In 1998,researchers found that genes similar to the Drosophila gene tinman are necessary for heart development in vertebrates.What can you conclude about the ancient bilaterian ancestor of insects and vertebrates over 500 million years ago?
A)The fly species that eventually gave rise to vertebrates used tinman to make a heart.
B)Something about heart development requires a gene to have a tinman-like sequence,but the vertebrate and invertebrate genes arose by convergent evolution -- so the ancestor had a similar but not homologous gene.
C)The ancient ancestor lacked a heart,but already had a tinman-like gene.
D)The ancestor had a heart-like structure that was specified by a tinman-like gene.

Question

Quizplus · Accepted Answer

The finding that genes similar to the Drosophila gene tinman are necessary for heart development in vertebrates suggests that the ancient bilaterian ancestor of insects and vertebrates over 500 million years ago had a heart-like structure that was specified by a tinman-like gene. This is supported by the fact that both insects and vertebrates use a tinman-like gene for heart development, indicating that this gene was already present in their common ancestor.

In 1998,researchers Found That Genes Similar to the Drosophila Gene