What Does the Following Phylogeny Suggest

question 19

Multiple Choice

What does the following phylogeny suggest?

• A) The bilaterian ancestor likely had a nervous system arranged like cnidarians.
• B) The bilaterian ancestor may have had a diffuse net of nerves.
• C) The evolution of a single nerve cord occurred in the common ancestor of all animals.
• D) a and b
• E) a, b, and c

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Definitions:

Conditioned Response

A learned reaction to a previously neutral stimulus that has been repeatedly paired with an unconditioned stimulus causing an automatic response.

Taste Aversions

A learned response to eating spoiled or toxic food, resulting in an aversion to the taste of foods associated with illness or poor experiences.

Insight Learning

A cognitive process in which a problem is suddenly understood or solved through an "aha" moment without trial-and-error behavior.

Vicarious Learning

A process of learning that occurs by observing the behaviors of others, their consequences, and deciding whether to imitate that behavior.