Conventional Wisdom Holds That Oxpeckers Remove Ticks from the Backs

question 15

Multiple Choice

Conventional wisdom holds that oxpeckers remove ticks from the backs of cattle on which they feed in a mutualistic relationship,and the cattle tolerate the oxpecker's presence because the birds help remove parasites.Weeks (2000) performed observational experiments in Zimbabwe and demonstrated that the relationship between oxpeckers and cattle was not the removal of parasites but that the oxpeckers are ________.

• A) mutualistic, but serve only to remove earwax from the cattle on which they feed
• B) in fact parasitic, and create and feed on wounds they make, and also feed on earwax in the cattle
• C) mutualistic and only feed on open wounds that have already been created by feeding ticks
• D) parasitic and feed on earwax and the open wounds they create during the removal of the earwax
• E) mutualistic and feed on open wounds that have already been created by ticks, and additionally feed on earwax

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Definitions:

Marginal Productivity

The additional output resulting from the use of one more unit of a factor of production, holding other factors constant.

Labor-saving

Technologies or methods that decrease the amount of work required to produce goods or services, often leading to increased efficiency.

Marginal Productivity

The additional output that results from using one more unit of a factor, holding all other inputs constant.

Labor-saving

Technologies or methods that reduce the amount of work required to produce goods or services, often leading to increased efficiency and productivity.