According to Gustafsson, crossbred pigs used a costlier strategy than domestic pigs because they were more vigilant against predators. Present an alternative hypothesis. How would you test it?
Held et al.’s study found that dominant pigs used a scrounger strategy by exploiting informed subordinate pigs, but it did not test whether subordinate pigs preferentially use a producer strategy. How would you determine if they do? Do you predict that pigs can alternate between strategies?
Chewing and biting inedible objects expends energy and does not provide nutrition. How do you reconcile this behavior with optimal foraging theory?
Glossary
Artificial selection - human control over animal breeding in order to increase the prevalence of desired traits
Conditional strategy - an inherited mechanism that allows an animal to adapt to various conditions
Contrafreeloading - the phenomenon in which an animal chooses food that requires effort to obtain even though other food is available
Domestication - the process by which humans take care of and breed animals and animals become accustomed to humans
Feral - semi-wild; a feral animal was domesticated but escaped captivity and returned to the wild
Optimal foraging theory - theory that uses natural selection to explain animals’ feeding choices
Producer - in social foraging theory, an animal that finds food
Proximate cause - a cause based on immediate reasons for a behavior, such as physiology
Resource allocation theory - theory that argues that in a particular environment, an animal’s resources are balanced between traits for breeding and traits for production
Scrounger - in social foraging theory, a dominant animal that takes food from subordinates
Social foraging - foraging in which an individual’s decisions are dependent on the actions of another forager
tereotypies - repetitive actions resulting from boredom or frustration
Ultimate cause - an evolutionary reason for a behavior
Sources
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Shows how effects of domestication on foraging strategies are similar in pigs and chickens.
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An interesting experiment that connects foraging to animal cognition and intelligence.
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A highly recommended book by an animal science expert. Connects pig behavior to farm animal welfare issues.
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A comprehensive guide to optimal foraging theory.
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Describes numerous species of hogs, including the wild boar and the domestic pig.
About the author
Arielle Layman is a senior majoring in Biochemistry and Cell Biology at Rice University. She is from New Jersey and loves animals, science fiction, and cooking and baking vegan food. Next year she will be moving to rural New Mexico to teach high school science as a Teach For America corps member.
