The evaluation of the horse Исполнитель

The diagram reveals the development of  a horse over a 40 million period.

40 million years ago, a horse was called as Eohippus. At this stage, it had four fingers in its small body like dogs. After 10 million years, it was called as Mesohippus.  There were some alterations in its body, especially in its foot form where last one finger lost and a middle finger became longer and thinner.  For the next fifteen million years, Mesohippus underwent few changes, turning into horse shape and having longer tail and fingers. In this phase, it was called Merychippus before turning into our modern horse. A modern horse is more beautiful with its well-shaped body, long tail and mane as well as its totally transformed foot structure from fingers into hoofs.

Overall, a horse has witnessed dramatic changes comprising 4 evolutions before having modern appearance.