It Is Difficult to Imagine How Only Part of an Adaptation

question 25

Multiple Choice

It is difficult to imagine how only part of an adaptation could function, but Darwin explained this. How would he answer the question, "What good is 5% of an eye?"

• A) Once an organism has the first 5% of an adaptation, the rest will quickly evolve.
• B) Five percent of an eye is always better than a full eye since it is easier to grow. The difficulty is in explaining fully formed eyes.
• C) Since variation is random, we don't expect to see more than about 5% of an eye in any species.
• D) Five percent of an eye, perhaps a simple light-sensitive spot, is often better than having no eye at all.

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Definitions:

Observational Study

A type of research in which the investigator observes and records behavior or outcomes without manipulating the study environment or subjects.

Ethical Concern

Issues or situations that require careful consideration of principles of right and wrong in making decisions.

Placebo Drug Studies

Research studies that investigate the effect of a treatment, in which some participants receive a placebo, or inert substance, to compare against the effects of actual drugs.

Experimental Group

A group of subjects in an experiment who are exposed to the variable under investigation, used to determine the effect of a treatment or intervention.