* Selective Breeding is a Form of Genetic Engineering: While we might not have had the technology to directly alter DNA sequences, domestication involves carefully selecting animals with desirable traits to breed. This process, over many generations, fundamentally alters the genetics of the population. It's a form of "natural" genetic engineering.
* Domestication Requires Behavioral Changes: Horses, in their wild state, are not naturally docile or willing to be ridden. Domestication requires changes in temperament, social structure, and tolerance for human interaction. These changes are driven by genetic differences, which are likely influenced by selective breeding.
* The Role of Genetic Variation: Domesticated horses display a range of traits not found in wild horses. This variation implies that genetic mutations were introduced and then amplified through selective breeding. These mutations might have contributed to increased docility, tolerance for confinement, or even changes in coat color.
Therefore, it's plausible that, even without direct genetic engineering, the process of domestication itself involved significant genetic changes that would have been unlikely to occur naturally.
It's important to note:
* We don't have direct evidence of genetic engineering in the early stages of horse domestication. Our knowledge is based on comparisons between wild and domesticated horses.
* The precise genetic changes involved in horse domestication are still being studied.
In conclusion: While not in the modern sense of gene editing, the process of domestication itself acts as a form of genetic engineering. It's unlikely that horses would have become domesticated without significant genetic alterations, even if those changes were indirect.