The Cambrian Explosion Resulted in the Evolution of More Than

question 44

Multiple Choice

The Cambrian explosion resulted in the evolution of more than 17,000 species of an animal known as the trilobite.The sheer number of trilobite fossils found in modern times suggests that trilobites were very abundant,perhaps the rulers of the seas.Today,no living descendants of this group exist.What happened?

• A)Because trilobites evolved before the first mass extinction,it is possible that any of the five mass extinctions could have wiped out the entire group.
• B)In order to disappear from the planet entirely,trilobites must have undergone the process of adaptive radiation.
• C)It is unlikely that trilobites could have survived the increase in atmospheric oxygen once the process of photosynthesis had evolved.
• D)Being so plentiful,trilobites must have been the major food source for terrestrial dinosaurs. The extinction of the trilobite may have caused the mass extinction of dinosaurs.

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Definitions:

Interval Scale

A scale of measurement in which there are equal distances between measurements but no absolute zero reference point.

Equal Distances

In mathematics and statistics, a concept where the separation between points or values in a sequence or scale is consistent across the sequence.

Absolute Zero

The point on a scale at which no quantity of what is being measured exists, representing a complete absence of that entity.

ACT

A standardized test used for college admissions in the United States, measuring skills in English, mathematics, reading, and science, with an optional writing test.