The platypus.
What is it?
The platypus is a semi-aquatic mammal endemic to eastern Australia and the island of Tasmania.
The unusual appearance of this venomous, egg-laying mammal with a duck-like snout, beaver tail and otter paws surprised many naturalists, who have come to consider it false.
Until the early 20th century it has been hunted for its skin, but is currently protected throughout its range. It is not thought to be under immediate threat, since captive breeding programs have had quite limited success, but are a species vulnerable to the effects of pollution.
Description.
Well, it is usually a deep brown color on the back and sides of the head, body and upper legs; the ventral region is a silky blond or gray color. The body and the wide flat tail are covered with a thick coat that retains a layer of insulating air that keeps the animal warm. It has webbed feet and a large snout wide and flat, covered with soft skin and wet rubber-like appearance; These features are more similar to those found in a duck that to those found in any mammal known. The membrane that has between them fingers of them legs front is greater that the of them later and exceeds the end of them fingers to get greater surface of thrust, since is with them with which is displaces during the diving. When you scroll through land collapses the membrane back, leaving exposed their strong nails. The tail is similar to the of the Beaver, but to difference of this, that it employs to propel is, the Platypus only it uses to maneuver in the water; also uses the tail as warehouse of reserves of fat, an adaptation that also present animals as the devil of Tasmania.
But well, the goal of this blog is to answer the question: why do the Platypus have similar to the beaver tail? So... I think that it would be okay to analyze their evolution a little.
According to Wikipedia: "the fossil more old discovered of Platypus modern data of ago some 100 000 years, during the period Pleistocene. The extinct monotremes (Teinolophos and Steropodon) were closely related to the modern Platypus. A Steropodon fossilized was discovered in New Welsh of the South, consistent in a maxillary lower opal with three teeth molars (whereas the Platypus adult modern lacks of teeth). He was initially believed that the molars were tribosfenicos, but subsequent research suggested that, despite having three cusps, they evolved in a separate process. Because of the early divergence of the mammals terios and the small number of living species of monotremes, the Platypus is an important and frequent subject of study in the field of evolutionary biology. In 2004 researchers of the University national of Australia discovered that has ten chromosomes sexual, in contrast with those two (XY) of it most of them mammals (e.g., a male always will be XYXYXYXYXY). While given the XY designation of mammals, the sex chromosomes of the Platypus are more similar to the ZZ/ZW sex chromosomes of birds. Its genome also has genes both reptilian and mammal associated with fertilization of eggs. Since it lacks the SRY gene that determines sex in mammals, the Platypus sex determination process is not yet known. The study found that more than the 80% of their genes are common to them mammals of which is have sequenced them genes, and that the genome of the Platypus, as the animal in itself, is an amalgam of ancestors reptilian and characteristics derived of them mammals ".
Then, as is explained in the previous paragraph; the Platypus are a kind of mix of features of mammals ancestors... and current. And therefore to be beaver also a mammal, I guess esto to clarify the why have similar, but not equal tails.
Thanks for reading.
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