth hormone, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), thyroid stimulating hormone (TSH) etc
assistant
how is the posterior lobe different from the anterior lobe?
user
It store and secretes (but does not synthesize) the important endocrine hormones.
assistant
in which other animals this gland can be found?
user
All vertebrates such as mammals, amphibians, reptiles, and birds,
assistant
what is the clinical significance of this gland?
user
There are diseases involving the pituitary gland. The functions of the pituitary gland can be adversely affected by an over- or under-production of associated hormones. The Pituitary gland growth during adolescence can be altered by early life stress such as childhood maltreatment or maternal dysphoric behavior.
assistant
what is the third mentioned vertebrates from the above list?
user
They are tetrapod animals in the class Reptilia, comprising today's turtles, crocodilians, snakes, amphisbaenians, lizards, tuatara, and their extinct relatives
assistant
do they play any roles in cultures and religions?
user
Yes - In Egyptian history, the Nile cobra was worshipped as one of the gods and was also used for sinister purposes; In Hinduism, snakes are worshipped as gods; The turtle has a symbol of steadfastness and tranquility in religion, mythology, and folklore from around the world.
assistant
what  type of reproduction is common in this class?
user
Reptiles generally reproduce sexually; Most reptiles lay amniotic eggs
assistant
are they commercially farmed by humans?
user
Alligators and crocodiles were first farmed in the early 20th century, but the facilities involved were zoo-like and their main source of income was from tourism. By the early 1960s, the feasibility of farming these reptiles on a commercial scale was investigated in response to the decline of many crocodilian species around the world. Farming involves breeding and rearing captive stock on a self-contained basis, whereas ranching means the use of eggs, juveniles, or adults taken each year from the wild. Commercial organisations must satisfy the criteria of the Convention on International Trade in Endangered Species (CITES) by demonstrating that, in the area concerned, they do not adversely impact the wild population.
Crocodilia | Farming and ranching
These animals are rapidly becoming rare as their hides are used for handbags and leather (stripped of scales, of course). Numerous attempts have been made by both zoos and private reptile collectors to keep them, but in all cases, they have been reluctant to feed and prone to skin infections.
Acrochordus | Commercial exploitation
Crocodiles are protected in many parts of the world, and are farmed commercially. Their hides are tanned and used to make leather goods such as shoes and handbags; crocodile meat is also considered a delicacy. The most commonly farmed species are the saltwater and Nile crocodiles. Farming has resulted in an increase in the saltwater crocodile population in Australia, as eggs are usually harvested from the wild, so landowners have an incentive to conserve their habitat. Crocodile leather is made into wallets, briefcases, purses, handbags, belts, hats, and shoes. Crocodile oil has been used for various purposes. Snakes are also farmed, primarily in East and Southeast Asia, and their production has become more intensive in the last decade.
Reptile | Commercial farming
Reptiles generally reproduce sexually, though some are capable of asexual reproduction. All reproductive activity occurs through the cloaca, the single exit/entrance at the base of the tail where waste is also eliminated. Most reptiles have copulatory organs, which are usually retracted or inverted and stored inside the body. In turtles and crocodilians, the male has a single median penis, while squamates, including snakes and lizards, possess a pair of hemipenes, only one of which is typically used in each session. Tuatara, however, lack copulatory organs, and so the male and female simply press their cloacas together as the male discharges sperm.
Reptile | Reproduction
Demand for turtle meat and medicinal products is one of the main threats to turtle conservation in Asia. Though commercial breeding would seem to insulate wild populations, it can stoke the demand for them and increase wild captures. Even the potentially appealing concept of raising turtles at a farm to release into the wild is questioned by some veterinarians who have had some experience with farm operations. They caution that this may introduce into the wild populations infectious diseases that occur on the farm, but have not (yet) been occurring in the wild.
Reptile | Commercial farming
Crocodiles and alligators are farmed commercially. Their hides are tanned and used to make leather goods such as shoes and handbags; crocodile meat is also considered a delicacy. The most commonly farmed species are the saltwater and Nile crocodiles. Farming has resulted in an increase in the saltwater crocodile population in Australia, as eggs are usually harvested from the wild, so landowners have an incentive to conserve their habitat. Crocodile leather is made into wallets, briefcases, purses, handbags, belts, hats, and shoes. Crocodile oil has been used for various purposes. Iguana meat is popular in Mexico, a traditional food for thousands of years.
Human uses of reptiles | Food and other products
Parthenogenesis is a natural form of reproduction in which growth and development of embryos occur without fertilization. Reproduction in squamate reptiles is ordinarily sexual, with males having a ZZ pair of sex determining chromosomes, and females a ZW pair. However, various species, including the Colombian Rainbow boa ("Epicrates maurus"), "Agkistrodon contortrix" (copperhead snake) and "Agkistrodon piscivorus" (cotton mouth snake) can also reproduce by facultative parthenogenesis—that is, they are capable of switching from a sexual mode of reproduction to an asexual mode—resulting in production of WW female progeny. The WW females are likely produced by terminal automixis. Mole salamanders are an ancient (2.4–3.8 million year-old) unisexual vertebrate lineage.
Vertebrate | Parthenogenesis
In some of the "Cnemidophorus" species, there are no males, and they reproduce through parthenogenesis. This is well known in bees and aphids, but is very rare in vertebrates. Those species without males are now known to originate through hybridization, or interspecific breeding. Occasionally, a mating between a female of one species and a male of another produces a parthenogen, a female that is able to produce viable eggs that are genetically identical to her own cells. The lizards that hatch from these eggs are thus also parthenogens that can again produce identical eggs, resulting in an asexual, clonal population.
Cnemidophorus | Reproduction
Snake farming has been troubling for conservation in the past as it can lead to overexploitation of wild snakes and their natural prey to supply the farms. However, farming snakes can limit the hunting of wild snakes, while reducing the slaughter of higher-order vertebrates like cows. The energy efficiency of snakes is higher than expected for carnivores, due to their ectothermy and low metabolism. Waste protein from the poultry and pig industries is used as feed in snake farms. Snake farms produce meat, snake skin, and antivenom. Turtle farming is another known but controversial practice. Turtles have been farmed for a variety of reasons, ranging from food to traditional medicine, the pet trade, and scientific conservation.
Reptile | Commercial farming
On farms it is very common to use artificial insemination (AI), a medically assisted reproduction technique consisting of the artificial deposition of semen in the female's genital tract. It is used in cases where the spermatozoa can not reach the fallopian tubes or simply by choice of the owner of the animal. It consists of transferring, to the uterine cavity, spermatozoa previously collected and processed, with the selection of morphologically more normal and mobile spermatozoa. A cow's udder contains two pairs of mammary glands, (commonly referred to as "teats") creating four "quarters". The front ones are referred to as "fore quarters" and the rear ones "rear quarters".
Cattle | Reproduction
Asexual reproduction has been identified in squamates in six families of lizards and one snake. In some species of squamates, a population of females is able to produce a unisexual diploid clone of the mother. This form of asexual reproduction, called parthenogenesis, occurs in several species of gecko, and is particularly widespread in the teiids (especially "Aspidocelis") and lacertids ("Lacerta"). In captivity, Komodo dragons (Varanidae) have reproduced by parthenogenesis.
Reptile | Reproduction
Most reptiles lay amniotic eggs covered with leathery or calcareous shells. An amnion, chorion, and allantois are present during embryonic life. The eggshell (1) protects the crocodile embryo (11) and keeps it from drying out, but it is flexible to allow gas exchange. The chorion (6) aids in gas exchange between the inside and outside of the egg. It allows carbon dioxide to exit the egg and oxygen gas to enter the egg. The albumin (9) further protects the embryo and serves as a reservoir for water and protein. The allantois (8) is a sac that collects the metabolic waste produced by the embryo.
Reptile | Reproduction
contortrix" and "A. piscivorus" appear to be capable of this form of parthenogenesis. Reproduction in squamate reptiles is ordinarily sexual, with males having a ZZ pair of sex determining chromosomes, and females a ZW pair. However, the Colombian Rainbow boa, "Epicrates maurus", can also reproduce by facultative parthenogenesis resulting in production of WW female progeny. The WW females are likely produced by terminal automixis.
Squamata | Facultative parthenogenesis
Reptiles are almost all sexually dimorphic, and exhibit internal fertilization through the cloaca. Some reptiles lay eggs while others are ovoviviparous (animals that deliver live young). Reproductive organs are found within the cloaca of reptiles. Most male reptiles have copulatory organs, which are usually retracted or inverted and stored inside the body. In turtles and crocodilians, the male has a single median penis-like organ, while male snakes and lizards each possess a pair of penis-like organs.
Reproductive system | Reptiles
Tegus are among the most commercially exploited reptiles in the world. Up to 1,000,000 are harvested annually in their native Argentina for their hide and meat, and are particularly important as a source of income in rural or indigenous communities. Tegus can also be found in captivity, where they are bred for the pet trade. They are reported to be highly intelligent, becoming docile as they mature and in some cases even ignoring food in favor of social interaction. However, tegus have demanding husbandry requirements due to their large size. Within their native range, tegus are often thought of as pests, sometimes raiding chicken coops to feed on the eggs or fowl.
Salvator (lizard) | Economic importance and environmental impact
piscivorus" appear to be capable of this form of parthenogenesis. Reproduction in squamate reptiles is almost exclusively sexual. Males ordinarily have a ZZ pair of sex determining chromosomes, and females a ZW pair. However, the Colombian Rainbow boa ("Epicrates maurus") can also reproduce by facultative parthenogenesis resulting in production of WW female progeny. The WW females are likely produced by terminal automixis.
Snake | Facultative parthenogenesis
"Lerista muelleri" is classified as an oviparous reptile producing on average two eggs per clutch. Reproduction is predominantly determined by a combination of both seasonal and environmental factors. As with most oviparous reptiles, females select for sites offering the greatest protection from predation. In the more arid parts of the continent, eggs are likely to be deposited under the protection of sand, providing potential offspring with the benefits of security and ideal climatic conditions for incubation. Similar to their desert dwelling counterparts, individuals residing in more temperate climatic conditions, preferred environments are those likely to increase rates of incubation. This may include protection from predation, cold and wet conditions, under the cover of fallen debris, loose soil, fallen logs, leaf litter and rocks.
Wood mulch-slider | Reproduction
In reptiles, the cloaca consists of the "urodeum", "proctodeum", and "coprodeum". Some species have modified cloacae for increased gas exchange (see Reptile respiration and Reptile reproduction). This is where reproductive activity occurs.
Cloaca | Reptiles
Taking into account the registered farms that did not respond to the survey, as well as the unregistered producers, the total amounts must be significantly higher. Wild "C. trifasciata" are far more valuable than farmed-raised turtles of this species to both TCM practitioners and illegal wildlife traders. The gender of "C. trifasciata" is determined by gestation temperatures. Due to incubation temperatures at farms in warm lowlands, farms have only been able to produce females. This increased the price of wild-caught males to $20,000. The majority of farmed "C. trifasciata" are hybrids which can escape and establish populations, causing genetic pollution.
Golden coin turtle | Farming
The human population exploits a large number of other animal species for food, both of domesticated livestock species in animal husbandry and, mainly at sea, by hunting wild species. Marine fish of many species are caught commercially for food. A smaller number of species are farmed commercially. Invertebrates including cephalopods, crustaceans, and bivalve or gastropod molluscs are hunted or farmed for food. Chickens, cattle, sheep, pigs and other animals are raised as livestock for meat across the world. Animal fibres such as wool are used to make textiles, while animal sinews have been used as lashings and bindings, and leather is widely used to make shoes and other items.
Animal | In human culture
Adult males are slightly larger and more muscular than females, and have wider heads and necks. Visual sex determination can, however, be difficult, since the penis and testes are located internally between the rectum and urinary bladder in males and females have a single pair of mammae near the armpits. Fertilization occurs by contact transfer without intromission, similar to some lizards. Polygynous mating usually results in a single offspring; twins are possible but rare. The large foreclaws prevent mothers from grasping their newborns and they therefore have to carry the offspring until they are self-sufficient.
Anteater | Reproduction
Asexual reproduction is found in nearly half of the animal phyla. Parthenogenesis occurs in the hammerhead shark and the blacktip shark. In both cases, the sharks had reached sexual maturity in captivity in the absence of males, and in both cases the offspring were shown to be genetically identical to the mothers. The New Mexico whiptail is another example. Some reptiles use the ZW sex-determination system, which produces either males (with ZZ sex chromosomes) or females (with ZW or WW sex chromosomes). Until 2010, it was thought that the ZW chromosome system used by reptiles was incapable of producing viable WW offspring, but a (ZW) female boa constrictor was discovered to have produced viable female offspring with WW chromosomes.
Asexual reproduction | Examples in animals
Like amphibians, amniotes are air-breathing vertebrates, but they have complex eggs or embryos, including an amniotic membrane. Amniotes include reptiles (including dinosaurs and their descendants, birds) and mammals. Reptile eggs are often rubbery and are always initially white. They are able to survive in the air. Often the sex of the developing embryo is determined by the temperature of the surroundings, with cooler temperatures favouring males. Not all reptiles lay eggs; some are viviparous ("live birth"). Dinosaurs laid eggs, some of which have been preserved as petrified fossils.
Egg | Amniote eggs and embryos
This means reproduction occurs at two- to five-year intervals, the slowest in any reptile. Wild tuatara are known to be still reproducing at about 60 years of age; "Henry", a male tuatara at Southland Museum in Invercargill, New Zealand, became a father (possibly for the first time) on 23 January 2009, at the age of 111. The sex of a hatchling depends on the temperature of the egg, with warmer eggs tending to produce male tuatara, and cooler eggs producing females. Eggs incubated at have an equal chance of being male or female. However, at , 80% are likely to be males, and at , 80% are likely to be females; at all hatchlings will be females.
Tuatara | Reproduction
Like other Beryciformes, its reproduction is oviparous. It has little or no commercial value, and this combined with its timid, nocturnal nature makes population sizes and trends unknown. As such, it is listed as Data Deficient by the International Union for the Conservation of Nature.
Photoblepharon steinitzi | Introduction
Ranching, wild harvesting, and captive breeding are the three ways to obtain crocodilians recognized by the Convention on International Trade in Endangered Species (CITES) and the Crocodile Specialist Group (CSG). Alligators can be raised in captivity on farms or on ranches. Alligator farms breed alligators, whereas ranches incubate and rear hatchlings collected from the wild. Farms do collect eggs from the wild but they also keep breeding adults in their facilities to produce their own eggs whereas ranches do not. Farming and ranching operations typically return a certain percentage of juveniles to the wild at a size associated with a high survival rate, an approach that increases overall alligator survival rates from the low numbers of successful eggs and juveniles usually observed in the wild.
Crocodile farm | Methods
In 1986, the World Resource Institute estimated that 10.5 million reptile skins were traded legally. This total does not include the illegal trades of that year. Horned lizards are popularly harvested and stuffed. Some humans are making a conscious effort to preserve the remaining species of reptiles, however.
Lepidosauria | Interactions with humans
The same specimen of "S. prima" which had preserve a lizard in its stomach contents (NIGP 127587) also had several small eggs in its abdomen. Two eggs were preserved just in front of and above the pubic boot, and several more may lie underneath them on the slab. It is unlikely that they were eaten by the animal, as they are in the wrong part of the body cavity for the egg shells to have remained intact. It is more likely that they are unlaid eggs produced by the animal itself, proving the specimen to be a female. Each egg measured long by wide.
Sinosauropteryx | Reproduction
Eggs are produced by the females and are fertilised by sperm from another aggregate. There is no larval form and a single embryo develops in each individual in the aggregate. This later becomes detached from the aggregate and becomes a solitary individual ready to undergo asexual reproduction by budding again. The animal's rapid growth and this alternation of generations means that the population can build up rapidly when there is a plentiful food supply such as a bloom of phytoplankton. The salps themselves are eaten by fish, turtles, birds, jellyfish, heteropods, siphonophores and ctenophores.
Cyclosalpa bakeri | Biology
Once maturation of the ovum is complete, the rest of the animal degenerates, liberating the ovum itself. Small unciliated cells that form at the same time are interpreted to be spermatozoa. It has not yet been possible to observe fertilisation itself; the existence of the fertilisation membrane is currently taken to be evidence, however, that it has taken place. Putative eggs have been observed, but they degrade typically at the 32–64 cell stage. Neither embryonic development nor sperm have been observed. Despite lack of observation of sexual reproduction in lab, the genetic structure of the populations in wild is compatible with the sexual reproduction mode, at least for species of the analysed genotype H5.
Trichoplax | Reproduction
The reproduction of these animals is not well known, it is known that it is oviparous, with the female producing transparent or greenish eggs.
Scorpaena plumieri | Reproduction
The juvenile is a J1-J4, the J2 is what hatches out of the egg. J4 stage is where sexual differentiation occurs. Adult males do not feed or have a stylet. They are rare and not needed for reproduction. Parthenogenic reproduction may be the rule. H. Mangiferae lays eggs in the soil once mating has occurred.
Hemicriconemoides mangiferae | Life cycle and reproduction
Many species of reptiles have a seasonal breeding cycle. For example, in southern Australia, the Eastern Long Neck turtle brumates over winter before mating in spring. Herpetoculturists who wish to breed their reptiles may have to alter the environment in the vivarium to simulate seasons to encourage successful mating. Amphibians are easily bred in captivity. Due to their small size and low-maintenance requirements, large captive populations can be substantiated easily and for a low-cost compared to other organisms.
Herpetoculture | Breeding
In the latter group, many species, including all boas and most vipers, utilize this mode of reproduction. The degree of viviparity varies; some species simply retain the eggs until just before hatching, others provide maternal nourishment to supplement the yolk, and yet others lack any yolk and provide all nutrients via a structure similar to the mammalian placenta. The earliest documented case of viviparity in reptiles is the Early Permian mesosaurs, although some individuals or taxa in that clade may also have been oviparous because a putative isolated egg has also been found. Several groups of Mesozoic marine reptiles also exhibited viviparity, such as mosasaurs, ichthyosaurs, and Sauropterygia, a group that include pachypleurosaurs and Plesiosauria.
Reptile | Reproduction
Reptiles include a wide variety of snakes, and mammals include coyotes, bobcats, wild boar, spotted deer, and rabbits. Tropical crops raised here include sugar cane, coconuts, pineapple, bananas, mamey, and tamarind.
Hidalgo (state) | Ecology
Many reptiles are oviparous and will lay eggs if successfully mated. Breeders may use incubators to increase their chances of successful hatching. Reptilian incubators generally consist of a thermostat and hygrometer, plus various heating and misting devices, as to create a stable environment. Unlike most avian eggs, reptile eggs do not need to be turned; in the wild they are generally laid in mounds or underground and left to incubate.
Herpetoculture | Incubators
This species has been chosen as a model reptile for genomics by the National Human Genome Research Institute genome sequencing program. It was selected because of the ease and low cost of laboratory breeding and evolutionary value of the diversity of the genus. In 2011, the complete genome of this lizard was sequenced and published in "Nature". Before its genome was published, only mammals and three bird species had been sequenced among amniotes. The draft genome sequence is 1.78 Gb (compared with 2.0–3.6 Gb mammalian and 0.9–1.3 Gb avian genome assemblies), of which 27% are mobile elements such as LINEs.
Anolis carolinensis | Genomics
Many reptiles and the vast majority of invertebrates, most fish, amphibians and all birds are oviparous, that is, they lay eggs with little or no embryonic development taking place within the mother. In aquatic organisms, fertilization is nearly always external with sperm and eggs being liberated into the water (an exception is sharks and rays, which have internal fertilization). Millions of eggs may be produced with no further parental involvement, in the expectation that a small number may survive to become mature individuals. Terrestrial invertebrates may also produce large numbers of eggs, a few of which may avoid predation and carry on the species.
Birth | Other animals
Internal fertilization with many vertebrates (such as reptiles, some fish, and most birds) occur via cloacal copulation (see also hemipenis), while mammals copulate vaginally, and many basal vertebrates reproduce sexually with external fertilization. For primitive insects, the male deposits spermatozoa on the substrate, sometimes stored within a special structure; courtship involves inducing the female to take up the sperm package into her genital opening, but there is no actual copulation. In groups that have reproduction similar to spiders, such as dragonflies, males extrude sperm into secondary copulatory structures removed from their genital opening, which are then used to inseminate the female.
Sexual intercourse | Other animals
Reptiles (Late Latin for "creeping" or "crawling") do not have an aquatic larval stage, and in this way are unlike amphibians. Most reptiles are oviparous, although several species of squamates are viviparous, as were some extinct aquatic clades — the fetus develops within the mother, contained in a placenta rather than an eggshell. As amniotes, reptile eggs are surrounded by membranes for protection and transport, which adapt them to reproduction on dry land. Many of the viviparous species feed their fetuses through various forms of placenta analogous to those of mammals, with some providing initial care for their hatchlings. Some reptiles are more closely related to birds than other reptiles, and many scientists prefer to make Reptilia a monophyletic group which includes the birds.
Marine vertebrate | Reptiles
"S. vandami" is ovoviviparous. From two to six young are born alive in summer.
Van Dam's girdled lizard | Reproduction
Kok and colleagues hypothesize that males use their shovel-shaped snouts to excavate underground nesting chambers. Reproduction takes place during the wettest part of the year—excavation of egg chambers requires wet soils. The male advertisement call is a sequence of regular notes repeated about 17–23 times per minute. The dominant frequency is about 3300–3600 Hz. Female fecundity is 3–10 eggs.
Adenomera lutzi | Reproduction
The earliest amniotes, including stem-reptiles (those amniotes closer to modern reptiles than to mammals), were largely overshadowed by larger stem-tetrapods, such as "Cochleosaurus", and remained a small, inconspicuous part of the fauna until the Carboniferous Rainforest Collapse. This sudden collapse affected several large groups. Primitive tetrapods were particularly devastated, while stem-reptiles fared better, being ecologically adapted to the drier conditions that followed. Primitive tetrapods, like modern amphibians, need to return to water to lay eggs; in contrast, amniotes, like modern reptiles – whose eggs possess a shell that allows them to be laid on land – were better adapted to the new conditions.
Reptile | Rise of the reptiles
Male production depends on the season. Production of males is restricted during food shortages, creating short periods of male production with longer periods of female production. Males are produced by unfertilized eggs laid by the workers.
Scaptotrigona postica | Male Production
Scallops of this species are collected commercially for human consumption using such techniques as the Rapido trawl.
Pecten jacobaeus | Commercial value
This produces a symmetrical electric field around its body. Nearby objects distort this field, and it can sense the distortion on its skin. "G. niloticus" females lay their eggs in floating nests up to across. The adults continue to guard the young after hatching. The sperm cells don't have a flagellum, and therefore moves like an amoeba instead.
Gymnarchus | Description and biology
Inside the eggs, the embryos use nutrients from the yolk. Parental care is uncommon and the female usually abandons the eggs after laying them. Brooding and protection of eggs does occur in some species. The female prairie skink uses respiratory water loss to maintain the humidity of the eggs which facilitates embryonic development. In lace monitors, the young hatch close to 300 days, and the female returns to help them escape the termite mound were the eggs were laid. Around 20 percent of lizard species reproduce via viviparity (live birth). This is particularly common in Anguimorphs. Viviparous species give birth to relatively developed young which look like miniature adults.
Lizard | Reproduction and lifecycle
Reptiles are tetrapod animals from the class Reptilia comprising today's turtles, crocodilians, snakes, amphisbaenians, lizards, tuatara, and their extinct relatives. Reptiles are vertebrates, creatures that either have four limbs or, like snakes, are descended from four-limbed ancestors. Unlike amphibians, reptiles do not have an aquatic larval stage. Most reptiles are oviparous, although several species of squamates are viviparous, as were some extinct aquatic clades — the fetus develops within the mother, contained in a placenta rather than an eggshell. As amniotes, reptile eggs are surrounded by membranes for protection and transport, which adapt them to reproduction on dry land. There are about 16 species of reptiles found in Czech republic.
List of herpetofauna of the Czech Republic | Reptile
Commercial butterfly farmers plant native plants on the property, providing food sources for the caterpillars.
Commercial butterfly breeding | Economic development in Third World countries
Other groups include aquatic reptiles, amphibians, and miscellaneous invertebrates, such as echinoderms and jellyfish. They are separately graphed at the top right of this section, since they do not contribute enough volume to show clearly on the main graph. Commercially harvested echinoderms include sea cucumbers and sea urchins. In China, sea cucumbers are farmed in artificial ponds as large as .
Aquaculture | Other groups
Crocodiles are either farmed or wild-caught. In Northern and Western Australia crocodile farms carry out ranching which includes captive breeding and harvesting of eggs from the wild. Eggs are collected and landowners sell the eggs to local farms to breed. In 2018 this method also became legal in Queensland. On a crocodile farm, crocodiles are grown and prepared for slaughter before their skin is removed, treated, and sent to be tanned in specialist tanneries and used in the manufacture of commercial goods. The main farm income is in crocodile skin for the fashion industry. It is important the skin is of good quality to achieve the highest revenue possible.
Crocodile skin | Farming
The intentional cultivation of arthropods and other small animals for human food, referred to as minilivestock, is now emerging in animal husbandry as an ecologically sound concept. Commercial butterfly breeding provides Lepidoptera stock to butterfly conservatories, educational exhibits, schools, research facilities, and cultural events. However, the greatest contribution of arthropods to human food supply is by pollination: a 2008 study examined the 100 crops that FAO lists as grown for food, and estimated pollination's economic value as €153 billion, or 9.5 per cent of the value of world agricultural production used for human food in 2005. Besides pollinating, bees produce honey, which is the basis of a rapidly growing industry and international trade.
Arthropod | Interaction with humans
"C. tennentii" lays eggs and is a sexually reproducing animal.
Leaf-nosed lizard | Reproduction
They are characterised by a white strip starting at their nose and leading down their neck, as well as a more rigged shell. In Australia, the public require a basic reptiles licence to purchase these animals; taking from the wild is strictly prohibited.
Emydura | Introduction
Scientists often classify animal reproduction according to the degree of development that occurs before the new individuals are expelled from the adult body, and by the yolk which the egg provides to nourish the embryo.
Egg | Scientific classifications
Reptiles (Late Latin for "creeping" or "crawling") do not have an aquatic larval stage, and in this way are unlike amphibians. Most reptiles are oviparous, although several species of squamates are viviparous, as were some extinct aquatic clades — the fetus develops within the mother, contained in a placenta rather than an eggshell. As amniotes, reptile eggs are surrounded by membranes for protection and transport, which adapt them to reproduction on dry land. Many of the viviparous species feed their fetuses through various forms of placenta analogous to those of mammals, with some providing initial care for their hatchlings. Some reptiles are more closely related to birds than other reptiles, and many scientists prefer to make Reptilia a monophyletic group which includes the birds.
Marine life | Reptiles
In 2012, facultative parthenogenesis was reported in wild vertebrates for the first time by US researchers amongst captured pregnant copperhead and cottonmouth female pit-vipers. The Komodo dragon, which normally reproduces sexually, has also been found able to reproduce asexually by parthenogenesis. A case has been documented of a Komodo dragon reproducing via sexual reproduction after a known parthenogenetic event, highlighting that these cases of parthenogenesis are reproductive accidents, rather than adaptive, facultative parthenogenesis. Some reptile species use a ZW chromosome system, which produces either males (ZZ) or females (ZW). Until 2010, it was thought that the ZW chromosome system used by reptiles was incapable of producing viable WW offspring, but a (ZW) female boa constrictor was discovered to have produced viable female offspring with WW chromosomes.
Parthenogenesis | Squamata
In groups such as dragonflies and many spiders, males extrude sperm into secondary copulatory structures removed from their genital opening, which are then used to inseminate the female (in dragonflies, it is a set of modified sternites on the second abdominal segment; in spiders, it is the male pedipalps). In advanced groups of insects, the male uses its aedeagus, a structure formed from the terminal segments of the abdomen, to deposit sperm directly (though sometimes in a capsule called a "spermatophore") into the female's reproductive tract. Other animals reproduce sexually with external fertilization, including many basal vertebrates. Vertebrates (such as reptiles, some fish, and most birds) reproduce with internal fertilization through cloacal copulation (see also hemipenis), while mammals copulate vaginally.
Mating | Animals
Males maintain small mating territories, few centimeters in size. When a female enters the territory, the male initiates a mating dance and eventually deposits a spermatophore, which is then picked up by the females. Fecundity is 20–40 eggs. The development from egg stage into maturity takes 10 to 24 months and involves three molts; molting may involve building a silk nest. The total life span is 3–4 years.
Chelifer cancroides | Reproduction
Based on an observation from Chiapas, breeding takes place underwater and involves axillar amplexus. Male advertisement call is a brief and rapid trill. Males were observed calling underwater and from within small holes and crevices in the splash-zone of waterfalls.
Plectrohyla avia | Reproduction
Like vertebrates, most invertebrates reproduce at least partly through sexual reproduction. They produce specialized reproductive cells that undergo meiosis to produce smaller, motile spermatozoa or larger, non-motile ova. These fuse to form zygotes, which develop into new individuals. Others are capable of asexual reproduction, or sometimes, both methods of reproduction.
Invertebrate | Reproduction
The farming of this "luscious reptile", known in Japan as "suppon", was already developed on an industrial scale in that country by the late 19th century. Due to rising demand and overhunting, the price of "Pelodiscus sinensis" in China skyrocketed by the mid-1990s; large-scale turtle farming in China and neighboring countries; raising this species by hundreds of millions was the response, with prices soon returning to a more affordable level. Another species, "Palea steindachneri", is farmed in China, as well, but on a much smaller scale (with farm herds measured in hundreds of thousands, rather than hundreds of millions).
Trionychidae | As food
The eggs were small compared to the size of the mother (the "Mrs T" specimen weighed between and ), also more like modern reptiles than birds. David Unwin, a co-author of the paper, suggested that "Darwinopterus" probably laid many small eggs at a time and buried them, and that juveniles could fly upon hatching, requiring little to no parental care. These results imply that reproduction in pterosaurs was more like that in modern reptiles and significantly differed from reproduction in birds. However, in 2015, the counterplate of the specimen was reported, IVPP V18403, which showed a single additional egg present in the body, indicating that there were two active ovaries, producing a single egg at a time.
Darwinopterus | Reproduction
At 20 °C, "Oikopleura cophocerca" builds and discards two houses each day. Appendicularians are hermaphrodites and sexual reproduction is the only means of reproduction in this species. The testes ripen first and sperm is shed into the sea. When the ovary ripens, the body wall of the animal ruptures to release the eggs and the animal dies in the process. The development of the zygote is rapid and direct and the embryo starts to feed and secrete a mucus net within twenty four hours.
Oikopleura cophocerca | Biology
The general build was heavy in all forms, though otherwise very similar to that of early reptiles. The skin, at least in the more advanced forms probably had a water-tight epidermal horny overlay, similar to the one seen in today's reptiles, though they lacked horny claws. In chroniosuchians and some seymouriamorphs, like "Discosauriscus", dermal scales are found in post-metamorphic specimens, indicating they may have had a "knobbly", if not scaly, appearance. Seymouriamorphs reproduced in amphibian fashion with aquatic eggs that hatched into larvae (tadpoles) with external gills; it is unknown how other tetrapods traditionally assigned to Reptiliomorpha reproduced.
Reptiliomorpha | Physiology
Males become highly territorial during breeding season. They discourage intruding males by brightening their red heads and doing "push-ups". Each tries to attract a female by inflating his throat and drawing attention to his handsomely colored head. Oviparous; about 10—20 eggs are laid, buried in moist soil. The eggs are long, spindle-shaped and covered with a leathery skin. They hatch in about 6–7 weeks. They are able to breed at about 1 year old.
Oriental garden lizard | Reproduction
The wild eggs are gathered by a variety of artisianal methods, and because success is not predictable, the production varies as well. Commercial fishing for areolate grouper done with long lines and hand lines. While its popularity for food has led to some species being threatened, currently no threat to the survival of "E. areolatus" exists. The table at right shows the amount of areolate grouper produced by farming between 1992 and 2004 and the amount produced by capture in Saudi Arabia (Indian Ocean) between 1996 and 2004, according to the Food and Agriculture Organization of the United Nations
Areolate grouper | Commercial production
Reptiles are tetrapod animals in the class Reptilia, comprising today's turtles, crocodilians, snakes, amphisbaenians, lizards, tuatara, and their extinct relatives. The study of these traditional reptile orders, historically combined with that of modern amphibians, is called herpetology. Because some reptiles are more closely related to birds than they are to other reptiles (e.g., crocodiles are more closely related to birds than they are to lizards), the traditional groups of "reptiles" listed above do not together constitute a monophyletic grouping or clade (consisting of all descendants of a common ancestor). For this reason, many modern scientists prefer to consider the birds part of Reptilia as well, thereby making Reptilia a monophyletic class, including all living diapsids.
Reptile | Introduction
However, stunted sexual maturity appears to occur in populations at opposite extremes, both where crocodiles are thought to be overpopulated and where they are overly reduced to heavy hunting, sometimes with females laying eggs when they measure as small as although it is questionable whether such clutches would bear healthy hatchlings. According to Bourquin (2008), the average breeding female in southern Africa is between . Earlier studies support that breeding is often inconsistent in females less than and clutch size is smaller, a female at reportedly never lays more than 35 eggs, while a female measuring can expect a clutch of up to 95 eggs.
Nile crocodile | Reproduction
Embryos are nourished via a placenta-like structure. A minority of lizards have parthenogenesis (reproduction from unfertilised eggs). These species consist of all females who reproduce asexually with no need for males. This is known in occur in various species of whiptail lizards. Parthenogenesis was also recorded in species that normally reproduce sexually. A captive female Komodo dragon produced a clutch of eggs, despite being separated from males for over two years.
Lizard | Reproduction and lifecycle
Individuals in this species are typically either male or female, with some small portion protandrous hermaphrodites, maturing as males and later in life reproducing as females. They reproduce by broadcast spawning, with individuals releasing eggs and sperm into the water to achieve fertilization. Fertilized eggs develop into free-swimming larva, These develop into planktonic veligers, which feed on tiny phytoplankton. In the presence of appropriate chemical cues, a veliger will settle to the bottom, attach itself to a rocky substrate and become a juvenile.
Barbatia reeveana | Life history
The males call from dense, low grass that grow on soils flooded by a few centimetres of water. The advertisement call is quiet, high-pitched buzzing. The eggs are placed in small batches in transversally folded grass leaves, glued together by jelly. The newly metamorphosed froglets measure .
Afrixalus weidholzi | Reproduction
Reproduction in snakes is almost exclusively sexual. Males ordinarily have a ZZ pair of sex determining chromosomes and females a ZW pair. However, it was recently shown that "E. maurus" is capable of reproducing by facultative parthenogenesis resulting in production of WW female progeny. The WW females were likely produced by terminal automixis (see diagram), a type of parthenogenesis in which two terminal haploid products of meiosis fuse to form a zygote, which then develops into a daughter progeny. This is only the third genetically confirmed case of consecutive virgin births of viable offspring from a single female within any vertebrate lineage.
Epicrates maurus | Parthenogenesis
Because these snakes are oviparous the female will leave her eggs after laying them. These animals do not present parental care traits.
Imantodes cenchoa | Reproduction
Various types of marine gavialid crocodilians remained widespread as recently as the Late Miocene. Currently, of the approximately 12,000 extant reptile species and subspecies, only about 100 are classed as marine reptiles: extant marine reptiles include marine iguanas, sea snakes, sea turtles and saltwater crocodiles.
Marine reptile | Introduction
It can be almost impossible to differentiate males from females. Males in a group can be determined as they may become more territorial. Reproduction involves females laying roes into caves or hollows of roots. There is a high rate of mortality until the spawn are five centimeters long. The reason for this is unknown.
Pterygoplichthys gibbiceps | Reproduction
When the platypus was first encountered by European naturalists, they were divided over whether the female laid eggs. This was not confirmed until 1884, when William Hay Caldwell was sent to Australia, where, after extensive searching assisted by a team of 150 Aborigines, he managed to discover a few eggs. Mindful of the high cost per word, Caldwell tersely wired London, "Monotremes oviparous, ovum meroblastic." That is, monotremes lay eggs, and the eggs are similar to those of reptiles in that only part of the egg divides as it develops. The species exhibits a single breeding season; mating occurs between June and October, with some local variation taking place between different populations across its range.
Platypus | Reproduction
Breeding takes place cyclically in spring and summer. Male "G. marginata" are capable of producing a pheromone which attracts females, although this is only believed to be effective over short distances. They then transfer sperm to the female using their gonopods, specially modified legs. After fertilisation, the females lay 70–80 eggs, each about 1 mm long, and each wrapped singly in a capsule of digested earth. The eggs hatch after a period of about two months, with the duration depending on factors including temperature. Development lasts for up to three years, and involves nine moults, following which moults occur periodically as adults.
Glomeris marginata | Reproduction and life cycle
Reproduction takes place entirely in fresh water, and breeding takes place all year round; there does not seem to be a breeding season. The young undergo direct development, hatching as juveniles, without passing through any larval stages. The females carry the eggs and protect the young who stay with their mother for a period after hatching.
Guinotia dentata | Reproduction
Although the cost of operating an open cycle operation is comparable to closed cycle, the goal of an open cycle operation is the overall health of the species, rather than economic profit. Captive breeding and ranching operations provide more incentive to protect natural populations and are important contributors to the success of crocodilian populations.
Crocodile farm | Methods
Due to the close contact of poultry in large-scale productions, this capability is often acutely realized.
Menoponidae | Biology
Reproduction in spring and autumn at water temperatures above 15 °C, eggs (diameter 1.2-1.7 mm) are laid in mostly elongate capsules of 8–15 mm width, each strain containing 12-40 eggs, fixed to aquatic plants, embryos are reddish with transparent shells, juveniles hatch after 14–16 days, life span up to 3 years. Self-fertilization is possible, one single released animal can establish a stable population, but only 5% of the juveniles in self-fertilized eggs will hatch.
Planorbarius corneus | Reproduction
Sexual reproduction occurs through the clustered or scattered deposition of spermatophores by male adults. Stimulation of spermatophore deposition by female pheromones has been demonstrated in "Sinella curviseta". Mating behaviour can be observed in Symphypleona. Among Symphypleona, males of some Sminthuridae use a clasping organ located on their antenna. Many collembolan species, mostly those living in deeper soil horizons, are parthenogenetic, which favours reproduction to the detriment of genetic diversity and thereby to population tolerance of environmental hazards. Parthenogenesis (also called thelytoky) is under the control of symbiotic bacteria of the genus "Wolbachia", which live, reproduce and are carried in female reproductive organs and eggs of Collembola.
Springtail | Reproduction
There are long-standing differences and disputes between herpetoculturists and professional herpetologists. With professional herpetology's increasing focus on scientific research, including conservation biology, some herpetologists believe that herpetoculturists are part of the problem: that collecting specimens from the wild for the live animal trade is having an adverse impact on wild populations. While many captive bred reptiles and amphibians are offered for sale at pet stores and reptile shows such as bearded dragons, corn snakes and leopard geckos, many animals sold are still removed from the wild. Complicating the matter further is the growing problem of exotic species escaping or being released into the wild where they occasionally establish populations outside of their natural ranges, becoming invasive species.
Herpetoculture | Controversy
Herpetoculture is the keeping of live reptiles and amphibians in captivity, whether as a hobby or as a commercial breeding operation. "Herps" is an informal term for both reptiles and amphibians. It is undertaken by people of all ages and from all walks of life, including career herpetologists, professional reptile or amphibian breeders, and casual hobbyists.
Herpetoculture | Introduction
Common lizard and adder may be seen on sunny days.
Snows Farm Nature Reserve | Reptiles
Animals are commonly classified by their manner of reproduction, at the most general level distinguishing egg-laying (Latin. "oviparous") from live-bearing (Latin. "viviparous"). These classifications are divided into more detail according to the development that occurs before the offspring are expelled from the adult's body. Traditionally: The term hemotropic derives from the Latin for blood-feeding, contrasted with histotrophic for tissue-feeding.
Egg | Egg-laying reproduction
The sex of most amniote vertebrates, such as mammals and birds, is determined genetically. However, some reptiles have temperature-dependent sex determination, where sex is permanently determined by thermal conditions experienced during the middle third of embryonic development. The sex of crocodilians and sphenodontians is exclusively determined by temperature. In contrast, squamates (lizards and snakes) and turtles exhibit both genotypic sex determination and temperature-dependent sex determination, although temperature dependence is much more common in turtles than in squamates.
Environmental sex determination | Vertebrates
Polyandry has been observed in "B. dorsalis". For females, there is typically a re-mating refractory period. The length of this period does not vary based on whether the female is mating with a virgin or non-virgin male. However, when there was a refractory period, females lay more eggs. Females who were exposed to two males continuously without a refractory period in between lay fewer eggs, but still lay more eggs than females with only one male. Therefore, there appears to be a reproductive benefit for females with polyandry. Reproductive senescence does appear to be present in this species, as male and female age correlates negatively with the rate of fertilization.
Bactrocera dorsalis | Mating
"Medauroidea extradentata" is mainly parthenogenetic, meaning they are asexual, making males very rare in the species. The female drops hundreds of eggs onto the forest floor, these eggs hatch in a few months. The eggs of this species are mottled with black and white and capped with black.
Medauroidea extradentata | Reproduction
Crocodiles lay many eggs that are small proportional to adult body size. Birds lay fewer, larger, eggs. The Two Medicine troodont was intermediate, laying an egg of about 0.5 kg for a 50 kg adult. This is 10 times larger than reptiles of the same mass, but two troodont eggs are roughly equivalent to the 1.1 kg egg predicted for a 50 kg bird. Varricchio et al. also found evidence for iterative laying, where the adult might lay a pair of eggs every one or two days, and then ensured simultaneous hatching by delaying brooding until all eggs were laid.
Stenonychosaurus | Reproduction
The archaeological and genetic data suggest that long-term bidirectional gene flow between wild and domestic stocks – including donkeys, horses, New and Old World camelids, goats, sheep, and pigs – was common. Given its importance to humans and its value as a model of evolutionary and demographic change, domestication has attracted scientists from archaeology, paleontology, anthropology, botany, zoology, genetics, and the environmental sciences. Among birds, the major domestic species today is the chicken, important for meat and eggs, though economically valuable poultry include the turkey, guineafowl and numerous other species. Birds are also widely kept as cagebirds, from songbirds to parrots.
Domestication | Introduction
The Diadectomorphans generally being large animals would have had correspondingly large eggs, unable to survive on land. Fully terrestrial life was achieved with the development of the amniote egg, where a number of membranous sacks protect the embryo and facilitate gas exchange between the egg and the atmosphere. The first to evolve was probably the allantois, a sack that develops from the gut/yolk-sack. This sack contains the embryo's nitrogenous waste (urea) during development, stopping it from poisoning the embryo. A very small allantois is found in modern amphibians. Later came the amnion surrounding the fetus proper, and the chorion, encompassing the amnion, allantois, and yolk-sack.
Reptiliomorpha | From aquatic to terrestrial eggs
Compared to adults, young prefer and are more skilled at climbing. Females become sexually mature by 150 days, and males by 210 days. Like many chameleons and other lizards, females can store sperm after mating once so that more fertile eggs may be laid months later. Laying is taxing on females and depletes their fat reserves. Females subsequently eat as much as the stomach capacity allows. In captive settings, females should be allowed to eat as much as they want after laying. Due to the especially advanced state of embryos and eggs by the time they are laid, it has been suggested that this species is in the process of evolving ovoviviparity.
Namaqua chameleon | Reproduction
The adult males and females form monogamous pairs, they are an ovoviviparous species, in which the males brood the fertilised eggs in a brood pouch situated under his tail. The brood pouch protects the dorsal surface and side of the egg mass, leaving the ventral surface exposed. Males are capable of once they attain a total length of . The eggs mass consists of 2–17 transverse rows within a gelatinous matrix.
Corythoichthys amplexus | Reproduction
These animals generally reproduce asexually by budding, though sexual reproduction does occur in some groups.
Coelenterata | Characteristics
Through the compilation and analysis of a database of nearly three dozen birds and reptiles, and comparison with existing data about the anatomy of "Coelophysis" Rinehart "et al." (2009) drew the following conclusions. It was estimated that average egg of "Coelophysis" was 31–33.5 millimeters across its minor diameter, and that each female would lay between 24–26 eggs in each clutch. The evidence suggested that some parental care was necessary to nurture the relatively small hatchlings during the first year of life, where they would reach 1.5 meters in length by the end of their first growth stage. "Coelophysis bauri" invested as much energy in reproduction as other extinct reptiles of its approximate size.
Coelophysis | Reproduction
As of 1995, the following reptile species are recorded as being present: the shingle back lizard and a species of dragon lizard.
Point Labatt | Fauna
The amniotic sac (10) contains amniotic fluid (12) which protects and cushions the embryo. The amnion (5) aids in osmoregulation and serves as a saltwater reservoir. The yolk sac (2) surrounding the yolk (3) contains protein and fat rich nutrients that are absorbed by the embryo via vessels (4) that allow the embryo to grow and metabolize. The air space (7) provides the embryo with oxygen while it is hatching. This ensures that the embryo will not suffocate while it is hatching. There are no larval stages of development. Viviparity and ovoviviparity have evolved in many extinct clades of reptiles and in squamates.
Reptile | Reproduction
The female may lay several eggs at a time, but a clutch of two is common, particularly in coastal areas. Clutch sizes may be larger in other geographical ranges.
Tropidurus torquatus | Reproduction