tiated skill. They examined four findings that they said had been substantiated in previous studies: greater aggressiveness in male mammals; greater fearfulness in male rodents but also in female humans and “perhaps in primates generally”; mammalian male superiority at spatial tasks; and greater female linguistic ability in humans (or “man,” as they put it). The robustness of all these generalizations is questionable, with, as we have seen, the possible exception of the third. Males are more aggressive, Gray and Buffery claim, because male animals always have dominance hierarchies into which females are subsumed and in which females are always subordinate. As it turns out, this is quite untrue, as I discussed in the chapter on dominance, and furthermore the significance of dominance hierarchies is uncertain for many natural populations of animals. The psychologists seem to be suffering from misconceptions about a scala naturae as well; they conclude that a phenomenon seen in rats, mice, a monkey or two, and some subgroups of humans must perforce be general to all mammals. The reasoning behind the claim that female rats and mice are less fearful than males of the same species and more fearful than human males is a bit hard to follow, but seems to have to do with women being “more prone than men to phobias (and especially agoraphobia) and reactive depression; they also score more highly than men on personality tests measuring neuroticism and introversion . . . as well as on tests measuring . . . susceptibility to anxiety” (p. 98). The evolutionary justification for this is unclear; is being fearful or being bold the adaptation? The answer would seem to depend on the environmental circumstances. In addition, the authors do not seem to consider that social influences and discrimination against women might enter into some of the findings. Many feminist scholars, such as Phyllis Chesler, have argued that depression, for example, is an expected and in many ways reasonable response to an unjust world. Regardless, biologists have not followed up this particular sexual dimorphism, either in animals or in humans. Gray and Buffery thought that the greater linguistic ability of women stemmed from the prolonged mother-infant bond that occurs in humans; they suggested that mothers were thus in a better position to teach their children to speak than any man would be, and hence women were subject to differential selection because they were the instructors for the society. Why such a sophisticated ability would evolve only to be squandered on individuals babbling in words of single syllables is again not addressed. Neither is the problem of teaching sons, boys presumably being the less
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human evolutionary perspectives