Use the Diagram Showing the Spread of the Cattle Egret

question 44

Multiple Choice

Use the diagram showing the spread of the cattle egret, Bubulcus ibis, since its arrival in the New World, to answer the question.

The range of cattle egrets has expanded between 1937 and today. How would an ecologist likely best explain the expansion of the cattle egret?

• A) Climatic factors, such as sunlight, temperature, and precipitation, provide a suitable habitat for cattle egrets.
• B) There are no predators for cattle egrets in the New World, so they continue to expand their range.
• C) The abundant area and little competition with other birds occupying similar habitats met the biotic and abiotic requirements of the cattle egret expansion.
• D) The first egrets to colonize South America evolved into a new species capable of competing with the native species of herons and egrets.

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Definitions:

Medulla oblongata

A region of the brainstem that controls vital body functions such as breathing, heart rate, and blood pressure.

Brainstem

The part of the brain that connects the cerebral cortex to the spinal cord, controlling vital functions like heartbeat and breathing.

Cerebrum

The largest part of the brain; it mainly includes the cerebral hemispheres.

Spinal cord

The cylindrical bundle of nerve fibers and associated tissue that is enclosed in the spine and connects nearly all parts of the body to the brain.