Select the correct answer from each drop-down menu. Sharks, whales, and dolphins share similar features such as body shape and the position of fins. However, sharks have gills for breathing,
while whales and dolphins have lungs. These differences indicate that the organisms share a common ancestor for
Whales also possess a vestigial pelvic bone. The presence of the pelvis bone may indicate that whales

Transposon can cause mutations in genes at or near the site of transposon insertion. it is possible for these elements to transpose away from their original site, causing a reversion of the mutant phenotype. in some cases, however, even more severe phenotypes appear when these elements excise from this site, due to events at or near the mutant allele. what might be happening to the transposon or the nearby gene to create more severe mutations?