The role of cryptic riverine fish diversity in the generation oflacustrine species flock.

Paul Nichols

University of Hull (Website)

Supervisors: Dr Domino Joyce, Dr Cock van Oosterhout, Prof. George Turner, Dr Martin Genner

I'm investigating the hypothesis that adaptive radiations can be triggered by hybridsation events between colonising lineages, using a recently discovered pair of genetically divergent (ca 4 Myrs) but phenotypically similar cichlid fish - Astatotilapia calliptera,which is the only member of the 650-species strong Malawian haplochromine radiation to be found both in Lake Malawi and in the surrounding river systems. The two lineages are largely allopatric (one within the Malawi catchment and the other outside it) but have a small contact zone in the south of the lake. I plan to investigate the possibility that these lineages could hybridise to generate new genetic combinations resulting in phenotypic novelty (and possibly adaptive radiation). I will examine whether or not these lineages have evolved a measure of reproductive isolation using laboratory mating trials, whether there is hybridisation in the contact zone using microsatellites, and finally, whether laboratory hybrids exhibit transgressive segregation.

Contact:
Paul Nichols
University of Hull
p.c.nichols@biosci.hull.ac.uk

Male Astatotilaplia calliptera (Katie Woodhouse)