If horizontal gene transfer was predominant in early evolution, how would this affect our ability to reconstruct the tree of life?
A) Horizontal gene transfer blurs the concept of species, making it difficult to delineate ancestral species.
B) Horizontal gene transfer resulted in chloroplasts that confuse the plant lineage.
C) Horizontal gene transfer places viruses firmly at the beginning of the tree of life.
D) Horizontal gene transfer means that life-forms do not share a history of common descent.

Question

Quizplus · Accepted Answer

Horizontal gene transfer would make it difficult to distinguish ancestral species and their relationships since genes would be shared among different lineages.

Answer: D
 Horizontal gene transfer means that life-forms do not share a history of common descent, so constructing a tree of life based on genetic similarities would not accurately represent the evolution of different lineages.

If Horizontal Gene Transfer Was Predominant in Early Evolution, How