The diagram exemplifies the evolution of equine species over the 40 million period, with its three ancestral species, illustrated by the modern horse and a clear focus on the morphological changes of the foot.
Overall, all 4 species have a common trait of being quadrupedal, they have increased in size, evolved to have more hair on the tail and mane and having toes to a single hoof on each foot.
The Eohippus which lived 40 million years ago, had four short legs, this kind of animals had small torso and its tail was not easily to realize. While the Mesohippus and Merychippus, which were existed 30 and 15 million years ago, had elongated tails and simple form of the mane, the height of these two species were increased gradually, but the overall stature of them were unchanged. The modern horse have the most evident tail and mane, the height and the length of body are about three halves of its oldest shown ancestors.
The foot of Eohippus have four separated toes within phalanxes, while in the Mesohippus and Merychippus, the number reduced to three and the middle phalanx was enlarged, and starts to resemble a hoof. The modern horse’s foot has the fewest bony structures and the hoof has replaced toes.
The diagram exemplifies the evolution of equine species over the 40 million period, with its three ancestral species, illustrated by the modern horse and a
clear
focus on the morphological
changes
of the foot.
Overall
, all 4 species have a common trait of being quadrupedal, they have increased in size, evolved to have more hair on the
tail
and mane and having toes to a single hoof on each foot.
The
Eohippus
which
lived
40 million years ago, had four short legs, this kind of animals had
small
torso and its
tail
was not
easily
to realize. While the
Mesohippus
and
Merychippus
, which
were existed
30 and 15 million years ago, had elongated
tails
and simple form of the mane, the height of these two species
were increased
gradually
,
but
the
overall
stature of them
were unchanged
. The modern horse have the most evident
tail
and mane, the height and the length of body are about three halves of its oldest shown ancestors.
The foot of
Eohippus
have
four separated toes within phalanxes, while in the
Mesohippus
and
Merychippus
, the number
reduced
to three and the middle phalanx
was enlarged
, and
starts
to resemble a hoof.
The
modern horse’s foot has the fewest bony structures and the hoof has replaced toes.