This Thursday, Adam Meyer will be giving a talk titled:
Can spatial heterogeneity maintain multiple migration behaviors in a freshwater zooplankton?
at 12:30 in the EEB lounge (BioSciences 4338)
The seminar is hosted by the Nelson Lab
Theory and experiments suggest that spatial heterogeneity in the environment can help maintain multiple behavioural strategies. Zooplankton undergo daily vertical migration behaviours which vary depending on the environmental gradients and predation pressure in a lake. Though typically only one migration behaviour is observed per lake, zooplankton in some lakes show multiple migration behaviours that appear to co-occur for extended periods of time. In a lake with two distinct behaviours, we examined the importance of strong environmental gradients to the fitness of distinct Daphnia pulicaria phenotypes exhibiting either a shallow-water migration or a deep-water migration. Using specially designed migration robots to manipulate migration, we performed fitness bioassays where each phenotype underwent either a shallow or deep water migration for a period of two weeks. Population growth rates were estimated by measuring biomass at days 0, 7 and 14. Growth rate comparisons indicate that in the absence of predation, deep migrators should overtake shallow migrators as the most prevalent phenotype since they display higher growth rates regardless of migration behaviour. This result supports previous work showing that the deep migrators slowly increase in relative abundance from spring to fall.
Adam is an MSc candidate in the Nelson lab here at Queen’s.