liking part company, with liking falling dormant due to sensitization, wanting grows in intensity, s

liking part company, with liking falling dormant due to sensitization, wanting grows in intensity, seeking but failing to find satisfaction. So begins an appetite for violence, one that can turn into a craving. A craving to impress Gazelles on the Serengeti plains of Tanzania sometimes move in an exceptionally bizarre way. With legs rigidly extended, they bounce up and down like kangaroos. There is no obvious function associated with this movement. If anything, it appears energetically wasteful. If these gazelles lived in tall grass, one might think that the bouncing was designed to better see or be seen. But the Serengeti plains are flat and the grass is short. Gazelles can see for miles in this habitat and so can everything else that shares this gorgeous part of the planet with them. This includes the lions, leopards and cheetah that think of gazelles as breakfast, lunch and dinner. Why would a gazelle advertise like this? Why alert predators to your location and availability? Why not use the coloration of your fur to blend into the color scheme of the savannah, moving swiftly but imperceptibly? We can explain the gazelle’s bizarre movements — called stotting — by thinking economically, using Zahavi’s honest signaling theory that I described in Chapter 1. Whenever evolutionary biologists see a behavior that is costly, they immediately search for a potential benefit. The reason is simple: behaviors that tax an individual's chances of survival and reproduction are ultimately weeded out by the force of natural selection. There must be some benefit to the individual or to others in order to neutralize the costs. Given the ostentatious nature of the gazelle’s stotting, who benefits and how? Since the behavior is eye-poppingly interesting to human observers, one assumes that it is eye-popping to other animals on the Serengeti plains as well. Gazelles typically stot when they detect danger which, in the Serengeti, means leopards, lions and cheetah. If gazelles stot to alert other gazelles, then most gazelles should stot, at least some of the time. This is because all gazelles are vigilant, should have multiple opportunities to see these predatory cats, and should benefit from an alarm signal. But this is not what we observe. Instead, stotting seems to be reserved for those in good shape. When gazelles stot, they appear to be sending a cease and desist signal to any observant cat. If this is the gazelles’ message, then cats should selectively chase non-stotters over stotters. And when cats turn a blind eye to stotting gazelles and chase them, they should have less success than when they chase non-stotters. Stotters are turbo-charged. Stotting is simply their way of showing off. These expectations are supported by the British biologists Claire Fitzgibbon and Tim Caro who spent hundreds of hours watching gazelles and predatory cats. What they reveal is that stotting is an honest signal of condition or quality. Only gazelles in good condition can tolerate the costs of stotting. Hauser Chapter 2. Runaway desire 79 HOUSE_OVERSIGHT_012825