PPT Slide
Much dispersalist biogeography was done on a stabilist earth model, and some of these workers were among the last “die-hards” against continental drift. But if the earth is not dynamic, then some way has to be found to explain distributions such as those where closely related groups exist only in Africa and South America. This mechanism is always dispersal. The means of dispersal can include:
- wind, including hurricanes, tornadoes, the jet stream
- water, including rafting or lensing
- hitchhiking on other organisms, such as bird’s feet
The emphasis on individual groups of species means that workers explain distribution patterns on a group by group basis, and are unable to generalize to common causes.