What Community Characteristics Promote Recent and Current Bio-Diversification? An Investigation of Community-Level, Ecological Correlates of Rapid Diversification in Replicate, Temperate Angiosperm Genera
- Lesley Lancaster
|Postdoctoral Fellow||1st March 2009—16th May 2012||Participant List|
Processes behind patterns of angiosperm biodiversity in temperate regions are little understood. Further, we do not know whether particular communities that currently support relatively high temperate biodiversity are the same communities that promote the evolutionary process of diversification (i.e. speciation). I propose to compare diversification rates within selected angiosperm genera that inhabit a range of temperate communities using published phylogenies and sequence data, focusing on clades in which nodes can be or have been dated. I will then map habitat and community characteristics that have been hypothesized to be general factors promoting rapid diversification. I will apply method-of-moments estimators of diversification rates (using a stochastic birth-and- death model of diversification) both within and between selected genera to look for correlations between recent rapid divergence within clades and characteristics of habitat or community type occupied by those clades. Previous studies of diversification processes have targeted particularly diverse clades or communities and then attempted to draw conclusions about which factors led to their respective high species numbers. However, my proposed method will allow for more rigorous hypothesis testing and generalization of conditions promoting diversification by starting with a phylogenetically diverse array of genera and ecological conditions within which to compare habitat characteristics and diversification rates. Furthermore, recent advances in estimating diversification rates will allow me to disentangle the relative effects of speciation vs. extinction on diversification rates. These methods have seldom been applied to diversification rates within less inclusive crown clades, which may be the most relevant for understanding the processes of speciation and conservation of habitat features or communities that are most likely to be sites of current speciation and/or extinction.
|Type||Products of NCEAS Research|
|Journal Article||Goldberg, Emma E.; Lancaster, Lesley; Ree, Richard H. 2011. Phylogenetic inference of reciprocal effects between geographic range evolution and diversification. Systematic Biology. Vol: 60(4). Pages 451-465. (Online version)|
|Journal Article||Lancaster, Lesley. 2010. Molecular evolutionary rates predict both extinction and speciation in temperate angiosperm lineages. BMC Evolutionary Biology. Vol: 10(162). Pages 1-10.|
|Journal Article||Lancaster, Lesley; Kay, Kathleen M. 2013. Origin and diversification of the California flora: Re-examining classic hypotheses with molecular phylogenies. Evolution. Vol: 67(4). Pages 1041-1054. (Online version)|