Which Observations of Species Distribution Across Earth Support the Theory

Question

Which observations of species distribution across Earth support the theory of common descent?
A) All continents contain nearly identical organisms.
B) Each part of Earth contains life forms perfectly designed for that region.
C) One can see similarities in organisms that are found in close proximity, but each population has adaptations that suit the organisms to their particular habitat.
D) There are very few similarities among life forms on different tropical islands.

Accepted Answer

The observation that organisms found in close proximity share similarities but also have adaptations that suit them to their particular habitat supports the theory of common descent, as it suggests that these organisms share a common ancestor but have evolved differently due to different environmental pressures in their respective habitats.

Answer: A and C are the best.
 A is also a supporting observation, as the presence of nearly identical organisms across continents suggests that they have a common ancestry and have been dispersed across the globe. However, B and D are not supportive of the theory of common descent, as they imply that organisms are perfectly designed for their particular habitat or have unique characteristics that are not shared with other species, which goes against the idea of a common ancestor and shared evolutionary history.