Robert Paine Was the First Biologist to Use the Term

question 11

Multiple Choice

Robert Paine was the first biologist to use the term keystone species in the 1960s. He was studying food webs in the rocky, intertidal pools in the Pacific Northwest. At one of his study sites, the dominant organisms in the tidal pools were mussels, barnacles, whelks, and a species of starfish known as Pisaster ochraceus . To examine the relationship between these species, Paine set up an experiment. In one area, he removed all the starfish from the tidal pools, and in an adjacent area, he left the tidal pools as he found them. Prior to removing the starfish, he sampled all the organisms in each pool. After two months, he repeated this sampling. A summary of his results is illustrated in the graph below.

At one of Paine's study sites, the dominant organisms in the tidal pools were mussels, barnacles, whelks, and a species of starfish know as Pisaster ochraceus . These organisms together are a(n) __________.

• A) population
• B) community
• C) ecosystem
• D) niche

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Definitions:

Anchor

A key piece of information used as a reference point for decision-making or assessment, often in negotiations or estimations.

Attitudes

A psychological tendency expressed by evaluating a particular entity with some degree of favor or disfavor.

Human Mind

The set of cognitive faculties including consciousness, perception, thinking, judging, and memory, that is the essence of an individual's mind.

Society

A group of individuals involved in persistent social interaction, or a large social group sharing the same geographical or social territory, typically subject to the same political authority and dominant cultural expectations.