Question

Judging by the nature of modern humans, chimpanzees, and bonobos, which of these traits did the last common ancestor of all three probably NOT show?

1) some form of culture

2) tool use to get and process food

3) a broad diet including plenty of fruit

4) strictly heterosexual mating patterns

5) some degree of hunting

Answer 1

Based on the sexual behaviors of bonobos and the opportunistic mating patterns of chimpanzees, strictly heterosexual mating patterns were likely not a trait of the last common ancestor of humans, chimpanzees, and bonobos.

Step-by-step explanation:

Traits of the Last Common Ancestor

When we examine the behaviors of modern humans, chimpanzees, and bonobos, we can deduce certain traits of their last common ancestor. Considering the diverse sexual behaviors of bonobos, which include same-sex interactions, and the less varied but still opportunistic mating patterns of chimpanzees, it is very likely that strictly heterosexual mating patterns were not a characteristic of the last common ancestor.

The fact that both humans and chimpanzees display some form of culture, use tools to obtain and process food, have a broad diet that includes fruit, and engage in some degree of hunting suggests that these traits were present in the last common ancestor. Hence, choice (4), which refers to strictly heterosexual mating patterns, would be the trait the last common ancestor probably did not show, based on the more flexible sexual behaviors observed in bonobos and the presence of non-heterosexual interactions in human societies.