Question

Using various resources such as your school Library or the internal and discussions with your teacher. trace the evolutionary stages of any one animal, say horse.

Answer 1

"The development of horse began with Eohippus during the Eocene period. It included the accompanying developmental stages.

(I) A gradual increment in body estimate

(ii) Elongation of head and neck district

(iii) Increase in the length of appendages and feet

(iv) Gradual decrease of sidelong digits

(v) Enlargement of third practical toe

(vi) Strengthening of the back

(vii) Development of mind and tactile organs

(viii) Increase in the unpredictability of teeth for benefiting from grass

The evolution of the horse took place in the following order:

(I) Eohippus: It had a short head and neck. It had four practical toes and a brace of 1 and 5 on every rear appendage and support of 1 and 3 in every forelimb. The molars were short delegated that were adjusted for pounding the plant diet.

(ii) Mesohippus: It was marginally taller than Eohippus. It had three toes on each foot.

(iii) Merychippus It had the measure of around 100 cm. Despite the fact that regardless it had three toes in each foot, however, it could keep running on one toe. The side toe did not contact the ground. The molars were adjusted for biting the grass.

(iv) Pliohippus: It looked like the cutting edge horse and was around 108 cm tall. It had a solitary useful toe with a brace of second and fourth in every appendage.

(v) Equus: Pliohippus offered to ascend to Equus or the cutting edge horse with one toe in each foot. They have incisors for cutting grass and molars for pounding nourishment. "

Answer 2

Answer:

The evolution of horse started with Eohippus during Eocene period.

It involved the following evolutionary stages.

(i) Gradual increase in body size

(ii) Elongation of head and neck region

(iii) Increase in the length of limbs and feet

(iv) Gradual reduction of lateral digits

(v) Enlargement of third functional toe

(vi) Strengthening of the back

(vii) Development of brain and sensory organs

(viii) Increase in the complexity of teeth for feeding on grass

Explanation:

(i) Eohippus

It had a short head and neck. It had four functional toes and a splint of 1 and 5 on each hind limb and a splint of 1 and 3 in each forelimb.

The molars were short crowned that were adapted for grinding the plant diet.

(ii) Mesohippus

• It was slightly taller than Eohippus.
• It had three toes in each foot.

(iii) Merychippus

• It had the size of approximately 100 cm.
• Although it still had three toes in each foot, but it could run on one toe.
• The side toe did not touch the ground. The molars were adapted for chewing the grass.

(iv) Pliohippus

• It resembled the modern horse and was around 108 cm tall.
• It had a single functional toe with splint of 2nd and 4th in each limb.

(v) Equus

• Pliohippus gave rise to Equus or the modern horse with one toe in each foot.
• They have incisors for cutting grass and molars for grinding food.