British scientists from the University of Reading have found a possible reason why individuals of certain animal species are decreasing in size over time. The study was published in the scientific journal magazine Communication Biology (CommsBio).
Experts used computer models to study evolutionary processes. They concluded that the size of animals over time depends on two key ecological factors: interspecific competition for resources and the risk of extinction from the environment.
“Just as we try to adapt to hot or cold weather depending on where we live, our research shows that the size of animals can increase or decrease over time.
Where there is less direct competition, individuals tend to increase in size. This occurs despite the fact that large size and small numbers can make animals more vulnerable to extinction. For example, this happened in dinosaurs,” said Dr. Shovondal Roy.
The research team discovered that some animal species contradict what is known as Cope’s rule, discovered by 19th-century paleontologist Edward Cope. The rule is that animals gradually increase in size as they evolve. For example, the ancestors of modern horses were no larger than the average dog, but over millions of years they evolved into large and powerful creatures.
The new analysis shows that for some species, the process goes in the opposite direction. These include certain types of bony fish, island-dwelling lizards, cryptonecked turtles, and extinct horses that lived in Alaska during the Pleistocene.
happened before knownIt was observed that some plants began to develop towards self-pollination.