Concept explainers
What Good Are Wisdom Teeth and Ostrich Wings?
Ostrich wings are vestigial because they are too rudimentary to perform the function for which they evolved in the species’ flying ancestor. Nonetheless, the ostrich uses its wings for other purposes. For example, an ostrich may extend its wings to the side while running, to help maintain balance, and it may spread its wings as part of a threat display. These uses show that evolution by natural selection can sometimes repurpose vestigial structures that have lost the function for which they originally evolved. But whether a vestigial structure remains useless or acquires a new function, it is homologous to the version that retains its original function in other organisms and provides evidence of common ancestry. But are all similarities between different organisms the result of shared ancestry?
Want to see the full answer?
Check out a sample textbook solutionChapter 15 Solutions
Biology
- Why was the evolution of jaws selected for? (Choose All That Apply) There's more than one correct answer. Please highlight the correct answer it allowed for the evolution of teeth it increased the efficiency of feeding it increased respiratory efficiency it increased the ability to grab foodarrow_forwardBirds do not have teeth. Do you think they have adaptations to processing different types of food, comparable to the diversity seen in mammals? If so, what might these adaptive differences be?arrow_forwardHuman embryos have tails which become tail bones before birth. Tails also appear in fish, reptiles, amphibians, birds, and mammals Humans also have hair and produce milk to nourish the young, which is unique to mammals. What does this indicate? a close evolutionary connection between humans and many other mammals a very distant evolutionary connection between humans and many other mammals a very distant evolutionary connection between humans and many other reptiles a close evolutionary connection between humans and many other reptilesarrow_forward
- Birds are unique because they have modified forelimbs which serve as wings and a body covered in feathers. However, just having wings and feathers does not mean that an organism can fly (look at the ostrich and penguin!). Please discuss at least 3 of these additional characteristics/adaptations that are required in order for birds to fly.arrow_forwardPharyngeal slits are which of the following? Question 24 options: a) Openings in the pharynx. In aquatic chordates they allow for exit of water that enters the mouth. b) Elongations of the posterior portion of the body. Use for locomotion in fish, or balance in some terrestrial vertebrates. c) Flexible, rod-shaped structures that grows from mesoderm. Gives support to an animal in embryonic development of chordates or for entire life depending on the species. d) Tissues that produces thyroid type hormones. e) Hollow tubes that develops from ectoderm. Develops into the central nervous system.arrow_forwardWhat Australian marsupial has habits and appearance similar to a ground hog? Where are there over 250 species of fruit flies (Drosophila)? In what group of mammals the did the number of cusps and side-to-side ridges on the teeth increase?arrow_forward
- Which of the following characteristics are indicative of mammals? post-orbital bar/closure homodont teeth heterodont teetharrow_forwardAn example of paedomorphosis would be a ____. salamander that becomes sexually mature while still retaining its gills moose that has antlers that are much larger than its ancestors primate with a smaller head than its ancestors duck that did not have webbed toes due to lack of the paracrine hormone gremlinarrow_forwardAn example of peramorphosis would be a____. salamander that becomes sexually mature while still retaining its gills moose that has antlers that are much larger than its ancestors primate that has a shorter mandible than its ancestors horse that has fewer toes than its ancestorsarrow_forward
- Fossilized remains of prehistoric mastodons show anatomical similarities to modern-day elephants. These similarities provided the first evidence that mastodons were related to modern-day elephants. Which of the following is the BEST additional evidence that mastodons were related to elephants? A. Mastodons walked on four legs like modern-day elephants. B. Mastodon tissues contained proteins with similar amino acid sequences compared to modern-day elephants. C. Mastodon fossils were found in the same area where modern-day elephants live. D. Mastodons ate a diet similar to that of modern-day elephants.arrow_forwardThe nonfunctional pelvis and hind limbs found in some snakes support which statement about evolution?Mutations tend to make species evolve to resemble other species in their environment.Snakes evolved from the same common ancestor as species in which these structures are functional.Selection pressures promoting snake evolution ceased before snake anatomy was well adapted.Snakes began to evolve these structures, but selection pressures did not favor them.arrow_forwardPrehistoric remains of animals consist almost exclusively of bones and teeth. Why?arrow_forward
- Biology: The Dynamic Science (MindTap Course List)BiologyISBN:9781305389892Author:Peter J. Russell, Paul E. Hertz, Beverly McMillanPublisher:Cengage Learning