Quaternary climate oscillations and the generation of biodiversity

Activity: Talk or presentation typesInvited talk


The last 2 million years (Quaternary period) have been a period of dramatic environmental change with major shifts in
distributions and abundances of terrestrial and marine organisms. The evolutionary consequences of this were debated during
the nineteenth century but the lack of accurate relative and absolute timescales for evolution and environmental change
inhibited progress. We do now have an understanding of timescales and detailed palaeoecological work has demonstrated the
individualistic nature of species response to environmental change, but lacks a means of determining ancestry. DNA
characterization of modern populations in relation to their distributions nicely complements palaeoecological results by
contributing ancestry. Both classic palaeoecology and phylogenetics show a remarkable lack of lineage-splitting (speciation) on
these timescales, although traditional evolutionary theory leads to the expectation that major environmental changes (such as
ice ages) should lead to evolutionary change. This suggests that the factors that lead to lineage-splitting, and hence generation
of biodiversity, are more likely to found at the level of population dynamics than in the realm of major environmental changes.
Period16 Jan 2018
Held atUniversity of California, United States, California
Degree of RecognitionLocal