The following numbered sets each represent a distinct group of organisms: (1)three toes per foot,feathers,cold-blooded,no finger adaptations
(2)three toes per foot,body hair,warm-blooded,opposable thumbs
(3)three toes per foot,feathers,warm-blooded,no finger adaptation
(4)three toes per foot,body hair,warm-blooded,no finger adaptations
Which of the following choices is the most likely to represent the order in which these groups would appear on an evolutionary tree,from oldest to youngest?

Question

Quizplus · Accepted Answer

Group 1 has characteristics of reptiles/birds, and group 2 has characteristics of mammals/primates. Therefore, we can infer that the split between these two groups (i.e. the common ancestor) occurred early on in evolutionary history. 
Group 3 has feathers, which are unique to birds, indicating that it evolved later than group 1. 
Group 4 has warm-bloodedness, which is a more advanced trait compared to cold-bloodedness, and also has no finger adaptations, indicating that it evolved after group 2. 
Therefore, the most likely order is 1,3,4,2, which matches with choice C.

The Following Numbered Sets Each Represent a Distinct Group of Organisms