Some Birds Follow Moving Swarms of Army Ants in the Tropics

question 31

Multiple Choice

Some birds follow moving swarms of army ants in the tropics. As the ants march along the forest floor hunting insects and small vertebrates, birds follow and pick off any insects or small vertebrates that fly or jump out of the way of the ants. This situation is an example of what kind of species interaction between the birds and the ants?

• A) consumption
• B) commensalism
• C) parasitism
• D) mutualism

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Definitions:

Accounting Rate of Return

The accounting rate of return (ARR) is an accounting metric that measures the profitability of an investment by dividing the average annual profit by the initial investment cost.

Capital Budgeting

The process of evaluating and selecting long-term investments that are in line with the goal of shareholders' wealth maximization.

Time Value of Money

A financial principle that posits money available now is worth more than the same amount in the future due to its potential earning capacity.

Hurdle Rate

A financial metric indicating the minimum return on investment required for a project or investment to be considered acceptable.