What is paedomorphosis in zoology?
Paedomorphosis is an alternative process to metamorphosis in which adults retain larval traits at the adult stage. It is frequent in newts and salamanders, where larvae reach sexual maturity without losing their gills. However, in some populations, larvae overwinter in water, while remaining immature.
What is an example of paedomorphosis?
For example, great crested newt (Triturus cristatus), palmate newt (Lissotriton helveticus), alpine newt (Ichthyosaura alpestris) and southern banded newt (Omatotriton vittatus) all exhibit paedomorphosis, especially in the south of their range (Oromi et al., 2014).
What is paedomorphosis in evolution?
paedomorphosis The evolutionary process in which larval or juvenile features of an ancestral organism are displaced to the adult forms of its descendants. It can arise by neoteny or progenesis.
How does paedomorphosis occur?
Paedomorphosis has occurred when reproduction is seen in what was ancestrally a juvenile morphological stage. This can be the result of neoteny or progenesis. Pedomorphosis may have two important evolutionary effects: It may stop recapitulation that occurs during the development of the organism.
How many types of paedomorphosis are there?
There are two types of paedomorphosis found in urodeles. i. Obligatory Paedomorphosis: Some species of urodeles or larval stages always remain mature permanent larval stages.
What is the difference between paedomorphosis and Peramorphosis?
Classifying Heterochrony. Heterochrony can be separated into two different types: paedomorphosis (literally “child-shape”) and peramorphosis (literally “beyond-shape”).
What are benefits of paedomorphosis?
Facultative paedomorphosis allows individuals to cope with habitat variation, to take advantage of environmental heterogeneity in the presence of open niches, and to increase their fitness.
What is the difference between neoteny and paedomorphosis?
Paedomorphosis and neoteny represent two qualitatively different phenomena: neoteny is an adaptive modification of ontogeny, whereas paedomorphosis is its transformation in the course of evolution.
Do humans have paedomorphosis?
Neoteny is found in modern humans compared to other primates. In progenesis or paedogenesis, sexual development is accelerated. Both neoteny and progenesis result in paedomorphism or paedomorphosis, a type of heterochrony. It is the retention in adults of traits previously seen only in the young.
What is the difference between synapomorphy and Symplesiomorphy?
The main difference between synapomorphy and symplesiomorphy is that in synapomorphy, two or more taxa share a character with their recent common ancestor while, in symplesiomorphy, the character shared by the two or more taxa occurs in their earliest common ancestor.
What is paedomorphosis?
The paedomorphosis (Gk. pais, child; morphe, form) is the retention of ancestral juvenile characters in the late developmental stages of descendants. The affected individuals are called paedomorphic.
What is the difference between paedomorphosis and neoteny?
But Kardong, 2002 refers to Paedomorphosis as an individual which is larval in anatomy but it becomes sexually mature and neoteny is a special case of paedomorphosis where sexual maturity occurs but somatic development slows, allowing juvenile features to persist. Garstang proposes the term paedomorphosis in 1928.
How does paedomorphosis arise in chordates?
It can arise by neoteny or progenesis. Paedomorphosis is thought to have occurred in the evolution of higher chordates from free-swimming larval tunicates, in which metamorphosis was eventually lost and sexual development accelerated until larval forms were capable of breeding. Pick a style below, and copy the text for your bibliography.
What is pedomorphosis in animals?
Pedomorphosis is common in many animal species domesticated by humans, including dogs, chickens, pigs and cattle. It is believed to be a side-effect of the selective pressure of human-directed breeding for juvenile behavioral characteristics such as docility and cuteness. Pedomorphosis also occurs in termites and several species of cockroach.