Sex on Six Legs_ Lessons on Life, Love, and Language From the Insect World - Marlene Zuk [33]
Be that as it may, scientists don't try to replicate the five commonly used axes for personality in humans: extraversion/introversion, antagonism/agreeableness, conscientiousness, neuroticism, and openness to experience. Too many of those criteria require self-reporting, but equivalents can often be measured, for example, the frequency of fighting that occurs when animals are in a group, or the length of time it takes an animal to move through its enclosure. Gosling cautions that it is important to know the standards against which the measures are being compared; after all, he points out, if one asked whether a deadly black mamba in a room was aggressive, it would be possible to respond that it was not, if "it has attacked only two people in the last hour, well below the norm for this species of snake." Nevertheless, one would still be ill-advised to enter. There is also something called The Horse Personality Questionnaire, with categories of Dominance, Anxiousness, Excitability, Protection, Sociability, and Inquisitiveness; why horses require six descriptors while humans only need five is an interesting question.
Keeping this in mind, a wide range of animals, including several insects and spiders, show consistency in their behavior. For example, fishing spiders live at the edge of ponds and feed on insects near the water. Different individuals attack their prey with differing degrees of alacrity, and the individuals that leap upon their prey more quickly get more food. This seems like an all-around good thing, until you learn that predatory eagerness in females is also associated with a greater likelihood of killing and eating one's potential mate. Fishing spiders also respond to the threat of attack by a potential predator by quickly diving under the water and remaining submerged in an air bubble until the danger is perceived to have passed, a period that can exceed 90 minutes. J. Chadwick Johnson and Andy Sih at the University of California, Davis, found that the length of time female spiders spent submerged varied among individuals, and bold spiders—ones that emerged relatively quickly from their underwater shelter—were also likely to go after food more decisively and to respond to males that were courting them by tapping the water surface.
Because I study them, I am biased toward crickets and have always thought they had plenty of personality, with more of it, not to mention charm, than their relatives the grasshoppers. Male crickets are rather pugnacious, and the ancient Chinese often pitted them against each other in specially constructed arenas, much like miniature cockfights. Some individuals were highly prized as winners, with poems written about their prowess. And indeed, my intuition was upheld; recently, Raine Kortet and Ann Hedrick found that fighting ability in a North American cricket was not only variable among different males, but winners were more brazen about emerging from a refuge in their container after they had been disturbed in a manner simulating a predator.
Water striders are the leggy insects that dimple the water of streams and ponds all over North America; they skate over the surface, grabbing both prey and, during mating season, each other. More accurately, male water striders jump on females and attempt to mate, while the females often try to shake them off. Although they all look similarly jittery to the casual observer, the striders, too, vary among themselves in their level of activity, with relatively