Why the changes helped - They got taller so they could spot predators in the grass while grazing with their heads in the ground & they got rid of the toes because it added weight

Environmental Changes - Due to the climate forests changed into grasslands so the horses needed to adapt to the new food, environment, ect.

Function - The back legs were longer than the front legs to run away from predators, teeth to eat leaves, ect.

How it has changed - Over time the animal got bigger in height & the feet have been losing their toes

Function - Legs were able to move faster, teeth were able to sheer leaves,

How it changed - Over time it got a bigger brain & legs

Function - High-crowned cheek to graze, longs legs helped to escape predators

How it has changed - Got rid of the three toes for one which is the modern day horse's hoove

Function - Teeth for grazing, toes for running

How it changed - Two toes to a hove

Function - Eyes constantly adjusts the amount of light it lets in and focuses on objects near and far,

How it chnaged - Increase in size, reduction in the number of hooves, loss of the footpads, lengthening of the legs, fusion of the independent bones of the lower legs, elongation of the muzzle, increase in the size and complexity of the brain

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