ntbirdman
Well-known member
Thank you, Richard! I'm hanging on with my metaphorical grey matter fingernails after reading the abstract, but "overdispersed assemblages" threatens to send me spinning into the abyss of manic jargon!
Has anyone got a short (Please!) definition/explanation?
For an even shorter explanation, it's a measure of how related a community of species is. For a simple example, in a community of bird species (assemblage), if you find just one species from any particular family or genus, that's overdispersion. If you find a bunch of species in the same family or genus, say there are flocks of 10+ different warbler or sparrow species, or a wetland with a whole bunch of duck and heron species, that's underdispersion or clustering. The clustering means that across the whole phylogenetic tree of birds, the species in the community you are looking at form "clusters" in particular places on the tree rather than being evenly dispersed across it.