The diagram shows how the horse evolved through time, with particular emphasis on its foot structure

The given diagrams illustrate the evolution of the horse with particular emphasis on the changing of its foot structure over a course of 40 million years. Overall, this development took 40 megaannum and had four stages in total. As the mammal gets more prominent in size and longer limbs, the toes disappear, eventually turned into a hoof. The Eohippus, which existed around 40 million years ago, was merely one-third of a modern one in size. All four legs and the tail were relatively short, and, on each sole, there were four toes. Approximately 10 million years later, the Eohippus became the Mesohippus, which was slightly larger and taller in stature and started to have a rudimentary form of the mane. The foot lost one toe, and the middle toe enlarged to create a symmetrical structure. Over the next 15 million years, Mesohippus developed into Mcrychippus that had a longer and bigger middle toe and also a stronger body structure. Simultaneously, it was almost identical in shape to the modern horse. Finally, after another 15 million years, the horse took its shape that we see today. It is taller, with lengthier limbs, a more defined tail and a clearer mane on the neck. The foot structure has all the toes reduced just to a single hoof.