Dr. Day is a neuroscientist who conducts research centered on understanding the evolution and function of brain regions involved in spatial and motor learning, primarily in birds.
Research Interests
Dr. Day's interests are fairly broad but are centered on understanding the evolution, function, and neuroendocrinology of brain regions involved in spatial and motor learning, principally the hippocampus and cerebellum. Currently, she is involved in several projects that revolve around steroid induced neuroplasticity in the avian cerebellum.
Dr. Day maintains an interest in non-avian vertebrate models as well. She welcomes inquiries from potential graduate students and dedicated undergraduates that have an interest in her research or related projects in behavioral neuroscience.
Publications
Acrobatic display behaviour is sexually selected in manakins (Pipridae) and can place high demands on many neural systems. Manakin displays vary across species in terms of behavioural complexity, differing in number of unique motor elements, production of mechanical sounds, cooperation between displaying males, and construction of the display site. Historically, research emphasis has been placed on neurological specializations for vocal aspects of courtship, and less is known about the control of physical, non-vocal displays. By examining brain evolution in relation to extreme acrobatic feats such as manakin displays, we can vastly expand our knowledge of how sexual selection acts on motor behaviour. We tested the hypothesis that sexual selection for complex motor displays has selected for larger brains across the Pipridae. We found that display complexity positively predicts relative brain weight (adjusted for body size) after controlling for phylogeny in 12 manakin species and a closely related flycatcher. This evidence suggests that brain size has evolved in response to sexual selection to facilitate aspects of display such as motor, sensorimotor, perceptual, and cognitive abilities. We show, for the first time, that sexual selection for acrobatic motor behaviour can drive brain size evolution in avian species and, in particular, a family of suboscine birds.
Fuxjager, M. J., Eaton, J., Lindsay, W. R., Salwiczek, L. H., Rensel, M. A., Barske, J., Sorenson, L., Day, L. B. and Schlinger, B. A. (2015). Evolutionary patterns of adaptive acrobatics and physical performance predict expression profiles of androgen receptor – but not oestrogen receptor – in the forelimb musculature. Functional Ecology, 29: 1197–1208.
Schlinger, B. A., Barske, J., Day, L.B, Fusani, L., & Fuxjager, M. J. (2013). Hormones and the neuromuscular control of courtship in the golden-collared manakin (Manacus vitellinus). Frontiers in Neuroendocrinology, 34(3), 143–56.
Fuxjager, M. J., Barske, J., Du, S., Day, L. B., & Schlinger, B. A. (2012). Androgens Regulate Gene Expression in Avian Skeletal Muscles. PLoS ONE, 7(12).
Day, L. B., Fusani, L., Kim, C., & Schlinger, B. a. (2011). Sexually Dimorphic Neural Phenotypes in Golden-Collared Manakins (Manacus vitellinus); Brain, Behavior and Evolution, 77(3), 206–218.
Day, L. B., Guerra, M., Schlinger, B. A., & Rothstein, S. I. (2008). Sex differences in the effects of captivity on hippocampus size in brown-headed cowbirds (Molothrus ater obscurus). Behavioral Neuroscience, 122(3), 527–34.
