Mary Caswell Stoddard
Junior Fellow in the Harvard Society of Fellows
2013 L'Oréal USA For Women In Science Fellow
View my CV here.
I am an evolutionary biologist with broad interests in avian vision and coloration, brood parasitism and coevolution, and the evolution and development of avian eggs. I use a multidisciplinary approach – involving computer science, mathematics, and engineering – to explore key questions in evolutionary biology.
Interested undergraduates are welcome to contact me to discuss research projects and opportunities.
In 2008, I received my undergraduate degree from Yale University, where I researched avian vision and plumage color evolution at the Peabody Museum of Natural History. I received a Marshall Scholarship and an NSF Graduate Research Fellowship to study at the University of Cambridge, where I completed my PhD research in 2012. In Cambridge, I was a member of Gonville and Caius College.
Bird vision and coloration
Birds are among the most colorful organisms in nature. In addition, they possess an ancient and sophisticated visual system that differs dramatically from our own. Unlike humans, birds have a fourth color cone in their retinas that is sensitive to ultraviolet wavelengths. Most diurnal birds thus appear to be tetrachromatic (four color cone-types), compared to trichromatic humans.
I am interested in using models of avian color perception to understand the evolution and diversity of plumage coloration. How colorful are birds, from the avian visual perspective? What constrains the evolution of plumage coloration? What roles have pigmentary and structural colors played in the evolution of the avian plumage palette? To investigate these questions, I use a quantitative model of avian tetrahedral color space – for which I developed the TETRACOLORSPACE computer program, see below – to describe phylogenetic patterns of color evolution both in smaller clades (e.g., New World buntings) and at broader taxonomic scales.
Avian brood parasites
The Common Cuckoo(Cuculus canorus) is a notorious brood parasite that sneaks its eggs into the nests of other species. I am investigating the visual signals involved in Cuckoo egg mimicry, particularly with respect to egg color and pattern. With collaborators at the University of Cambridge, I have been developing new computational tools for analyzing egg visual signals as seen by birds.
Evolution and engineering of avian eggs
I am interested in the mechanistic and functional basis of avian egg diversity. With collaborators at Harvard, Cambridge, and Oxford, I am investigating genomic, physiological, and structural aspects of avian egg evolution. This research combines theoretical modeling with empirical work in the lab and field, and in particular makes use of the extraordinary egg and nest collections of the Harvard Museum of Comparative Zoology.
The visual systems of birds, many other reptiles, and many fish include four color-sensitive retinal cone-types. As a consequence, their color vision is more complex than human color vision. In collaboration with Richard Prum, I developed a new computational tool – based on a well-described tetrahedral color space model (Goldsmith 1990; Endler and Mielke 2005) – that allows users to model visual color stimuli for these tetrahedral visual systems.
TETRACOLORSPACE is a computer program developed for the tetrahedral analysis of colors measured from reflectance spectra or from four cone stimulus values, using MATLAB 7 software (MathWorks, Natick, MA). TETRACOLORSPACE can analyze colors based on ultraviolet or violet cone-type avian visual systems, or can use cone-sensitivity functions input by the user. TETRACOLORSPACE provides an assortment of quantitative analyses and graphical tools for describing color stimulus variation and diversity. Details are available in Stoddard and Prum (2008).
TETRACOLORSPACE is provided for free here, and the manual is available here. When using the program, please cite the original publication:
Note that Allison Shultz has implemented several TETRACOLORSPACE analyses in R, the details of which can be found here.
Johnstone, R., A. Manica, A. Fayet, M. C. Stoddard, M. Rodríguez-Gironés, C. Hinde. Reciprocity, turn-taking and conditional cooperation between great tit parents. Behavioral Ecology. In Press.
Hanley, D., M. C. Stoddard, P. Cassey, and P. Brennan. 2013. Eggshell conspicuousness in ground nesting birds: do conspicuous eggshells signal nest location to conspecifics? Avian Biology Research 6: 147-156.
Stoddard, M. C., and R. M. Kilner. 2013. The past, present and future of ‘cuckoos versus reed warblers’. Animal Behaviour. pdf
Stournaras, K. E., E. Lo, K. Böhning-Gaese, E. Cazetta, D. M.Dehling, M. Schleuning, M. C. Stoddard, M. J. Donoghue, R. O. Prum, and H. M. Schaefer. 2013. How colorful are fruits? Limited color diversity in fleshy fruits on local and global scales. New Phytologist. pdf
Mendes-Pinto, M. M., A. M. LaFountain, M. C. Stoddard, R. O. Prum, H. A. Frank, and B. Robert. 2012. Variation in carotenoid-protein interaction in bird feathers produces novel plumage coloration. Journal of The Royal Society Interface. pdf
Prum, R.O., A. Fountain, J. Berro, M. C. Stoddard, and H. Frank. 2012. Molecular diversity, metabolic transformation, and evolution of carotenoid feather pigments in cotingas (Aves: Cotingidae). Journal of Comparative Physiology B. pdf
Stoddard, M. C. 2012. Mimicry and masquerade from the avian visual perspective. Current Zoology 58: 630-648. pdf
Stoddard M. C., A. Fayet, R. M. Kilner, and C. Hinde. 2012. Egg speckling patterns do not advertise offspring quality or influence male provisioning in great tits. PLoS ONE 7: e40211. pdf
Stoddard, M. C., K. Marshall, and R. M. Kilner. 2011.Imperfectly camouflaged avian eggs: artefact or adaptation? Avian Biology Research 4: 196-213. pdf
Stoddard, M. C., and R. O. Prum. 2011. How colorful are birds? Evolution of the avian plumage color gamut. Behavioral Ecology 22: 1042-1052. pdf
Stoddard, M. C., and M. Stevens. 2011. Avian vision and the evolution of egg color mimicry in the common cuckoo. Evolution 65: 2004-2013. pdf
Stoddard, M. C., and M. Stevens. 2010. Pattern mimicry of host eggs by the common cuckoo, as seen through a bird’s eye. Proceedings of the Royal Society, Series B 277: 1387-93. Covered by BBC News Big Picture and the New York Times. pdf
Stevens, M., M. C. Stoddard, and J.P. Higham. 2009. Studying primate color: towards visual system-dependent methods. International Journal of Primatology 30: 893–917. pdf
Stoddard, M. C., and R. O. Prum. 2008. Evolution of avian plumage color in a tetrahedral color space: a phylogenetic analysis of New World buntings. American Naturalist 171: 755–776. pdf
Ellis, J. C., M. C. Stoddard, and L. W. Clark. 2008. Breeding by a lesser black-backed gull (Larus fuscus) on the Atlantic coast of North America. North American Birds 61: 546-548. pdf
PDFs are for personal use only.