Dr. Jeff McKinnon

My research program is highly integrative, taking place at the interface between evolution, ecology, and behavior. And because it is readily compartmentalized into smaller subprojects and requires only a modest level of training, it is well suited to undergraduate participation.

For the last four years the major focus of my laboratory has been an NSF-funded (RUI 9981638) study of selection's role in the evolution of reproductive isolation between stream and anadromous forms of threespine stickleback. Fifteen undergraduates and I have shown that, despite a detectable effect of time (several hundred thousand years of separation in some cases) on reproductive isolation, divergent selection leads to parallel reproductive isolation, or assortative mating by selective environment, in nine populations of stream-resident and anadromous sticklebacks from six continents and islands. This is largely due to convergent evolution of size in each environment and assortative mating by size, a remarkably simple mechanism given the long separation of many populations and the vast distances. Controlling for genetic distance does not affect these results. Just this summer we have concluded a further experiment in which we manipulated female body size to experimentally test the role of size in reproductive isolation. We find that size manipulated females, whether of the stream or anadromous form, mated assortatively with wild males most similar to them in size: stream males if they are small, anadromous males if they are large.

Student researchers on this work have made over 20 conference presentations in six states and co-authored presentations made in additional states and countries. Two have won awards and had their travel paid to national meetings and in 2002 four students made successful poster presentations at the Society for the Study of Evolution meetings. Two students have already gone on to Ph.D. programs (University of Indiana and UW-Madison) and others have gained entry to Medical and Pharmacy programs. I have published results of an earlier UWW stickleback project, on the evolution of female coloration, with student co-authors (McKinnon et al. 2002). I am presently revising a manuscript based on the results described above for submission to a major journal, likely Nature; two undergraduates will be co-authors. Stickleback research will continue in my laboratory if the REU project is funded, following up the results of the speciation work and possibly returning to the study of female color evolution. In particular, we would like to evaluate further our preliminary results suggesting that male sticklebacks have the same color-preference as females, that is, for mates with red throats. We would also like to investigate the causes of divergence in male nuptial coloration between stream and anadromous forms of stickleback.

Recently my laboratory has been developing a second major project in addition to the stickleback work, this time studying the telmatherinid (a group of small fish) species flock of Sulawesi's Malili lakes. Our main emphasis is color-polymorphism evolution and the role of color polymorphisms in speciation. Thus far, students have participated in this work by collecting behavioral data from videotapes made in the field, collecting and analyzing morphological data and helping to "crunch" huge spectroradiometry data sets and related sets of digital images from the field. Extensive opportunities are available for further work of this nature, as well as opportunities for participation in research on color polymorphism genetics, behavioral studies of mate choice and investigation of correlates of male coloration. So far, students have made or participated in six conference presentations arising from the telmatherinid research. I will be working on the first manuscript from this project during my sabbatical this fall. I anticipate two student co-authors.