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Pedomorphosis - Wikipedia, the free encyclopedia In developmental biology, paedomorphosis or juvenification is a phylogenetic change in which the adults of a species retain traits previously seen only in juveniles. Paedomorphosis is common in many animal species domesticated by humans, including dogs, chickens, pigs and cattle. Paedomorphosis is believed by some to be what caused the beginning of the phylum Chordata. en.wikipedia.org /wiki/Paedomorphosis   (261 words)

Abstract: Cahiers d'Ethologie 21 (2003): 327 pages Paedomorphosis occurs in aquatic habitats where total drying can occur, and where the maintenance of facultative paedomorphosis is maintained by metamorphs that have paedomorphic genes but do not (permanently) express them. Facultative paedomorphosis in the Alpine newt allows populations to cope with environmental variability, and is adaptive in allowing precocious maturation or a larger use of resources in spatially heterogeneous environments. Facultative paedomorphosis is widespread in newts and salamanders, where it is defined as larvae maturing without undergoing metamorphosis and thus retaining their gills at the adult stage. www.etho.ulg.ac.be /abstract/MD-2003-CE-EN.html   (1508 words)

Phenotypic variation in metamorphosis and paedomorphosis in the salamander Ambystoma talpoideum. Phenotypic variation in metamorphosis and paedomorphosis in the salamander Ambystoma talpoideum. Phenotypic variation in metamorphosis and paedomorphosis in the salamander Ambystoma talpoideum was examined to determine its environmental or genetic basis. The water level in the drying treatment was lowered during the last 10 wk of the experimental period with no apparent differences in water chemistry parameters between treatments and only a slight change in water temperature during the last 2 wk. www.uga.edu /srel/Reprint/0972.htm   (278 words)

Public Anthropology Paedomorphosis is a very generalized way of understanding why we act and interact in the way we do, which has been done for thousands of years but only in different contexts of kinship groups, tribes, castes, or clans. Paedomorphosis is highly intertwined within the effects of evolution, which without them (such as bipedalism, placement of foramen magnum, longer maturation period, etc), the effects of paedomorphosis would not influence our learning abilities. What paedomorphosis did for human society was to allow humans another opportunity to overcome their genetic endowment and embrace the new genetic knowledge of language and the ever-increasing knowledge of the universe around us. www.publicanthropology.org /Archive/Ca1971.htm   (8769 words)

Anders Galatius-Jørgensen   (Site not responding. Last check: 2007-11-01) Heterochronic development may manifest itself as paedomorphosis (retainment of juvenile characters in the adult form) which is a widespread phenomenon in animals. Paedomorphosis can be the result of different processes; the classical distinction is between progenesis (early onset of sexual maturity) and neoteny (retardation of somatic development relative to sexual development). Progenetic paedomorphosis is of obvious interest to studies of life history evolution since it may allow shorter generation times. www.bi.ku.dk /students/stud-PHD-details.asp?ID=425   (512 words)

ESA 2005   (Site not responding. Last check: 2007-11-01) Paedomorphosis in Ambystoma talpoideum: effects of initial body size variation and density. One such polyphenism is facultative paedomorphosis, in which individuals either metamorphose into a terrestrial, metamorphic adult or retain a larval morphology to become a sexually mature paedomorphic adult. It is hypothesized that density and initial body size variation within populations are instrumental in cueing metamorphosis or paedomorphosis in salamanders, yet few studies have adequately addressed these questions using long-term experiments. abstracts.co.allenpress.com /pweb/esa2005/document?ID=51111   (301 words)

Heterochrony "The cranial paedomorphosis and neoteny in P. paniscus may be related to reduced sexual dimorphism in morphology and behavior since reduction or truncation of a structure's growth yields reduced sexual dimorphism. Nevertheless, the modification of skull structure, and particularly the central position of the foragmen magnum, was essential if the utmost advantage was to result from bipedalism, since this allowed the head to be easily balanced in the upright position. Paedomorphosis is the essential link at the interface between the structure of man and his unique behavior." (Crombie, Donald L. (1971) The group system of man and paedomorphosis. www.neoteny.org /a/heterochrony2.html   (7990 words)

Steve Moxon reviews The Eternal Child: An Explosive New Theory of Human Origins and Behaviour by Clive Bromhall The role of paedomorphosis in the development of a host of physical attributes is made comprehensively, and the neglected role of big cat predation in human evolution is usefully highlighted. The idea that neoteny (also called paedomorphosis) has had an impact on human evolution is hardly new, but most people will be taken aback at how pervasive it seems to have been - at least in Bromhall's account. Bromhall seems not to realise that this would render his paedomorphosis theory redundant, and that with either exaptation or paedomorphosis his psychoanalytic interpretation is misplaced. human-nature.com /nibbs/03/moxon.html   (1581 words)

Growth and foraging consequences of facultative paedomorphosis in the tiger salamander, Ambystoma tigrinum nebolosum Facultative paedomorphosis in salamanders occurs when larvae respond to varying environmental conditions by either metamorphosing into terrestrial metamorphic adults or retaining their larval morphology to become sexually mature paedomorphic adults. Thus, facultative paedomorphosis may be maintained in part by variable, environmentally-specific fitness payoffs to each morph. Growth and foraging consequences of facultative paedomorphosis in the tiger salamander, Ambystoma tigrinum nebolosum. www.uga.edu /srel/Reprint/2099.htm   (446 words)

Abstract: Journal of Biogeography 28 (2001): 1271-1280 Aim - Paedomorphosis is an evolutionary change in which larval structures are retained in adult animals. In newts and salamanders, this heterochronic process is widely represented and concerns the retention of gill slits. These results support models predicting paedomorphosis in varied environments, but require complementary investigations on the costs and benefits of the alternative ontogenetic pathways. www.etho.ulg.ac.be /abstract/MD-2001-JB.html   (269 words)

244 HETEROCHRONY AND PAEDOMORPHOSIS   (Site not responding. Last check: 2007-11-01) Here we had true paedomorphosis since the rate of phyletic size increase lagged far behind the value of 5. They must be equal for evolution to proceed in geometric similarity.) This example illustrates two important points: First, paedomorphosis and recapitulation are general results that depend upon a criterion of standardization and bear no ineluctable relation to any heterochronic process. The retardation that often leads to paedomorphosis can yield an equality of shape at corresponding developmental stages of ancestor and descendant. www.sjgarchive.org /library/text/ontogeny/p0244.htm   (401 words)

Howard Whiteman - Research This dimorphism, called facultative paedomorphosis, is environmentally induced because environmental conditions experienced as a larva influence whether an individual becomes one morph or the other. Because the expression of facultative paedomorphosis is environmentally induced, yet genetically based (and thus subject to natural selection) and because the two morphs interbreed (and thus are potentially influenced by sexual selection), facultative paedomorphosis provides an unique system in which to test the relative strength of these two evolutionary forces. Facultative paedomorphosis in an Indiana population of the tiger salamanders, Ambystoma tigrinum tigrinum. campus.murraystate.edu /academic/faculty/Howard.Whiteman/research.shtml   (2308 words)

The Genetics of Metamorphosis If this theory is correct, then their are two alternate alleles at a major locus primarily responsible for determining the expression of metamorphosis or paedomorphosis. The evolution of paedomorphosis from an ancestral obligate metamorph may have been selected for as the result of ecological opportunity. Phylogenetic studies indicate that paedomorphosis has evolved independently in several ambystomid salamanders that inhabit waters devoid of aquatic predators (Voss and Shaffer 1997). www.bio.davidson.edu /courses/anphys/2000/Richardson/Genetics.htm   (299 words)

Neoteny - Wikipedia, the free encyclopedia It is also theorized that the phylum Chordata first originated as a result of paedomorphism occurring in a highly primitive animal such as a sponge or coral. Neoteny and progenesis are both mechanisms that result in paedomorphosis. Comparatively, progenesis halts development of the organism before achieving the adult maturity experienced by its ancestors. en.wikipedia.org /wiki/Neoteny   (645 words)

Metamorphosis vs Neoteny This was clearly shown by Ashley-Ross (1994), in her study on this subject. Other terms such as paedogenesis and paedomorphosis have been applied and constantly redefined with the addition of new terms (progenesis, parthenopaedogenesis) only to hamper effective communication in this area (Duellman and Trueb, 1986). Whiteman, Howard H. Evolution of Facultative Paedomorphosis in Salmanders. darkwing.uoregon.edu /~titus/herp_old/neoteny.htm   (1727 words)

Shapes of Time (Kenneth McNamara) - book review These can each take three forms: paedomorphosis can be the result of progenesis (finishing early), neoteny (slower growth rate), and postdisplacement (starting late), while peramorphosis can result from predisplacement (starting early), acceleration (greater growth rate), and hypermorphosis (finishing late). This is enough background for the higher level (zoological and ecological and paleontological) survey that follows, but may be frustratingly slender for those after more, after a better understanding of the developmental biology behind heterochrony. McNamara begins his tour of heterochrony with dog varieties — even looking at paedomorphosis in depictions of Snoopy in Peanuts cartoons — and examples from insects and salamanders. dannyreviews.com /h/Shapes_Time.html   (688 words)

376 HETEROCHRONY AND PAEDOMORPHOSIS   (Site not responding. Last check: 2007-11-01) occur.* Given the fact of this matrix, it would be surprising indeed if paedomorphosis had not played a dominant role in human evolution (Table 9). Although I have tried to establish general retardation as an enabling criterion for massive human paedomorphosis, an assessment of our neoteny still requires a discussion of morphological features. General retardation of this sort entails extensive paedomorphosis as an almost ineluctable consequence. www.sjgarchive.org /library/text/ontogeny/p0376.htm   (370 words)

e-Prints Soton - Paedomorphosis affects agonistic visual signals of domestic dogs   (Site not responding. Last check: 2007-11-01) Goodwin, Deborah, Bradshaw, John W.S. and Wickens, Stephen M. Paedomorphosis affects agonistic visual signals of domestic dogs. Many of the structural modifications of modern breeds of domestic dog,Canis familiariscan be explained by changes in the rate of development, during domestication from the wolf,C. lupusThese changes have been dominated by paedomorphosis, or underdevelopment, so that the adult passes through fewer growth stages and resembles a juvenile stage of its ancestor. In this paper the effects of these processes on the signalling ability of 10 breeds selected for their degree of physical dissimilarity to the wolf are examined. eprints.soton.ac.uk /18255   (203 words)

Evolution of Salamander Life Cycles: A Major-Effect Quantitative Trait Locus Contributes to Discrete and Continuous ... that the evolution of paedomorphosis is associated with genetic 2.— Likelihood-ratio statistic (LRS) plot for association of paedomorphosis with genetic factors in the met QTL region. associated with delayed metamorphosis and expression of paedomorphosis. www.genetics.org /cgi/content/full/170/1/275   (3174 words)

Recent Publications   (Site not responding. Last check: 2007-11-01) Ward, D & Slotow, R. Paedomorphosis and shell-colour polymorphism of a desert landsnail. Environmentally-driven paedomorphosis, the retention of juvenile characteristics by adults, is an overlooked alternative to adaptive genetic hypotheses regarding shell colour in landsnails. Here we consider the consequences of differential variation in shell shape of different colout morphs, and conclude that shell-colour variation in this species is a consequence of paedomorphosis in brown individuals. www.nu.ac.za /sles/papers/papers.asp?id=62   (152 words)

Evolution - A-Z - Paedomorphosis   (Site not responding. Last check: 2007-11-01) Paedomorphosis has occurred when reproduction is seen in what was ancestrally a juvenile morphological stage. This can be the result of neoteny or progenesis. The Mexican axolotl opposite is a famous example of paedomorphosis, retaining in maturity the feathery gills that related species lose in infancy. www.blackwellpublishing.com /ridley/a-z/Paedomorphosis.asp   (99 words)

Paedomorphosis ( Re: BARYONYX' CLAWS )   (Site not responding. Last check: 2007-11-01) From the suboscine tapaculos to paleognathus ratites to gruiform island rails the sole factor that can be used to describe similiarity between the groups is their paedomorphic characters. The flat, sternum, the massive and disproportionate hindlimbs, the body proportions, the lowering the basal metabolic rate, and "furry" plumage can all be explained by paedomorphosis. Since most or all flightless birds have these characteristics, I find it safe to assume that paedomorphosis is the factor that makes birds flightless. dml.cmnh.org /1998Apr/msg00346.html   (182 words)

Search results for research title I study the ecology and ethology of newts and salamanders in natural populations, but also in the laboratory to test specific hypotheses. This heterochronic process is considered to play an important role in species evolution and optimal use of the environment. Denoël M. Paedomorphosis in the Alpine newt (Triturus alpestris): decoupling behavioral and morphological change. www.br.fgov.be /cgi-bin/BIODIV/research.pl?res_id=1498   (510 words)

v.ramos [IST]   (Site not responding. Last check: 2007-11-01) ABSTRACT: Neoteny, also spelled Paedomorphosis, can be defined in biological terms as the retention by an organism of juvenile or even larval traits into later life. In terms of evolutionary theory, the process of paedomorphosis suggests that larval stages and developmental phases of existing organisms may give rise, under certain circumstances, to wholly new organisms. Although the present work does not pretend to model or simulate the biological details of such a concept in any way, these ideas were incorporated by a rather simple abstract computational strategy, in order to allow (if possible) for faster convergence into simple non-memetic Genetic Algorithms, i.e. alfa.ist.utl.pt /~cvrm/staff/vramos/ref_35.html   (413 words)

Female Centered Proto-Culture and Promiscuous Social Structures: Matrilineal Studies Nevertheless, the modification of skull structure, and particularly the central position of the foramen magnum, was essential if the utmost advantage was to result from bipedalism, since this allowed the head to be easily balanced in the upright position. In this section include the bonobo female exagamy as tentatively characteristic of hominid and early anatomically correct human societies, supported by Red Queen assertions of stressed human females giving birth to more females suggesting they would be the sex that would travel to a new community. This "shuffling" of the developmental trajectories of various body regions may provide new adaptive morphological configurations with minimal genetic changes." (Shea, B.T. (1983) Paedomorphosis and neoteny in the pygmy chimpanzee. www.humanevolution.net /a/matrilineal.html   (9100 words)

391ManChXVIII.htm Terms to know: heterochrony, paedomorphosis, terminal addition, ontogeny, "ontogeny recapitulates phylogeny", von Baer's Law, regulatory gene, HOM/Hox gene. Which hypothesis (paedomorphosis or terminal addition) does this pattern support? Draw the appropriate phylogeny, including this outgroup, to support this hypothesis. www.utm.edu /departments/cens/biology/rirwin/391/391ManChXVIII.htm   (989 words)

Paedomorphosis and neoteny in the pygmy chimpanzee.   (Site not responding. Last check: 2007-11-01) The strongly paedomorphic skull form in the pygmy chimpanzee results from the heterochronic process of neoteny. This cranial paedomorphosis and neoteny in Pan paniscus may be related to reduced sexual dimorphism in morphology and behavior. The interspecific differences in form result from shifts in the rate and timing of similar patterns of development. www.arclab.org /medlineupdates/abstract_6623093.html   (62 words)

Find in a Library: Expression of a life cycle polymorphism facultative paedomorphosis in Amybstoma talpiodeum Find in a Library: Expression of a life cycle polymorphism facultative paedomorphosis in Amybstoma talpiodeum Expression of a life cycle polymorphism facultative paedomorphosis in Amybstoma talpiodeum WorldCat is provided by OCLC Online Computer Library Center, Inc. on behalf of its member libraries. worldcatlibraries.org /wcpa/ow/88eb6a3ea4c814fea19afeb4da09e526.html   (64 words)

selective paedomorphosis   (Site not responding. Last check: 2007-11-01) If Nature gets to pick and choose among available neotenic characters, why not admit the other usual evolutionary mechanisms as well? Prev by Date: Re: Paedomorphosis (Re: BARYONYX' CLAWS) Previous by thread: ah, just some old stuff, cladograms and like that. dml.cmnh.org /1998Apr/msg00442.html   (208 words)

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