Refer to the Following Information to Answer the Questions Below

question 61

Multiple Choice

Refer to the following information to answer the questions below.
Fossils of Lystrosaurus, a dicynodont therapsid, are most common in parts of modern-day South America, South Africa, Madagascar, India, South Australia, and Antarctica. It apparently lived in arid regions, and was mostly herbivorous. It originated during the mid-Permian period, survived the Permian extinction, and dwindled by the late Triassic, though there is evidence of a relict population in Australia during the Cretaceous. The dicynodonts had two large tusks, extending down from their upper jaws; the tusks were not used for food gathering, and in some species were limited to males. Food was gathered using an otherwise toothless beak. Judging from the fossil record, these pig-sized organisms were the most common mammal-like reptiles of the Permian.
-Which of these is the most likely explanation for the modern-day distribution of dicynodont fossils?

• A)There had been two previous super-continents that existed at different times long before the Permian period.
• B)The dicynodonts were evenly distributed throughout all of Pangaea.
• C)The dicynodonts were distributed more abundantly throughout Gondwanaland than throughout any other land mass.
• D)The dicynodonts were able to swim long distances, up to thousands of kilometers.
• E)The dicynodonts could survive for periods of months aboard "rafts" of vegetation, which carried them far and wide, but not to the northern hemisphere.

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Definitions:

Digestion

The biological process by which food is broken down into smaller components, eventually to be absorbed into the bloodstream.

Homeostasis

A state of steady internal, physical, and chemical conditions maintained by living systems.

Insulin

A hormone produced by the pancreas that helps regulate blood sugar levels by allowing cells to absorb glucose.

Glucose

A simple sugar and an important energy source in living organisms, part of many carbohydrates.