Question

The fossil record indicates that the earliest prehistoric birds emerged during the Jurassic period. All modern birds have evolved from these early, reptile-like birds.

Based on their common ancestry, which of the following is most likely true about modern birds?
A.
Modern bird species cannot undergo evolutionary changes.
B.
Modern bird species share many genetic similarities.
C.
Modern bird species are all genetically identical.
D.
Modern bird species do not share any genetic similarities.

Answer 1

Answer: B. Modern bird species share many genetic similarities.

Step-by-step explanation:

When organisms are said to have a common ancestor, it means that they share many genetic similarities but are not identical due to evolution and cross-breeding. For instance, siblings may have the same parents but they will not be genetically identical even though they have a lot of similar traits owning to their parents have different traits.

The same is true for birds. They share the genetic characteristics of their common ancestor but as time went on and evolution took place, they changed in some ways and so are no longer genetically identical.