Evolutionary History

Carabids constitute an old lineage -- they are thought to have evolved in the early Jurassic, 200 million years ago (Ponomarenko 1972). The majority of extant carabid species belong to the subfamily Harpalinae, which is thought to have radiated in the Cretaceous, some 100 million years ago (Ponomarenko 1972).

Erwin (1981, 1985) proposed the taxon pulse hypothesis to explain historical patterns of evolution of lineages within this family. This hypothesis predicts that the most primitive taxa of carabid lineages were waterside generalists in equatorial regions. As species dispersed in altitude (e.g., into forest canopies or up mountains slopes) and out of this region (to the north and south) over evolutionary time, they became more specialized. Then, these were subsequently replaced by newly evolved groups from tropical wetlands.

Despite many efforts to infer the phylogeny of carabid tribes, many deep tribal relationships remain unresolved (see Maddison et. al 1999 for a review).