A Translocation Gives Insight into the Effects of Hybridization Between wild Populations: Implications for Understanding the Distributions of Closely Related Species.

HR: 09:00h
AN: NB51B-03 [Abstracts]
TI: A Translocation Gives Insight into the Effects of Hybridization Between wild Populations: Implications for Understanding the Distributions of Closely Related Species.
AU: * hughes, J
EM: jane.hughes@griffith.edu.au
AF: Cooperative Research Centre for Freshwater Ecology, Centre for Riverine Landscapes,Griffith University, Nathan, Qld 4111 Australia
AU: Fawcett, J
AF: Cooperative Research Centre for Freshwater Ecology, Centre for Riverine Landscapes,Griffith University, Nathan, Qld 4111 Australia
AU: Cook, B
AF: Cooperative Research Centre for Freshwater Ecology, Centre for Riverine Landscapes,Griffith University, Nathan, Qld 4111 Australia
AU: Ponniah, M
EM: M.Ponniah@griffith.edu.au
AF: Cooperative Research Centre for Freshwater Ecology, Centre for Riverine Landscapes,Griffith University, Nathan, Qld 4111 Australia
AB: If two populations are separated for long enough in evolutionary time, mixing them may result in hybrids with reduced fitness. Possible consequences of this are the development of mechanisms that reduce the chance of hybridization or the extinction of one or other of the two genotypes. In 1995, a number of freshwater shrimp (Paratya australiensis) were translocated between two streams within the Brisbane River drainage. Later analysis of mitochndrial DNA revealed that the two populations were quite divergent genetically and had likely been separated for over 2 million years. Seven years after the translocation, the translocated genotype had sent the resident genotype extinct in the pool where the translocation took place, and in pools above and below in the stream. In this talk, I will present data from the next two generations and show that the translocated genotype has taken over all pools up-stream of the original site (a distance of over 2km), but has not become established more than 500 m below the site. Results suggest that survival of different genotypes within a generation are dependant on position in the stream (up-stream or downstream, but when fitness is calculated between generations, translocated genopyes are superior. Our findings will be related to a more general phylogeographic survey of the shrimp in eastern Australia.
DE: 9800 GENERAL OR MISCELLANEOUS
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly