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Paedomorphosis
Neoteny (), also called juvenilization,Montagu, A. (1989). Growing Young. Bergin & Garvey: CT. is the delaying or slowing of the Physiology, physiological, or Somatic (biology), somatic, development of an organism, typically an animal. Neoteny in humans, Neoteny in modern humans is more significant than in other primates. In progenesis or paedogenesis, sexual development is accelerated. Both neoteny and progenesis result in paedomorphism (as having the form typical of children) or paedomorphosis (changing towards forms typical of children), a type of heterochrony. It is the retention in adults of traits previously seen only in the young. Such retention is important in evolutionary biology, domestication, and evolutionary developmental biology. Some authors define paedomorphism as the retention of larval traits, as seen in salamanders.Schell, S. C. ''Handbook of Trematodes of North America North of Mexico'', 1985, pg. 22 History and etymology Julius Kollmann created the term ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heterochrony
In evolutionary developmental biology, heterochrony is any genetically controlled difference in the timing, rate, or duration of a Developmental biology, developmental process in an organism compared to its ancestors or other organisms. This leads to changes in the size, shape, characteristics and even presence of certain Organ (biology), organs and features. It is contrasted with heterotopy, a change in spatial positioning of some process in the embryo, which can also create Morphology (biology), morphological innovation. Heterochrony can be divided into intraspecific heterochrony, variation within a species, and interspecific heterochrony, phylogenetic variation, i.e. variation of a descendant species with respect to an ancestral species. These changes all affect the start, end, rate or time span of a particular developmental process. The concept of heterochrony was introduced by Ernst Haeckel in 1875 and given its modern sense by Gavin de Beer in 1930. History The conc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neoteny In Humans
Neoteny is the retention of juvenile traits well into adulthood. In humans, this trend is greatly amplified, especially when compared to non-human primates. Neotenic features of the head include the globular skull; (page 134), cited by:"In humans, neoteny is manifested in the resemblance of many physiological features of a human to a late-stage foetal chimpanzee. These foetal characteristics include hair on the head, a globular skull, ear shape, vertical plane face, absence of penal bone (baculum) in foetal male chimpanzees, the vagina pointing forward in foetal ape, the presence of hymen in neonate ape, and the structure of the foot. 'These and many other features', Bednarik says, 'define the anatomical relationship between ape and man as the latter's neoteny'". thinness of skull bones; the reduction of the brow ridge; the large brain; the flattened and broadened face; the hairless face; hair on (top of) the head; larger eyes; ear shape; small nose; small teeth; and the small max ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amphibians
Amphibians are ectothermic, anamniote, anamniotic, tetrapod, four-limbed vertebrate animals that constitute the class (biology), class Amphibia. In its broadest sense, it is a paraphyletic group encompassing all Tetrapod, tetrapods, but excluding the amniotes (tetrapods with an amniotic membrane, such as modern reptiles, birds and mammals). All extant taxon, extant (living) amphibians belong to the monophyletic subclass (biology), subclass Lissamphibia, with three living order (biology), orders: Anura (frogs and toads), Urodela (salamanders), and Gymnophiona (caecilians). Evolved to be mostly semiaquatic, amphibians have adapted to inhabit a wide variety of habitats, with most species living in freshwater ecosystem, freshwater, wetland or terrestrial ecosystems (such as riparian woodland, fossorial and even arboreal habitats). Their biological life cycle, life cycle typically starts out as aquatic animal, aquatic larvae with gills known as tadpoles, but some species have devel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Salamanders
Salamanders are a group of amphibians typically characterized by their lizard-like appearance, with slender bodies, blunt snouts, short limbs projecting at right angles to the body, and the presence of a tail in both larvae and adults. All ten extant salamander families are grouped together under the order (biology), order Urodela, the sole surviving order from the group Caudata. ''Urodela'' is a scientific Latin term based on the Ancient Greek : ourà dēlē "conspicuous tail". ''Caudata'' is the Latin for "tailed ones", from : "tail". Salamander diversity is highest in eastern North America, especially in the Appalachian Mountains; most species are found in the Holarctic realm, with some species present in the Neotropical realm. Salamanders never have more than four toes on their front legs and five on their rear legs, but some species have fewer digits and others lack hind limbs. Their permeable skin usually makes them reliant on habitats in or near water or other cool, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolutionary Developmental Biology
Evolutionary developmental biology, informally known as evo-devo, is a field of biological research that compares the developmental biology, developmental processes of different organisms to infer how developmental processes evolution, evolved. The field grew from 19th-century beginnings, where embryology faced a mystery: zoology, zoologists did not know how embryogenesis, embryonic development was controlled at the molecular level. Charles Darwin noted that having similar embryos implied common ancestry, but little progress was made until the 1970s. Then, recombinant DNA technology at last brought embryology together with molecular genetics. A key early discovery was that of homeotic genes that regulate development in a wide range of eukaryotes. The field is composed of multiple core evolutionary concepts. One is deep homology, the finding that dissimilar organs such as the eyes of insects, vertebrates and cephalopod molluscs, long thought to have evolved separately, are contr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ontogeny And Phylogeny
''Ontogeny and Phylogeny'' is a 1977 book on evolution by Stephen Jay Gould, in which he explores the relationship between embryonic development (ontogeny) and biological evolution (phylogeny). Unlike his many popular books of essays, it was a technical book, and over the following decades it was influential in stimulating research into heterochrony (changes in the timing of embryonic development), which had been neglected since Ernst Haeckel's theory that ontogeny recapitulates phylogeny had been largely discredited. This helped to create the field of evolutionary developmental biology. Context ''Ontogeny and Phylogeny'' is Stephen Jay Gould's first technical book. He wrote that Ernst Mayr had suggested in passing that he write a book on development. Gould stated he "only began it as a practice run to learn the style of lengthy exposition before embarking on my magnum opus about macroevolution." Also (paperback) This later work was published in 2002 as '' The Structure of Evol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Louis Bolk
Lodewijk 'Louis' Bolk (10 December 1866, Overschie – 17 June 1930, Amsterdam) was a Dutch anatomist who created the fetalization theory about the human body. It states that when a human being is born, it is still a fetus, as can be seen by its (proportionally) big head, lack of coordination, and helplessness. Furthermore, this " prematuration" is specifically human. Gavin de Beer and Stephen Jay Gould wrote about him and further developed this theory of neoteny in humans.) Also Jacques Lacan Jacques Marie Émile Lacan (, ; ; 13 April 1901 – 9 September 1981) was a French psychoanalyst and psychiatrist. Described as "the most controversial psycho-analyst since Sigmund Freud, Freud", Lacan gave The Seminars of Jacques Lacan, year ... took Bolk's fetalization theory into account in order to introduce his own thesis on the mirror stage. Bolk wrote in Origin of Racial Characteristics in Man, “White skin...started from an ancestor with a black skin, in whose offs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stephen Jay Gould
Stephen Jay Gould ( ; September 10, 1941 – May 20, 2002) was an American Paleontology, paleontologist, Evolutionary biology, evolutionary biologist, and History of science, historian of science. He was one of the most influential and widely read authors of popular science of his generation. Gould spent most of his career teaching at Harvard University and working at the American Museum of Natural History in New York. In 1996, Gould was hired as the Vincent Astor Visiting Research Professor of Biology at New York University, after which he divided his time teaching between there and Harvard. Gould's most significant contribution to evolutionary biology was the theory of punctuated equilibrium developed with Niles Eldredge in 1972.Eldredge, Niles, and S. J. Gould (1972)"Punctuated equilibria: an alternative to phyletic gradualism."In T.J.M. Schopf, ed., ''Models in Paleobiology''. San Francisco: Freeman, Cooper and Company, pp. 82–115. The theory proposes that most evolution is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lexico
''Lexico'' was a dictionary website that provided a collection of English and Spanish dictionaries produced by Oxford University Press (OUP), the publishing house of the University of Oxford. While the dictionary content on ''Lexico'' came from OUP, this website was operated by Dictionary.com, whose eponymous website hosts dictionaries by other publishers such as Random House. The website was closed and redirected to Dictionary.com on 26 August 2022. Before the Lexico site was launched, the ''Oxford Dictionary of English'' and ''New Oxford American Dictionary'' were hosted by OUP's own website ''Oxford Dictionaries Online'' (''ODO''), later known as ''Oxford Living Dictionaries''. The dictionaries' definitions have also appeared in Google Dictionary, Google definition search and the Dictionary (software), Dictionary application on macOS, among others, licensed through the Oxford Dictionaries API. History In the 2000s, OUP allowed access to content of the ''Compact Oxford Englis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adjective
An adjective (abbreviations, abbreviated ) is a word that describes or defines a noun or noun phrase. Its semantic role is to change information given by the noun. Traditionally, adjectives are considered one of the main part of speech, parts of speech of the English language, although historically they were classed together with Noun, nouns. Nowadays, certain words that usually had been classified as adjectives, including ''the'', ''this'', ''my'', etc., typically are classed separately, as Determiner (class), determiners. Examples: * That's a ''funny'' idea. (Prepositive attributive) * That idea is ''funny''. (Predicate (grammar), Predicative) * * The ''good'', the ''bad'', and the ''funny''. (Substantive adjective, Substantive) * Clara Oswald, completely ''fictional'', died three times. (Apposition, Appositive) Etymology ''Adjective'' comes from Latin ', a calque of (whence also English ''epithet''). In the grammatical tradition of Latin and Greek, because adjectives were I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
