Mattie Squire
Ph.D. Student

Mattie Squire

Department of Biology
Texas A&M University 

3258 TAMU
College Station, TX 77843 

Tel: 979.845.3614 

email:msquire AT 

Curriculum Vitae (updated August 2007)

Mattie Squire


M.S. student, Biology – Fall 2011-Present Texas A&M University, College Station, Texas Advisor: Gil Rosenthal

B.S., Biology –2010 Cum laude Oregon State University, Corvallis, Oregon

General Research Interests

Mechanisms of pre- and post-copulatory sexual selection (especially in regards to sperm competition and cryptic female choice), sexual conflict, evolution of mating systems, evolution of behavior; I am also broadly interested in the roles each of these concepts play in the formation and maintenance of species.

Past Research

I graduated from Oregon State University with a Bachelor’s of Science in Biology (2010). During my time there, I assisted with research regarding postcopulatory sexual selection (mainly sperm competition) and sexual conflict in Thamnophis sirtalis (red-sided garter snake) with Dr. Robert Mason and his graduate students (mainly Dr. Chris Friesen).

Current Research

I joined the Rosenthal lab in the summer of 2011 to continue studying topics related to sexual selection, as well as mate choice and its consequences, this time in a hybrid zone.

Hybridization represents a collision of genomes that can introduce new genetic and phenotypic variation into a population. Depending on the environment, this may lead to increased individual fitness and allow for integration of novel gene combinations via gene flow between divergent species Recent work also shows that hybridization is an important evolutionary process in terms of the diversification of species and that it is probably far more common than once thought To further understand the process of hybridization, studies examining mating decisions can be used to predict not only how hybridization occurs in the first place but also to predict the future evolutionary path of parental and hybrid populations.

For my Master’s thesis, I conducted studies on Xiphophorus malinche, X. birchmanni, and their hybrids. I examine the chemical and visual preferences of male X. malinche with dichotomous choice trials; I found that, unlike females or male X. birchmanni, male X. malinche show no strong preferences in terms of chemical or visual cues. The presence or absence of male preferences, in addition to female preferences and other factors, is key to understanding the mating system and future of a population. My work here allowed us to complete the innate “preference picture” of the X.s malinche/ X. birchmanni hybrid system. In another study, I used microsatellite markers to determine that there is a high degree of polyandry in a subpopulation of an X. malinche and X. birchmanni hybrid zone. As multiple paternity can affect both the nature and direction of sexual selection, this study will serve as important ground work for similar studies in other hybrid zones as well as for future studies that further investigate sexual selection in this system in general.

When not at the lab or teaching, I enjoy drawing, reading comic books, long walks in the woods (or the on occasional beach), birding, drinking west coast microbrews and wine, and catching herptofauna.


  1. M. Schumer, D.L. Powell, P.J. Delclos, M. Squire, R. Cui, P. Andolfatto and G.G. Rosenthal, 2017. Assortative mating and persistent reproductive isolation in hybrids. PNAS. doi: 10.1073/pnas.1711238114 [PDF]