Equilibrium and non‐equilibrium dynamics simultaneously operate in the Galápagos islands |
| |
| Authors: | Luis M. Valente Albert B. Phillimore Rampal S. Etienne |
| |
| Affiliation: | 1. Unit of Evolutionary Biology/Systematic Zoology, Institute of Biochemistry and Biology, University of Potsdam, Potsdam, Germany;2. Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK;3. Groningen Institute for Evolutionary Life Sciences, University of Groningen, Groningen, The Netherlands |
| |
| Abstract: | Island biotas emerge from the interplay between colonisation, speciation and extinction and are often the scene of spectacular adaptive radiations. A common assumption is that insular diversity is at a dynamic equilibrium, but for remote islands, such as Hawaii or Galápagos, this idea remains untested. Here, we reconstruct the temporal accumulation of terrestrial bird species of the Galápagos using a novel phylogenetic method that estimates rates of biota assembly for an entire community. We show that species richness on the archipelago is in an ascending phase and does not tend towards equilibrium. The majority of the avifauna diversifies at a slow rate, without detectable ecological limits. However, Darwin's finches form an exception: they rapidly reach a carrying capacity and subsequently follow a coalescent‐like diversification process. Together, these results suggest that avian diversity of remote islands is rising, and challenge the mutual exclusivity of the non‐equilibrium and equilibrium ecological paradigms. |
| |
| Keywords: | Community assembly diversification dynamic equilibrium island biogeography phylogeny |
|
|
