The diagram illustrates the evolution of the horse over a 40-million-year period.
Overall, horses have gone through three main stages of physical development. Moreover, the foot structures have evolved from spread-out toes to a single hoof.
40 million years ago, the ancestor of the horse called Eohippus had a dog-sized body with some very primitive features such as a hairless back. After 10 million years, there was a noticeable development in the appearance of the horse. Particularly the Mesohippus was much bigger than Eohippus, with short hair and longer face. The horse went through the same evolution 5 million years later, when it was called Merychippus. Finally, after the period of 40 millions years, the modern horse has been significantly advanced. Compared to its ancestor, modern horses have bigger legs, longer hair as well as longer face.
A remarkable factor is that the foot structure of the horse has changed significantly after 40 million years. The Eohippus had short limbs with four toes spreaded out. When predators started to appear, the toes of Mesohippus and Merychippus were only three and one of which was longest to create a symmetrical structure that facilitated its running ability. Finally, spread-out toes were completely replaced by a single hoof
The diagram illustrates the evolution of the
horse
over a 40-million-year period.
Overall
,
horses
have gone through three main stages of physical development.
Moreover
, the foot structures have evolved from spread-out toes to a single hoof.
40
million
years ago, the ancestor of the
horse
called
Eohippus
had a dog-sized body with
some
very
primitive features such as a hairless back. After 10
million
years, there was a noticeable development in the appearance of the
horse
.
Particularly
the
Mesohippus
was much bigger than
Eohippus
, with short hair and longer face. The
horse
went through the same evolution 5
million
years later, when it
was called
Merychippus
.
Finally
, after the period of 40
millions
years, the modern
horse
has been
significantly
advanced. Compared to its ancestor, modern
horses
have bigger legs, longer hair
as well
as longer face.
A remarkable factor is that the foot structure of the
horse
has
changed
significantly
after 40
million
years. The
Eohippus
had short limbs with four toes
spreaded
out. When predators
started
to appear, the toes of
Mesohippus
and
Merychippus
were
only
three and one of which was longest to create a symmetrical structure that facilitated its running ability.
Finally
, spread-out toes were completely replaced by a single hoof