Crossbill Birds Have a Beak That Is Designed to Eat

question 38

Multiple Choice

Crossbill birds have a beak that is designed to eat pine cones.If we trim the beak,the behavior disappears.This example illustrates:

• A) fixed behavior.
• B) flexible behavior.
• C) learned behavior.
• D) adaptive behavior.

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Definitions:

Meninges

The three layers of protective tissue (dura mater, arachnoid mater, and pia mater) covering the brain and spinal cord.

Arachnoid

A delicate membrane that encloses the brain and spinal cord, situated between the dura mater and pia mater.

Pia

Short for pia mater, it is the delicate innermost membrane enveloping the brain and spinal cord.