There is an interesting principle in animal evolution: bigger does not always mean better. Large animals, such as mammoths and saber-toothed tigers, had advantages in hunting, but lost in other things.
Recent studies using computer modeling have shown that some species of fauna are decreasing in size over time due to intense competition and high risk of extinction.
In some cases, the so-called Cope’s rule, which states that animals tend to get bigger and bigger, is violated. In harsher conditions, populations can maintain their size for a long time or even decline.
The now proposed “regular inverse Cope’s rule” explains this tendency by saying that high competition forces animals to seek new ecological niches, but creatures always have a need to return to their original resources. This goal is easier to achieve by limiting themselves in size.
