Frozen Evolution. Or, that’s not the way it is, Mr. Darwin. A Farewell to Selfish Gene.

In the typical case, a mass extinction event is accompanied by a substantial reduction in biodiversity, very frequently not only on a local, but also on a global scale.The individual ecosystems degrade substantially and only a few species remain, which were originally rare before the mass extinction event but subsequently relatively abundant.For example, the beginning of the Mesozoic was characterized by an enormous expansion of stromatolites, while the beginning of the Tertiary witnessed an enormous increase in Foraminifera of the Guembelitria group (Erwin 1998).Many of these species tend to be characterized by small body dimensions – this phenomenon has been described as the Lilliputian phenomenon.These pioneer species are apparently capable of utilizing the degraded environment effectively but are not capable of surviving in competition with other species under normal conditions.Thus, they are a sort of macro-evolutionary analogy of ecological r-strategists.However, in contrast to r-strategists, they apparently did not adapt evolutionarily to the conditions prevailing after mass extinction, but their adaptation, to be more exact exaptation, occurred accidentally or as preadaptation through the action of different selection pressures.