Humans, mice and giraffes had seven vertebrae in their neck. What can scientist conclude from this observation? Would it be each animal independently evolved? This trait of vertebrae have seven vertebrae in their necks humans, mice and giraffes have the same number of bones these animals descended from a common ancestor.
Based on the observation that humans, mice, and giraffes all have seven vertebrae in their necks, scientists can conclude that these animals share a common ancestor. This trait of having seven neck vertebrae is likely inherited from a common ancestor and has been passed down through generations.
The fact that these animals independently evolved the same trait is highly unlikely because the probability of each species randomly acquiring the same number of vertebrae is low. Therefore, the most reasonable explanation is that their shared ancestry is responsible for this trait.