Echidnas are marsupial mammals that have quills all over their body and look like placental hedgehogs. The two are not closely related. Echidnas are found in Australia and hedgehogs are found in Europe, Asia and Africa. Their resemblance is a result of which of the following? a. Adaptive radiation
b. Convergent evolution
c. Disruptive selection
d. Homologous features
e. Sympatric speciation

Even though the ostrich is a flightless bird, ostriches still possess wings that stretch approximately two meters across when fully extended. scientists speculate that when dinosaurs became extinct, some of the birds that lived during that time became land dwellers since they were able to consume the food that the dinosaurs once ate. over time, these species grew larger and heavier. eventually, the ostrich species became too big to fly. the wings found on ostriches are known as a. analogous structures. b. homologous structures. c. vestigial structures. d. symmetrical structures.