A long-standing theoretical tradition in clinical psychology and psychiatry sees deliberate self-harm , such as wrist-cutting, as “functional”—a means to avoid painful emotions, for example, or to elicit attention from others. There is substantial evidence that DSH serves these functions. Yet the specific links between self-harm and such functions remain obscure. Why don’t self-harmers use less destructive behaviors to blunt painful emotions or elicit attention? Economists and biologists have used game theory to show that, under certain circumstances, self-harmful behaviors by (...) economic agents and animals serve important strategic goals. In particular, “costly signals” can credibly reveal a “private state” in situations where verbal claims and other “cheap” signals might be disbelieved. Here, DSH is scrutinized using signaling theory, and a variant, the theory of bargaining with private information. The social contexts and associated features of DSH suggest that it might be a costly, and therefore credible, signal of need that compels social partners to respond. (shrink)

Here we argue that the concept of strategies, as it was introduced into biology by John Maynard Smith, is a prime illustration of the four dimensions of theoretical biology in the post-genomic era. These four dimensions are: data analysis and management, mathematical and computational model building and simulation, concept formation and analysis, and theory integration. We argue that all four dimensions of theoretical biology are crucial to future interactions between theoretical and empirical biologists as well as with philosophers of biology.

Humans hunt and kill many different species of animals, but whales are our biggest prey. In the North Atlantic, a male long-fi nned pilot whale (Globiceph- ala melaena), a large relative of the dolphins, can grow as large as 6.5 meters and weigh as much as 2.5 tons. As whales go, these are not particularly large, but there are more than 750,000 pilot whales in the North Atlantic, traveling in groups, “pods,” that range from just a few individuals to a (...) thousand or more. Each pod is led by an individual known as the “pilot,” who appears to set the course of travel for the rest of the group. This pilot is both an asset and a weakness to the pod. The average pilot whale will yield about a half ton of meat and blubber, and North Atlantic societies including Ireland, Iceland, and the Shetlands used to manipulate the pilot to drive the entire pod ashore. In the Faroe Islands, a group of 18 grassy rocks due north of Scotland, pilot whale hunts have continued for the last 1200 years, at least. The permanent residents of these islands, the Faroese, previously killed an average of 900 whales each year, yielding about 500 tons of meat and fat that was consumed by local residents. Hunts have declined in recent years. From 2001 to 2005, about 3400 whales were killed, yielding about 890 metric tons of blubber and 990 metric tons of meat. The whale kill, or grindadráp in the Faroese language, begins when a fi shing boat spots a pod close enough to a suitable shore, on a suitably clear day. A single boat, or even a small group of fi shermen, is not suffi cient to trap a.. (shrink)

Humans are incapable of acting as utility maximisers. In contrast, the evolutionary process had considerable time and computational power to select optimal heuristics from a set of alternatives. To view evolution as the optimising agent has revolutionised game theory. Gigerenzer and his co-workers can help us understand the circumstances under which evolution and learning achieve optimisation and Nash equilibria.