In England, at a Time When Milk Was Still Delivered

question 37

Multiple Choice

In England, at a time when milk was still delivered to doorsteps each morning in foil-capped glass bottles, a songbird called the great tit started pecking through the caps and drinking the cream in the necks of the bottles. This behavior spread through the great tit population in a matter of years. The emergence and spread of this behavior probably depended on

• A) trial-and-error learning plus habituation.
• B) trial-and-error learning plus social learning.
• C) trial-and-error learning plus imprinting.
• D) habituation plus social learning.

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Definitions:

Spleen

An organ adjacent to the stomach that filters blood, disposes of worn-out red blood cells, and helps fight infection.

Lymph Node

Encapsulated mass of lymph tissue found among lymph vessels.

Thymus Gland

An immune system gland located behind the sternum that produces T-cells for the adaptive immune response.

Lymphatic Nodule

Small accumulation of lymph tissue lacking a distinct boundary.