Sponges and Cnidarians Are Among the Fossilized Animals Found in Both

question 43

Multiple Choice

Sponges and cnidarians are among the fossilized animals found in both the Ediacara Hills and the Burgess Shale from the Rocky Mountains of British Colombia. This observation requires that

• A)ancestral sponges and cnidarians had formerly been terrestrial animals.
• B)North America and Australia were united to each other about 550 million years ago (mya).
• C)land that now comprises the Ediacara Hills and the Rocky Mountains was underwater about 550 million years ago.
• D)only sponges and cnidarians existed at the time the sediments were deposited.

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Definitions:

Null Hypothesis

A statement suggesting that there is no significant difference or relationship between specified populations, any observed effect is due to sampling or experimental error.

Statistical Hypothesis

Statement about an expected outcome or relationship involving population parameters.

Expected Outcome

The anticipated result or set of results from a scientific experiment or a statistical analysis.

Sampling Error

The difference between a sample statistic and the corresponding population parameter, which arises simply because the sample is not a perfect representation of the population.