Goser, B. Netherlands Institute for Ecology, Centre for Limnology (NIOO-CL), goser@cl.nioo.knaw.nl

 
CLONAL DIFFERENCES IN LIFE HISTORY CHANGES OF DAPHNIA INDUCED BY INTRASPECIFIC INFOCHEMICALS
 
Several species of Daphnia exhibit a change in life history induced by intraspecific infochemicals. The magnitude of change increases with increasing conspecific density. Knowledge exists about varying responses of different species to these infochemicals, but no information is available about clonal differences in the response to the infochemicals. I examined 5 clones of Daphnia pulex and 3 clones of Daphnia galeata originating from different habitats, whether they change their life history data in the presence of intraspecific infochemicals in a different way. The animals were cultured individually in water containing no infochemicals, as well as in water conditioned by 50 to 400 conspecifics per liter. In both species, mortality, juvenile development time, growth, and reproduction of tested females were influenced by the infochemicals, as well as neonate length. Moreover, clonal life history traits varied as a function of the concentration of infochemicals. In Daphnia pulex, for example, with increasing infochemical concentration clutch size was reduced in three clones, but one clone did not respond and clone five produced the most eggs per clutch at low infochemical concentrations. The evolutionary potential of this genetic variability is discussed.
 
Day: Thursday, Feb. 4
Time: 04:45 - 05:00pm
Location: Hilton of Santa Fe
 
Code: SS24TH0430H