Handicap principle

Definition

The handicap principle is a hypothesis that suggests individuals of higher fitness can afford to produce costly signals that are otherwise detrimental. These signals serve as honest indicators of their genetic quality to potential mates or rivals.

5 Must Know Facts For Your Next Test

1. The handicap principle was proposed by Israeli biologist Amotz Zahavi in the 1970s.
2. A classic example is the peacock's tail; its size and brightness signal good health and genetic fitness despite being a survival disadvantage.
3. Handicap signals must be costly to ensure they cannot be easily faked by low-quality individuals.
4. This principle helps explain why certain extravagant traits persist through natural selection despite their apparent disadvantages.
5. It underscores the role of sexual selection in adaptive evolution, where mate choice drives the development of such handicaps.

Review Questions

• Who proposed the handicap principle and when?
• Why must handicap signals be costly?
• How does the handicap principle relate to sexual selection?

Related terms

Sexual Selection: A mode of natural selection where certain traits increase an individual's chances of mating and passing on genes.

Signaling Theory: A theory that explores how organisms communicate through various traits or behaviors which carry specific information.

Adaptive Evolution: The process through which populations become better suited to their environment over time via beneficial traits.