When Charles Darwin first proposed the idea that all new species descend from an ancestor, he performed an exhaustive amount of research to provide as much evidence as possible. Today, the major pieces of evidence for this theory can be broken down into the fossil record, embryology, comparative anatomy, and molecular biology.
This is a series of skulls and front leg fossils of organisms believed to be ancestors of the modern-day horse.
1. Give two similarities between each of the skulls that might lead to the conclusion that these are all related species.
2. What is the biggest change in skull anatomy that occurred from the dawn horse to the modern horse?
3. What is the biggest change in leg anatomy that occurred from the dawn horse to the modern horse?