The picture demonstrates the way horses has changed over an amount of time of 40 million years. There were four types of horses through this period which got their names depending on how they were built, in particular, their feet and size.
First of all, eohippus who set the beggining of all horses. This species appeared 40 million years ago, and can be known as owners of limbs with four distincted fingers and a little body-size. After 10 million years horses reached the next stage of the development called mesohippus. Their fingers grew together slightly. However, the lenght of it differed. Also, their size increased. In another 15 million years such creature as merychippus were discovered. This type’s fingers equalled and was almost the same. The size kept growing gradually. Afterwards, horses reached their current stage of evolution. Their limbs have reducted fingers and their size differs significantly from eohippus.
In conclusion, throughout 40 million years horses’ limbs and size have witnessed a great number of changes.
