Question

Why do cows not have upper front teeth​

Answer 1

Answer:

Basically it's genetics, evolution, adaptation, what ever you want to call it. Most of these animals are primarily grazers, others browsers, and have used their tongues to grasp and pull in the fodder into their mouths. Their lower fronts shear off the foliage, and probably have proven much more useful for that than the fronts. Adaptation to such eating methods likely has reduced the need for the upper fronts, or more rather by natural selection those animals with reduced upper front teeth were better foragers (and better survivors) than those that have more pronounced frontal incisors. And so it progressed from there.

Explanation: