Insect wings may have begun to evolve as lateral extensions of the body that were used as heat dissipaters for thermoregulation. When they had become sufficiently large, these extensions became useful for gliding through the air. Additional selection refined them as flight- producing wings. If this hypothesis is correct, modern insect wings would be an example of .

Which part of cellular respiration must occur before any of the other steps can occur

12) several teeth were found in an area of flat land covered with trees and plants. the teeth were examined by a paleontologist, and it was determined that the teeth came from a shark. they found many other shark teeth in this area. however, the people who discovered the teeth were puzzled, because there was no source of water near where the fossils were found. what is the paleontologist's best explanation for why the teeth were found in this area? a) sharks used to live on flat land. b) this area was once covered with salt water. c) this area was once covered with freshwater. d) someone buried the shark teeth deep in the ground.

16 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. hoy while whales and dolphins have lungs. these differences indicate that the organisms share a comme whales also possess a vestigial pelvic bone. the presence of the pelvis bone may indicate that whales reset next