What is Cope's rule?

Cope's rule is one of several "biological rules" - biological trends found in samples across many plants and animals. Cope's rules state that the population lines tend to increase size during evolutionary time. There are many examples in evolutionary history - mammals increase after the demise of dinosaurs; reptiles increase after the disappearance of therapyids; amphibians increase in size after they reached the ground; All animals increase the size of the Cambrian explosion 540 million years ago ... and so on.

The larger size gives evolutionary advantages to individuals and species for many reasons, the most superficial is that a larger animal is harder to kill and can kill or defend themselves more easily. In fact, the larger size may be so evolutionary that the only brakes on Cope's rule are that the trunks composed of larger individuals are likely to disappear at the time of the problem (mainly because there, they have larger metabolic requirements than small). But there are other OMsEzive factors - for example, biomechanics - a bird that weighs too much cannot fly.

Cope's rule has been transferred to extreme animals such as whales that developed from land animals of wolves, and disappeared sauropods, dinosaurs who approached 200 feet (60 m). There are many other examples, especially due to mass extinction, where all larger animals are deleted. Some scientists have suggested that Cope's rule could be an artifact due to the fact that larger bones were easier to spoil, but the phenomenon seems to be robust enough that this selection effect will not significantly reduce it.

Cope's rule developed the strongest at the age of dinosaurs, when the average earthly vertebrates were much greater than those typical today. It can have something to do with the climate because the world was a much warmer place to live while today is a dirtyED extended ice age, with glacier maximum, which covers a large part of the northern hemisphere and all Antarctices in ice caps. This reduces the total amount of food available and causes what was once fresh forests into cold grass stands. In this environment, however, the size can still be an advantage because it leads to heat. This can be seen in the development of woolen mammoth.