The Following Questions Refer to the Evolutionary Tree in Figure

question 31

Multiple Choice

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.


-According to this tree, what percent of the species seem to be extant (i.e., not extinct) ?

• A)25%
• B)33%
• C)50%
• D)66%
• E)75%

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Definitions:

Opponent Process Theory

A psychological and neurological model that accounts for a wide range of behaviors, including color vision and emotions, by proposing that elements operate in pairs with opposite actions.

Colour Vision

The ability of the visual system to distinguish between light based on its wavelength composition.

Additive Colour Mixing

A process by which colors are created by mixing different colors of light, with primary colors including red, green, and blue.

Subtractive Colour Mixing

A process involving the mixing of colored pigments where the combined colors absorb certain wavelengths of light and reflect others, creating a new color.