- The pointy bone on top of the muzzle of the horse and the triangular shape of the head and the gap between front and rear teeth.
- Increase in the size of the skull; a shift from cusps to complex ridges on the grinding surface of the premolars and molars, elongation of the face and of the space between the incisors and cheek teeth, an anterior shift of the cheek teeth so they lie forward of the eye; a deep lower jaw bone.
- Fifty five million years ago, there was an animal the size of a small dog, called Hyracotherium (sometimes called Eohippus). Its front feet had four toes, and its back feet had three. Modern horse feet have a single hoof. We see the reduction and loss of the side toes and enlargement of the terminal phalanx (hood) elongation and enlargement of the central metapodial (the longest bone in the foot).
Parent Tip: Review the logic above to help your child master the concept of comparative embryology worksheet.
