Psychology: Concepts and Applications 3e   Halonen
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Classifying Animals

Is a fox more like a cat or a coyote? The answer depends in part on where you grew up, but not entirely. For thousands of years, people around the world have thought about which creatures "belong together." Some researchers argue that humans are born with certain rules for categorizing animals.

López et al. (1997) looked at how Michigan college students and Itzaj-speaking natives of the Pčten rainforest in Guatemala classified local mammals. Both the Michigan students and the Itzaj grouped animals according to size and degree of ferocity. However, Itzajs had much more detailed classifications for small animals. They sorted the animals into smaller groups by features such as the markings on the animals' coats, whether the animals live in the forest or the village, or, in one case, by the fact that an animal "sleeps in the hollows of trees and snores loudly." Yet, overall, both the Americans and Itzajs made the same distinctions between animals, like large predators and large non-predators, and put animals that live in both places into the same categories. While a few specific instances, like foxes, which the Itzaj call "forest cats,” were different, the Americans and Itzajs share basic concepts about animals in the world.

Increases in IQ Test Scores

Children's IQ test scores can vary from year to year, depending on factors like their lives at home and their nutrition level. Sometimes, an entire country's IQ goes up at once.

Alan Carr (1993) surveyed the intelligence test results for Irish primary school children between 1972 and 1992. All the children took a multiple-choice test called Raven's Progressive Matrices. This test requires test-takers to look at a sequence of drawings, and then select the drawing that continues the pattern. Over the course of twenty years, the children's median IQ rose from 100 to 110 points, and the number of children who scored in the "superior" range of the test rose from five to seventeen percent.

Obviously, there is no great genetic difference between the 1972 children and the 1992 children. The people in Ireland are the same folks who have been living there for many, many years. Irish children today probably have more time for and access to intellectual stimulation, like computers, than their parents did. Who knows how bright the children of 2012 will be?

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