Question

postcranial skeletal pneumaticity (psp) refers to the presence of extensions of an animals lungs and air sacs inside its bones. these extensions are known as pneumatic diverticula. vascularity and other identifying characteristics of pneumatic diverticula tend not to fossilize, so paleontologists have relied on studies of living bird species to document these qualities, augmenting their findings from fossil analysis to glean additional insights into the respiratory systems of extinct genera such as tyrannosaurus, euhelopus, and other cretaceous theropods and sauropods that may have also exhibited psp. which choice best describes the function of the underlined portion in the text as a whole? a. it presents information about the fossilization of pneumatic diverticula that has led paleontologists to question the applicability of studies of certain living species. b. it accounts for disagreements among paleontologists about how the respiratory systems of certain extinct genera functioned. c. it highlights an issue with fossils that previously led paleontologists to misidentify certain characteristics of pneumatic diverticula. d. it indicates why paleontologists have used another approach in addition to fossil analysis to learn about certain aspects of pneumatic diverticula.

Explanation:

The text discusses how paleontologists have used studies of living bird species (in addition to fossil analysis) to learn about pneumatic diverticula. This indicates an alternative approach (using living species' studies) to understand aspects of pneumatic diverticula, which is what option D is about. Option A is about information on fossilization applicability for living species studies, which is not the main function. Option B is about accounting for disagreements, not relevant. Option C is about highlighting an issue with fossils leading to mis - identification, but the text focuses on using another approach (living species) not just an issue with fossils.

Answer:

D. It indicates why paleontologists have used another approach in addition to fossil analysis to learn about certain aspects of pneumatic diverticula.