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Modes Of Reproduction
Animals make use of a variety of modes of reproduction to produce their young. Traditionally this variety was classified into three modes, oviparity (embryos in eggs), viviparity (young born live), and ovoviviparity (intermediate between the first two). However, each of those so-called traditional modes covered a wide range of diverse reproductive strategies. The biologist Thierry Lodé has accordingly proposed five modes of reproduction based on the relationship between the zygote (the fertilised egg) and the parents. His revised modes are ovuliparity, with external fertilisation; oviparity, with internal fertilisation of large eggs containing a substantial nutritive yolk; ovo-viviparity, that is oviparity where the zygotes are retained for a time in a parent's body, but without any sort of feeding by the parent; histotrophic viviparity, where the zygotes develop in the female's oviducts, but are fed on other tissues; and hemotrophic viviparity, where the developing embryos are fe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pollo De Aguilucho Cenizo (Circus Pygargus)
Pollo may refer to: * chicken in Spanish and Italian languages * pollo, or polo, is a rice dish in the Persian language People *Secondo Pollo (1908-1941), Italian priest *Stefanaq Pollo (1924-1977), Albanian academic *Genc Pollo (born 1963), Albanian politician *Pollo (footballer) (born 1983), Spanish footballer *Pollo Del Mar, American drag queen *Pollo (band), Brazilian rap group Places *Pollos, municipality in Spain *Los Pollos, town in Panama See also * *List of chicken restaurants This is a list of notable chicken restaurants. This list includes casual dining, fast casual and fast food restaurants which typically specialize in chicken dishes such as fried chicken, chicken and waffles, chicken sandwiches or chicken a ... * List of chicken dishes {{dab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frog
A frog is any member of a diverse and largely semiaquatic group of short-bodied, tailless amphibian vertebrates composing the order (biology), order Anura (coming from the Ancient Greek , literally 'without tail'). Frog species with rough skin texture due to wart-like parotoid glands tend to be called toads, but the distinction between frogs and toads is informal and purely cosmetic, not from taxonomy (biology), taxonomy or evolutionary history. Frogs are widely distributed, ranging from the tropics to subarctic regions, but the greatest concentration of species diversity is in tropical rainforest and associated wetlands. They account for around 88% of extant amphibian species, and are one of the five most diverse vertebrate orders. The oldest fossil "proto-frog" ''Triadobatrachus'' is known from the Early Triassic of Madagascar (250Myr, million years ago), but molecular clock, molecular clock dating suggests their divergent evolution, divergence from other amphibians may exte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryo
An embryo ( ) is the initial stage of development for a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm cell. The resulting fusion of these two cells produces a single-celled zygote that undergoes many cell divisions that produce cells known as blastomeres. The blastomeres (4-cell stage) are arranged as a solid ball that when reaching a certain size, called a morula, (16-cell stage) takes in fluid to create a cavity called a blastocoel. The structure is then termed a blastula, or a blastocyst in mammals. The mammalian blastocyst hatches before implantating into the endometrial lining of the womb. Once implanted the embryo will continue its development through the next stages of gastrulation, neurulation, and organogenesis. Gastrulation is the formation of the three germ layers that will form all of the different parts of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastrotheca Ovifera
''Gastrotheca ovifera'' (vernacular names: pouched frog and giant marsupial frog; or ) is a species of frog in the family Hemiphractidae. It is endemic to northern Venezuela and is known from the Venezuelan Coastal Range, including Sierra de Aroa. ''Gastrotheca ovifera'' occurs in cloud forests at elevations of above sea level. It is associated with bromeliads where it hides, especially during dry periods. The eggs are carried on the female's back and have direct development (i.e., there is no free-living larval stage). This species can be locally abundant, but it has declined in many places where it used to be common. It is threatened by habitat loss caused by agriculture, logging, and infrastructure development. However, it has also declined in protected areas such as the Henri Pittier National Park Henri Pittier National Park is the oldest national park in Venezuela, originally created in 1937 under the name of ''Rancho Grande'' by decree of President Eleazar López Co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marsupial
Marsupials are a diverse group of mammals belonging to the infraclass Marsupialia. They are natively found in Australasia, Wallacea, and the Americas. One of marsupials' unique features is their reproductive strategy: the young are born in a relatively undeveloped state and then nurtured within a pouch on their mother's abdomen. Extant marsupials encompass many species, including Kangaroo, kangaroos, Koala, koalas, Opossum, opossums, Phalangeriformes, possums, Tasmanian devil, Tasmanian devils, Wombat, wombats, Wallaby, wallabies, and Bandicoot, bandicoots. Marsupials constitute a clade stemming from the last common ancestor of extant Metatheria, which encompasses all mammals more closely related to marsupials than to Placentalia, placentals. The evolutionary split between placentals and marsupials occurred 125-160 million years ago, in the Middle Jurassic-Early Cretaceous period. Presently, close to 70% of the 334 extant marsupial species are concentrated on the Australian ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammal
A mammal () is a vertebrate animal of the Class (biology), class Mammalia (). Mammals are characterised by the presence of milk-producing mammary glands for feeding their young, a broad neocortex region of the brain, fur or hair, and three Evolution of mammalian auditory ossicles, middle ear bones. These characteristics distinguish them from reptiles and birds, from which their ancestors Genetic divergence, diverged in the Carboniferous Period over 300 million years ago. Around 6,640 Neontology#Extant taxon, extant species of mammals have been described and divided into 27 Order (biology), orders. The study of mammals is called mammalogy. The largest orders of mammals, by number of species, are the rodents, bats, and eulipotyphlans (including hedgehogs, Mole (animal), moles and shrews). The next three are the primates (including humans, monkeys and lemurs), the Artiodactyl, even-toed ungulates (including pigs, camels, and whales), and the Carnivora (including Felidae, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salamandra Atra
The alpine salamander (''Salamandra atra'') is a black salamander that can be found in the Alps, and through the mountainous range in Europe. It is a member of the genus ''Salamandra''. Their species name, ''atra'', may be derived from the Latin ''ater'', meaning dull black. The salamanders' coloration has evolved over time, as some species are completely monochrome black and others have yellow spotting and marks. Their life expectancy is at least 10 years. There are four subspecies of the alpine salamander, with varied distribution and physical coloration. Unlike other salamanders, whose larvae are developed in water, the alpine salamander and its subspecies are a fully terrestrial species in life and gestation. They give birth to live young. Alpine salamanders produce toxic compounds from their skin. These compounds may protect them from both predator and microbial threats. Description Alpine salamanders are often small in size, and dark brown or black. Members of the subspec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Intra-uterine Cannibalism
Cannibalism is the act of consuming another individual of the same species as food. Cannibalism is a common ecological interaction in the animal kingdom and has been recorded in more than 1,500 species. Human cannibalism is also well documented, both in ancient and in recent times. The rate of cannibalism increases in nutritionally poor environments as individuals turn to members of their own species as an additional food source.Elgar, M.A. & Crespi, B.J. (1992) ''Cannibalism: ecology and evolution among diverse taxa'', Oxford University Press, Oxford ngland New York. Cannibalism regulates population numbers, whereby resources such as food, shelter and territory become more readily available with the decrease of potential competition. Although it may benefit the individual, it has been shown that the presence of cannibalism decreases the expected survival rate of the whole population and increases the risk of consuming a relative. Other negative effects may include the increa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adelphophagy
Cannibalism is the act of consuming another individual of the same species as food. Cannibalism is a common ecology, ecological interaction in the animal kingdom and has been recorded in more than 1,500 species. Human cannibalism is also well documented, both in ancient and in recent times. The rate of cannibalism increases in nutritionally poor environments as individuals turn to members of their own species as an additional food source.Elgar, M.A. & Crespi, B.J. (1992) ''Cannibalism: ecology and evolution among diverse taxa'', Oxford University Press, Oxford [England]; New York. Cannibalism regulates population numbers, whereby resources such as food, shelter and territory become more readily available with the decrease of potential competition. Although it may benefit the individual, it has been shown that the presence of cannibalism decreases the expected survival rate of the whole population and increases the risk of consuming a relative. Other negative effects may include ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oophagy
Oophagy ( ) or ovophagy, literally "egg eating", is the practice of embryos feeding on eggs produced by the ovary while still inside the mother's uterus. The word oophagy is formed from the classical Greek (, "egg") and classical Greek (, "to eat"). In contrast, adelphophagy is the cannibalism of a multi-celled embryo. Oophagy is thought to occur in all sharks in the order Lamniformes and has been recorded in the bigeye thresher (''Alopias superciliosus''), the pelagic thresher (''A. pelagicus''), the shortfin mako (''Isurus oxyrinchus'') and the porbeagle (''Lamna nasus'') among others. It also occurs in the tawny nurse shark (''Nebrius ferrugineus''), and in the family Pseudotriakidae. This practice may lead to larger embryos or prepare the embryo for a predatory lifestyle. There are variations in the extent of oophagy among the different shark species. The grey nurse shark (''Carcharias taurus'') practices intrauterine cannibalism, the first developed embryo consum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastric-brooding Frog
''Rheobatrachus'', whose members are known as the gastric-brooding frogs or platypus frogs, is a genus of extinct ground-dwelling frogs native to Queensland Queensland ( , commonly abbreviated as Qld) is a States and territories of Australia, state in northeastern Australia, and is the second-largest and third-most populous state in Australia. It is bordered by the Northern Territory, South Austr ... in eastern Australia. The genus consisted of only two species, the southern and Rheobatrachus vitellinus, northern gastric-brooding frogs, both of which became extinct in the mid-1980s. The southern gastric brooding frog was last seen in 1983 and was declared extinct in 2006. The northern gastric brooding frog was last seen in 1987 and was declared extinct in 2015. The genus is unique because it contains the only two known frog species that Avian incubation, incubated the prejuvenile stages of their offspring in the stomach of the mother. The combined ranges of the gastric-br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Darwin's Frog
Darwin's frog (''Rhinoderma darwinii''), also called the Southern Darwin's frog, is a species of frog of the family Rhinodermatidae. It was discovered by Charles Darwin during his voyage on HMS ''Beagle''. on a trip to Chile. In 1841, French zoologist André Marie Constant Duméril and his assistant Gabriel Bibron described and named Darwin's frog. The diet of ''R. darwinii'' consists mostly of herbivore invertebrates. ''R. darwinii'' is currently classified as an endangered species by the International Union for Conservation of Nature. Darwin's frog has an unusual method of brooding, in which the male will facilitate development of its tadpoles inside its vocal sac. This male brooding may make Darwin's frog unique among extant frog species, as the only other frog that has this behavior is the ''R. rufum'' (northern Darwin's frog), which has been presumed extinct since 1981. Characteristics Size Darwin's frog is a small species with a snout–to–vent length of . The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
