Humans Evolving From Mesoamerica?

What if humans evolved from Mesoamerica? Wow according to Diamond that would have affected so many things, for example, he mentions in page 159 the the major five domestication mammals (cows, sheep, goat, pig, and horse). Well these important mammal were not necessary found in Mesoamerica. He does mention the African Elephant but as you might have read form the reading, the African Elephant was captured and tamed but could not be domesticated, so both Africa and Mesoamerica had issues with animal domestication. With that being said, I believe the definition of a domesticated animal is: “...defined as animal selectively bred in captivity and thereby modified from its wild ancestors, for use by humans who control the animal's breeding and food supply.” (159).
Mesoamerica, I believe, would have been a harder place to start human evolution. Why? Honestly well Mesoamerica didn't have much large animals that could provide much of anything and the animals that were available were small or too hard to capture. Also Diamond, mentions how many animals change in size through out evolution. Yes they change size but they didn't get bigger in Mesoamerica in fact they got smaller in size that wouldn't have help us either.
Also in Mesoamerica, the animals were not use to humans, thus making them not aware to avoid the enemies, humans. The very few animals that were available in the island were being taken advantage of. Since the evolution of animals and humans would have been similar then I believe animal domestication would have taken longer to acquire. What do you guys think?