Behavioral Ecology: My primary research interests are in sexual selection, the evolution of alternative reproductive tactics, and the evolution of communication in aggressive interactions. I primarily work with a group of freshwater fishes from Mexico, the swordtails and platyfishes (Xiphophorus). Currently we are examining variation in female mating preferences and the evolution of alternative reproductive tactics in X. multilineatus and its close relatives. We observe behavior in the field, and we also bring fish back to the laboratory to breed and observe. In addition, we use molecular techniques to examine gene flow, conduct paternity analyses and estimate phlogenetic relationships among populations and species. The phylogenetic trees we construct allow us to examine the evolution of behaviors and morphology across species, and test hypotheses about the evolution of female preferences and male-male aggressive behaviors, as well as role that preference and alternative tactics has played in the evolution of these species.

I currently have two research interests related to diabetes:
1) I am interested in investigating the relationship between fluctuating asymmetry in finger fingerprints and the propensity to develop diabetes. 2) I am also interested in determining the extent to which an alternative growth strategy we detected in the swordtail fish Xiphophorus mulitlineatus could become a model to understand variation in the MC4R gene in relation to diabetes.

Complete Curriculum Vitae (PDF)

Selected Publications

• Morris, M. R. Rios-Cardenas, O. S. Lyons, M. S. Tudor, and Bono, L. (2012). Fluctuating asymmetry indicates optimization of growth rate over developmental stability. Functional Ecology 26:723-731.

• Bono, L.M., Rios-Cardenas, O. and Morris, M. R. (2011). Alternative life history strategies in Xiphophorus multilineatus: Evidence for different ages to sexual maturity but not growth rates in the wild. Journal of Fish Biology 78, 1311

• Morris, M. R.,Brewer, J. and Rios-Cardenas, O. (2010). Variation in mating preference within a wild population influences the mating success of alternative mating strategies. Animal Behaviour 79, 673-678.

• Tudor, M. S. and Morris, M. R (2009) Does male mate preference in the swordtail Xiphophorus malinche influence variation in female preference for symmetry?  Behaviour 146:727-740.

• Tudor, M. S. and Morris, M. R. (2009) Experience plays a role in female preference for symmetry in the swordtail fish Xiphophorus malinche. Ethology 115, 812-822.

• Morris, M. R., Rios-Cardenas, O. and Darrah, A. (2008) Male mating tactics in the Northern Mountain Swordtail fish (Xiphophorus nezahualcoyotl): coaxing and coercing females to mate. Ethology 114:977-988.

• Fernandez, A. A. and Morris, M. R. (2008) Mate choice for more melanin as a mechanism to maintain a functional oncogene. Proceedings of the National Academy of Science, 105, 13503-13507.

• Gerl, E.J. and Morris, M.R. (2008) The Causes and Consequences of Color Vision. Evolution: Education and Outreach 1, 476-486.

For more publications please link to PubMed.

Awards and Honors

3/06 - 8/11     Associate Editor Behaviour
8/06 - 8/10     President Animal Behavior Society
6/02 - 8/05     Secretary Animal Behavior Society

Related Links

Biological Sciences
Morris Laboratory