Peer Reviewed Journals

  • Folwell, M., Sanders, K., Brennan, P.L.R., and J. Crowe-Riddell. 2022. First evidence of hemiclitores in snakes. Proc. Royal Soc. B. 289: 20221702. https://doi.org/10.1098/rspb.2022.1702.

  • Orr, T., Lukistch, T., Eiting, T., and P.L.R. Brennan. 2022. Testing morphological relationships in between female and male copulatory structures in bats. Integrative and Comparative Biology. 62: 602-612

  • Greenwood, J., Lara Granados, G. Secor, S. Brian, T., Showalter, I., Hedrick, B. and P.L.R. Brennan. 2022. Divergent genital morphologies and female-male covariation in watersnakes. Integrative and Comparative Biology. 62: 569-580. https://doi.org/10.1093/icb/icac020

  • Brennan, P.L.R. 2022. Evolution and Morphology of female genitalia in Amniotes. Integrative and Comparative Biology. 62: 521-532.

  • Poo, S., Whitfield, S., Watkins-Colwell, G., Gil, N., Goodwin, J, Brennan, P.L.R., … Chakrabarthi, P. 2022. Bridging the research gap between live collections in zoos and preserved collections in natural history museums. Bioscience. doi:10.1093/biosci/biac022.

  • Lara Granados, G. Greenwood, J. Secor, S. Hedrick, B. and P.L.R. Brennan. 2022. 3-D examination of the genital morphology of male and female diamond watersnakes Nerodia rhombipher. Biological Journal of the Linnean Society. 10.1093/biolinnean/blac051

  • Brennan, P.L.R., Cowart, J. and D. O. Orbach. 2022. Functional morphology of the dolphin clitoris. Current Biology. 31: R1-R3.*

  • Brennan, P.L.R., Sterett, M., DiBuono, M., Lara Granados, G. Klo, K., Marsden, R., Schleinig, P., Tanner, L. and S. Purdy. 2021. Intra-horn penile intromission in the alpaca and consequences to genital morphology. Integrative and Comparative Biology. DOI: 10.1093/icb/icab050, pp:1-10.

  • Brennan, P.L.R. and Orbach, D. O. 2021. Postcopulatory sexual selection. Oxford Bibliographies. DOI: 10.1093/OBO/9780199941728-0131.

  • Orbach, D.O. Brassey, C. Gardiner, J and Brennan, P.L.R. 2021. 3D Genital Shape Complexity in Female Marine Mammals. Ecology and Evolution. DOI: 10.1002/ece3.7269. (5)

  • Brennan, P.L.R. and Orbach, D.N. 2020. Copulatory behavior and its relationship to genital morphology. Advances in the Study of Animal Behavior. 52: 65-122.

  • Hedrick, B. Antalek-Schrag, P. Conith A. J. Natanson, L. J. Brennan, P. L. R. 2019. Variability and asymmetry in the shape of the Spiny Dogfish vagina revealed by 2D and 3D geometric morphometrics. Journal of Zoology. doi:10.1111/jzo.12653.

  • Orbach, D. Rattan, S. Hogan, M. Crosby, A. Brennan, P.L.R. 2019. Biomechanical  Properties of Female Dolphin Reproductive Tissue. Acta Biomateralia.    https://doi.org/10.1016/j.actbio.2019.01.012.

  • Delmore, J*., Brennan P.L.R. and Orr. T. 2018. Reproductive melanization may protect sperm from harmful UV radiation. Ecology and Evolution, 32: 127-139 *Undergraduate co-author.

  • Orbach, D. Hedrick, B. Würsig, B., Mesnick, S. L., Brennan, P.L.R. 2017. The Evolution of Vaginal Shape Variation in Cetaceans. Evolution. doi: 10.1111/evo.13395.

  • Orbach, D., Kelly, D., Solano, M., and Brennan, P.L.R. 2017. Genital Interactions During Simulated Copulation Amongst Marine Mammals. Proc. Royal Soc. B. 284: 20171265. *Press coverage.

  • Brennan, P.L.R., Gereg, I., Goodman, M. Feng, D. and Prum, R.O. 2017. Evidence of socially induced phenotypic plasticity of penis morphology and delayed reproductive maturation in waterfowl. The Auk. 134. DOI: 10.1642/AUK-17-114.1. *Press coverage.

  • Hanley, D., Šulc, M., Brennan, P. L. R., Hauber, M. E., Grim, T. and Honza, M. 2016. Dynamic Egg color mimicry. Ecology and Evolution. doi: 10.1002/ece3.2187.

  • Brennan, P.L.R. 2016. The role of genital coevolution in intromittent organ morphology. Journal of Integrative and Comparative Biology. doi:10.1093/icb/icw018.

  • Orr, T. and Brennan, P.L.R. 2016. All features great and small: The role of the baculum and penile spines in mammals. Journal of Integrative and Comparative Biology. doi:10.1093/icb/icw057.

  • Friesen, C., Uhrig, E. J., Mason, R. and P.L.R. Brennan. 2016. Female resistence affects copulation duration, copulatory plug mass and sperm transfer in Red-sided garter snakes. J. Evolutionary Biology. 29: 952-964. doi: 10.1111/jeb.12836.

  • Brennan, P.L.R. 2016. Evolution: One Penis after All.  Current Biology. 26:29-31.

  •  Verdes, A., Cho, W., Hossain, M., Brennan, P.L.R, Hanley D., Grim, T. Hauber M.E., Holford,, M. 2015. Nature’s Palette: Characterization of Shared Pigments in Colourful Avian and Mollusk Shells. PLoS ONE. 10(12), e0143545.

  •  Orr, T. and Brennan, P.L.R. 2015. Sperm storage: distinguishing selective processes and evaluating criteria. Trends in Ecology & Evolution. 30: 261-272.

  • Orr, T and Brennan, P.L.R. 2015. Sperm storage across multiple scales–a reply to Marques, Garcia, and Ames. Trends in Ecology & Evolution, 20, 1-2.

  • Brennan, P.L.R. 2015. The promise and business of biomimicry. Book Review. BioScience. 10.1093/biosci/biv023.

  • Igic, B., Fecheyr-Lippens, D., Chan, A., Hanley, D., Brennan P.L.R., Grim, T., Waterhouse, G., Hauber, M.E., and Shawkey, M. 2014. A nanostructural basis for gloss on avian eggshells. J. Royal Soc. Interface. DOI:10.1098/rsif.2014.1210

  • Brennan, P.L.R., and Atkins-Regan, E. 2014. Endocrine regulation and sexual differentiation of avian copulatory sexually selected characters. Neuroscience and Biobehavioral Reviews. DOI: 10.1016/j.neubiorev.2014.08.010.

  • Brennan, P.L.R., Clark, R. and D. Mock. 2014. Time to step up: defending basic science and animal behaviour.  Animal Behaviour. 94: 101-105. *Press coverage below.

  • Brennan, P. L.R., Irschick, D., Johnson, N. C. Albertson. 2014.  Oddball science: Why funding studies of unusual evolutionary phenomena is crucial. BioScience. 64: 178-179 .* Press coverage below.

  • Herrera, A., Brennan, P. L.R. and M. Cohn. 2014. Development of avian external genitalia: interspecific differences and sexual differentiation of the male and female phallus. Sexual Development. DOI: 10.1159/000364927.

  • Brennan, P.L.R. 2014. Darwin in the bedroom: Evolution and Human Sexual Behavior. Book review. TREE. 29: 136-137.

  • Friesen, C., Uhrig, E. J., Squire, M. J., Mason, R. and P.L.R. Brennan. 2014. Sexual conflict over mating in red-sided Garter snakes (Thamnophis sirtalis) as evidenced by experimental manipulation of genitalia. Proc. Royal Society B. 281: 20132694. Press coverage below.

  • Showalter, I*., Todd, B. and P.L.R. Brennan. 2014. Intraspecific and interspecific variation of the vagina in two species of water snakes. Biological Journal of the Linnean Society. 111: 183-191. *undergraduate student.

  • Brennan, P.L.R. 2013. Genital Evolution: Cock-a-Doodle-Don’t. Current Biology. 23: R523-525.

  • Hanley, D., Stoddard, M.C., Cassey, P. and P.L.R. Brennan. 2013. Eggshell conspicuousness in ground nesting birds: do conspicuous eggshells signal nest location to conspecifics? Avian Biology Research. 6: 1-10.

  • Irschick, D. Albertson, C. Brennan, P.L.R., Podos, J., Johnson, N., Patek, S. and E. Dumont. 2013. The mechanics of adaptive radiation: From genotype to resource use. TREE. http://dx.doi.org/10.1016/j.tree.2012.12.004

  • Brennan, P.L.R. 2012. Mixed paternity in Paleognathes despite exclusive male parental care. Animal Behavior. 84: 693-699.

  • Brennan, P.L.R., and Prum, R. 2012. Sexual conflict in the narrow sense: New insights from waterfowl biology. Philosophical transactions of the Royal Society. 367: 2324-2338.

  • Aidala, Z., Huynen, L. Brennan, P. L. R., Musser, J., Fidler, A. Chong, N., Machovsky, G. E., Anderson, M. G., Talaba, A., Lambert, D. and M. E. Hauber. 2012. Ultraviolet visual sensitivity in three avian lineages: paleognathes, parrots and passerines. Journal of Comparative Physiology A. 198: 495-510.

  • Brennan, P.L.R, and Prum, R. 2011. The erection mechanism of the ratite penis.  Journal of Zoology 286: 140-144. (press coverage of this research below).

  • Branislav I., M. E. Hauber, J. A. Galbraith, T. Grim, D. C. Dearborn, P.L.R. Brennan, C. Moskat, P. K. Choudhary, and P. Cassey. 2010. Comparison of micrometer- and scanning electron microscope-based measurements of avian eggshell thickness. J. Field Ornithology 81: 402–410.

  • Brennan, P.L.R. 2010. Sexual Selection. Nature Education Knowledge 1. (8):24. http://www.nature.com/scitable/knowledge/library/sexual-selection-13255240.

  • Brennan, P.L.R. 2010. Clutch predation in Great Tinamous and implications for the evolution of egg color. Journal of Avian Biology. 41: 1-8 (press coverage of this research below)

  • Brennan, P.L.R., Clark, C. and Prum, R. 2010. Explosive Eversion and Functional Morphology of Waterfowl Penis Supports Sexual Conflict in Genitalia. Proc. Royal Society B. 277(1686):1309-14. (Press coverage below). High-speed videos have been watched >600.000 times online.

  • Branislav, I., Cassey, P., Grim, T., Gill, B. J., Brennan, P.L.R., Moskat, C., Greenwood, D.R., Hauber, M.E. 2009. Detecting biliverdin from colourful eggshells of extinct birds. Chemoecology. Doi:10.1007/s00049-009-038-2.

  • Brennan, P.L.R. 2009. Incubation in Great Tinamous (Tinamus major). The Wilson Journal of Ornithology. 121 (3): 506-511.

  • Brennan, P.L.R., Birkhead, T., Zyskowski, K., Van der Waag, J. and Prum, R. O. 2008. Independent evolutionary reductions of the phallus in basal birds. Journal of Avian Biology. 39: 487-492.

  • Brennan, P.L.R. and Hyseni, C. 2008. Development of microsatellite markers for Great Tinamous (Tinamus major). Molecular Ecology Resources 8:933-935.

  • Brennan, P. L. R., Prum, R. O., McCracken, K. G., Sorenson, M. D., Wilson, R. E. and T. R. Birkhead. 2007. Coevolution of male and female genital morphology in waterfowl. PLoS ONE 2(5): e418. Doi:10.1371/journal.pone.0000418. Highest number of views of any avian paper published in the journal ->10,000- (press coverage below).

  • Brennan, P. 2004. Techniques for studying the behavioral ecology of forest-dwelling tinamous (tinamidae).  Ornitologia Neotropical 15 (Supp.): 329-337.

  • Pitman, R. L., Palacios, D. M., Brennan, P. L. R., Brennan, B. J., Balcomb, K. C. and Miyashita, T. 1999. Sightings and possible identity of a bottlenose whale in the tropical Indopacific: Indopacetus pacificus?. Marine Mammal Science. 15 (2): 531-549

  • Acevedo-Gutierrez, A., Brennan, B. J., Rodriguez, P. and Thomas, M. 1997.  Resightings and behavior of false killer whales (Pseudorca crassidens) in Costa Rica. Marine Mammal Science, 13 (2): 135-142.

    Book Chapters

  • Brennan, P.L.R. 2019. Bird with penises: Copulation mechanics and behavior. Encyclopedia  

     of Animal Behavior. Second Edition. Volume 4: 513-522. Elsevier.

  • Orr, T. and Brennan, P.L.R. 2017. Sperm storage and delayed fertilization. In: Encyclopedia of Reproduction. Volume 6. Comparative Reproduction, Female Reproduction. Second Edition. Oxford, UK. Elsevier.  https://doi.org/10.1016/B978-0-12-811899-3.20577-6

  • Brennan, P.L.R. 2017. The evolution of genitalia. In: Schakelford T and Weelkes-Schakelford V (Eds). Encyclopedia of Evolutionary Psychological Sciences. Springer.

  • Brennan, P. L.R. 2017. Male prudence and sperm limits. In: Schakelford T and Weelkes-Schakelford V (Eds). Encyclopedia of Evolutionary Psychological Sciences. Springer.

  • Brennan, P.L.R. 2016. Importance of basic science and evolutionary biology. In: Richard Kilman (Ed). Encyclopedia of Evolutionary Biology. Vol 1, pp 130-136. Oxford: Academic Press.

  • Brennan, P.L.R. and Prum, R.O. 2015. Mechanisms and Evidence of Genital coevolution: The roles of natural selection, mate choice and sexual conflict. In: Sexual Conflict. Rice W and Gavrilets, S. (Eds). Cold Spring Harbor Laboratory Press. 385-405pp. Biol 7:a017749

  • Brennan, P.L.R. and Prum, R.O. 2014. Mechanisms and Evidence of Genital coevolution: The roles of natural selection, mate choice and sexual conflict. In: Sexual Conflict. Rice W and Gavrilets, S. (Eds). Cold Spring Harbor Laboratory Press.

  • Bauer, E., Brennan P.L.R., and Brooks, D. 2014. Tinamous of Mexico. Chapter 10. In: Wildlife Ecology and Management in Mexico. R. Valdez and J.A. Ortega-S. (Eds). Texas A&M University Press. College Station TX.  Mexico.

    Popular Science

  •  Brennan, P.L.R. 2014. The hidden side of sex. The Scientist. July Issue. http://www.the-scientist.com/?articles.view/articleNo/40321/title/The-Hidden-Side-of-Sex/

  • Brennan, P.L.R. 2013. Why I study duck penises.  Guest blog published April 2/2013 at Slate.com.http://www.slate.com/articles/health_and_science/science/2013/04/duck_penis_controversy_nsf_is_right_to_fund_basic_research_that_conservatives.html. >1000 tweets, 4000 Facebook shares, >16000 Facebook Likes. (Press coverage below).