What Was the 350 Million-Year-Old Fossil Called Ichthyostega

question 14

Multiple Choice

What was the 350 million-year-old fossil called Ichthyostega?

• A)A lobe-finned fish that represents the likely ancestor to the amphibians
• B)One of the earliest known tetrapods
• C)A lizard-like stem reptile
• D)A ray-finned fish that gave rise to the amphibians
• E)The first fish-to-amphibian transitional form to have lost fin rays and gill bones,thus committing itself to a land existence

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Definitions:

Negative Reinforcement

A concept in behavioral psychology where the removal of an unpleasant stimulus in response to a desired behavior increases the likelihood of that behavior being repeated in the future.

Aversive Punishment

A form of behavior modification that involves presenting an unpleasant stimulus to decrease the likelihood of a behavior's recurrence.

Negative Reinforcement

The removal of an unpleasant stimulus to increase the likelihood of a behavior being repeated.

Electric Shock

A sudden discharge of electricity through a part of the body, which can cause a range of effects from a mild tingling to severe injury or even death.