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(* indicates undergraduate coauthor)
Johnson, M. A., L. J. Revell, and J. B. Losos. In review. Behavioral convergence and adaptive radiation: effects of habitat use on territorial behavior in Anolis lizards.
Sanger, T. J., P. M. Hime, M. A. Johnson, J. Diani, and J. B. Losos. 2008. Laboratory protocols for husbandry and embryo collection of Anolis lizards. Herpetological Review 39:58-63. PDF
Johnson, M. A., M. Leal, L. R. Schettino, A. C. Lara, L. J. Revell, and J. B. Losos. 2008. A phylogenetic perspective on foraging mode evolution in West Indian Anolis lizards. Animal Behavior 75:555-563. PDF
Revell, L. J., M. A. Johnson, J. A. Schulte, II, J. J. Kolbe, and J. B. Losos. 2007. A phylogenetic test for adaptive convergence in rock-dwelling lizards. Evolution 61:2898-2912. PDF
Singhal, S.*, M. A. Johnson, and J. T. Ladner*. 2007. The behavioral ecology of sleep: natural sleeping site choice in three Anolis lizard species. Behaviour. 144: 1033-1052. PDF
Glor, R. E., M. A. Johnson, and A. Larson. 2007. Polymorphic microsatellite loci for the Puerto Rican crested anole (Anolis cristatellus) and their amplification in related Puerto Rican species. Conservation Genetics. 8:1491-1493. PDF
Johnson, M. A., R. Kirby*, S. Wang*, and J. B. Losos. 2006. What drives habitat use by Anolis lizards: habitat availability or selectivity? Canadian Journal of Zoology 84: 877-886. PDF
Johnson, M. A. 2005. A new method of temporarily marking lizards. Herpetological Review 36:277-279. PDF
Browne, R. A., D. J. Anderson, M. D. White, and M. A. Johnson. 2003. Genetic varation of Opuntia cactus species of the Galápagos Islands and coastal Ecuador. Noticias de Galápagos 62:11-15. PDF
In my current work, I’m studying the relationship between sexual dimorphisms (i.e., how males and females differ) in reproductive morphology with dimorphisms in reproductive behavior. The Wade lab and others have established Anolis carolinensis as a model organism for investigating differences between the sexes in brain, morphology, and behavior, especially in traits important for courtship and copulation. For Anolis lizards, the dewlap, a colorful throat fan extended during courtship and territorial defense, is an important structure for reproductive behavior. Anolis carolinensis males have large dewlaps, while females have very small dewlaps. The focus of my current work is a comparison of this highly dimorphic model species with other species in which males and females have similarly sized dewlaps (one species in which both sexes have large dewlaps, and one species in which males and females have diminutive dewlaps) and close relatives of these species that exhibit high sexual dimorphism. I am currently measuring traits such as muscle fiber size, motoneuron soma size, and levels of androgens and their receptors in the brain in nine species of Carribean anoles. This work will lead to a comparative analysis of the evolution of reproductive behavior and the mechanisms underlying it.