Both Ancestral Birds and Ancestral Mammals Shared a Common Ancestor

question 16

Multiple Choice

Both ancestral birds and ancestral mammals shared a common ancestor that was terrestrial. Today, penguins (which are birds) and seals (which are mammals) have forelimbs adapted for swimming. What term best describes the relationship of the bones in the forelimbs of penguins and seals, and what term best describes the flippers of penguins and seals?

• A) homologous; homologous
• B) analogous; homologous
• C) homologous; analogous
• D) analogous; analogous

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Definitions:

Critical Value

The threshold value that a test statistic must exceed in order to reject the null hypothesis in a statistical test.

Df

Short for degrees of freedom, it refers to the number of independent values in a calculation that are free to vary.

Mean Square

The average of the squares of the differences between the observed and expected values, used in various statistical methods, such as ANOVA.

Main Effect

In analysis of variance, the direct influence of an independent variable on a dependent variable, discounting interactions with other variables.