Consider the recent phylogenetic tree of five different organisms.

Question

A phylogenetic tree is shown. The root of the tree is birds. The branches are crocodiles, bats, and insects.

Old classification systems based on physical characteristics would most likely disagree with the relationship between which two animals in the tree?
crocodiles and insects
bats and humans
birds and bats
humans and crocodiles

Answer 1

The old classification systems based on physical characteristics would most likely disagree with the relationship between bats and birds in the tree. This is because bats and birds are grouped together in a common branch, which is something that might have been unexpected based solely on physical characteristics. In the past, bats may have been separated into a different group due to their ability to fly and their physical similarities with rodents, despite their actual evolutionary relationship with birds.