* Evolutionary History: Horses evolved from small, multi-toed ancestors in the Eocene epoch, around 56 million years ago. Their early ancestors, like *Hyracotherium*, were not large or powerful, and didn't need horns for defense.
* Adaptive Advantages: Instead of developing horns, horses evolved other adaptations for survival:
* Speed: Their long legs and powerful muscles allow them to run quickly and escape predators.
* Herding Behavior: They live in social groups, providing safety in numbers.
* Strong Teeth: Their teeth are designed for grazing on grasses and other vegetation.
* No Need for Horns: Horses have never faced selective pressures that would favor the development of horns. They primarily rely on flight as their primary defense mechanism.
It's important to note: The evolution of horns in animals is often linked to specific ecological pressures and the need for defense or competition. While horns are present in many members of the horse family (like the extinct *Chalicotherium*), they are not present in modern horses because their evolutionary path took them in a different direction.