Date: 04.07.2016

The origin of tropical hyperdiversity, example from Latin American butterflies

The debate between two conflicting hypotheses on the origin of tropical species may no longer be reasonable. Tropical hyperdiversity is likely the result of complex evolutionary history, and no single age nor single event seem alone to be important ...

For almost two centuries, researchers have been asking why species diversity in the tropics is richer than in temperate regions. Recently, the timing of species origins were possible to infer using genetic tools and statistical approaches based on molecular "clock" models – models that derive absolute time from mutation rates. This scientific improvement permitted the accumulation of data on species divergence times, which investigators have used to tell us the approximate ages of tropical biodiversity. Two main hypotheses appeared on scene, a Pleistocene origin or a Neogene origin of tropical hyperdiversity. The first hypothesis suggests that tropical species mostly originated during the past three million years, coinciding with the ices ages that may have shrink rainforests into small refuges wherein evolution acted to differentiate species across refuges. The second hypothesis, on the other hand, diminishes the role of ice ages and favors intense landscape changes in the past 25 million years as major contributors of species divergences (for example, new habitats for new species during uplift of mountains). In a recent contribution, Matos-Maraví showed that the debate between these two hypotheses may no longer be valid. The researcher, using divergence times of Latin American butterflies and phylogenetic methods, concluded that the evolution of tropical taxa is more complex than the two hypotheses. Butterfly species richness in the tropics is likely the result of the intricate interplay between abiotic events (ices ages, landscape changes, etc) and biotic factors (interactions between species, insects versus plants, etc).

Matos-Maraví P. (2016) Investigating the timing of origin and evolutionary processes shaping regional species diversity: Insights from simulated data and Neotropical butterfly diversification rates. Evolution: published online 17th June 2016. DOI: 10.1111/evo.12960

Back

 

CONTACT

Biology Centre CAS
Institute of Entomology
Branišovská 1160/31
370 05 České Budějovice

Staff search