Horse Diagram
Writing Task
You should spend about 20 minutes on this task.
The diagram below shows the evolution of the horse over a period of 40 million years, with particular emphasis on the development of the foot.
Summarise the information by selecting and reporting the main features, and make comparisons where relevant.
Write at least 150 words.
Sample Answer
The diagram illustrates the evolution of the horse over a period of 40 million years, focusing specifically on the changes in foot structure and overall body development.
Overall, horses have undergone a significant increase in size and a transformation of their feet, evolving from multiple slim toes to a single strong hoof, enabling greater support and mobility.
The earliest ancestor, the Eohippus (40 million years ago), had a small body and four distinct toes. This primitive structure evolved into the Mesohippus (30 million years ago), which was slightly larger and had three toes, with the central digit more prominent.
By 15 million years ago, the Merychippus appeared with a more developed physique and a much larger central toe, while the two side toes were reduced. In the modern era, the Equus represents the final stage: it has the largest body, a well-developed mane, and a single hoof, formed from the fusion of previous toes to support its greater weight.