Question

Many very distantly related species of birds (e.g., penguins, ostriches, flightless ducks, and rails) share the trait of flightlessness even though their ancient common ancestors were able to fly. This independent evolution of flightlessness in many distantly related taxa exemplifies what type(s) of evolutionary/phylogenetic patterns?(A) Convergent evolution(B) Evolutionary reversal(C) A homoplastic trait(D) A synapomorphic trait(E) a, b, and c

Answer 1

Answer:

(E) a,b, and c

Explanation:

Flightlessness birds are distant, so this feature appeared different times in the phylogenic tree of the birds. This means, that this trait is not synapomorphic.  It is a result of convergent evolution in these species (penguins, ostriches, flightless ducks, and rails), probably as a consequence of similar environmental pressures or advantages. Also, it is a homoplasic trait because this feature has not a recent common ancestor to these species. Finally, it is an evolutionary reversal too because it is a trait that bird's ancestors had, but not the most immediate ancestor of these birds.