Evolutionary arms races
A selection of talks on Immunology & Inflammation
Hello, and welcome to the lecture on Evolutionary Arms Races. I'm Mark Pagel. The idea of an arms race is a central concept in evolution. And we will see over the next 45 minutes or so, that they are widespread and common in nature, and that the shape animal morphology, behavior, and even their genetics. The lecture will be divided into three parts. In the first, we will define arms races, and distinguish them from things that are not arms races. The second part of the lecture will take up features of arms races, and look for those features in real biological examples. The third part will present three case studies of arms races in more detail. Throughout the lecture, scientific papers will be mentioned, and a list of these will be provided at the end.
Let's begin by defining what we mean by an arms race. The term is often used to describe competitive situations in which the goal is merely to stay ahead of another competitor. The competitions might be among individuals, among nations, or between biological species. The key feature of an arms race is there is no absolute goal. Rather, arms races are typified by one party having the continuing goal of being better at, or being able to deflect whatever the other party is doing. It's of some interest that according to the Oxford English Dictionary the phrase was first used in print in 1936, referring to the buildup of arms leading to World War II. However, the concept has been around far longer. For example, we know that Darwin was aware of it.
Perhaps, the best known arms race, and the contemporary event for which the phrase is most often used was the competition following the World War II between the United States and the Soviet Union for supremacy in the number and sophistication of nuclear missiles. The graphic shows the dramatic buildup in the numbers of nuclear missiles by both sides in the four decades following World War II. For many people, one of the most dramatic events of that era was the Soviet premier, Nikita Khrushchev going to the United Nations, removing his shoe and then banging it on the table as he addressed the US ambassador shouting, we will bury you. The two sides had so many missiles each, that they were said to be following a policy of mutually assured destruction, aptly called MAD. The astronomer Carl Sagan, memorably described the policy of mutually assured destruction as like, two men standing waist deep in gasoline. One has three matches, the other has five. Other well-known political and economic arms races include