Mikael Fortelius and I wrote a blog post in Nature Ecology and Evolution to accompany our recent paper on The Red Queen. It starts like this.
Leigh Van Valen once thought that species should age: the longer a species has been around, the more likely it should be to go extinct. He tried to test this on fossil data and found to his surprise that they don’t seem to do so – old and young species with similar ways of life (inhabiting the same adaptive zone) have about the same probability to go extinct at any point in time. This is roughly similar to the decay of radioactive nuclei and means that adaptive zones (or in practice the biological groupings that reflect them, such as families and orders) have characteristic half-lives, just as radioactive elements do.
And our Nature paper is here.