The velocity of species dispersal post-last glacial maximum (LGM) is an interesting question from both paleo-historical and contemporary perspectives. The apparent time lag between a location’s climate becoming suitable for a given species and that species’ arrival at that location has important implications for our
understanding of the relationship between climate variables such as temperature and moisture and the dispersal ability of plants. Our knowledge of species dispersal rates underlies assumptions
required for the interpretation of pollen and sediment records, biogeochemical reconstructions, and other endemic species distributions. From a contemporary perspective, our expectation of future species distributional shifts in response to a warming climate can be informed by historic range expansion since the LGM. Thus it is important to correctly estimate those dates and rates. Elias (2013) attempts to calculate tree species dispersal rates along the northwestern.
North American coast post-LGM. This area e the largest
contiguous temperate rainforest ecosystem on the planet e was
extensively glaciated during the LGM and is currently experiencing
important transformations due to climate change. Elias concludes
that tree species migration in this region, originating from the
south, was rapid: 2e4 times the rate of similar species in eastern
North America. Unfortunately, the Elias (2013) review and analysis
does not consider localized refugia for those species, or their ecology,
within southeast Alaska during the LGM; these considerations
would likely change the conclusions. Evidence for local refugia
comes from a variety of fields, and while the geographic extent
and biological communities of these cryptic refugia are still under
study, it is important t
