I am an evolutionary biologist, and my long-term research vision is to incorporate a broad scope of disciplines to understand the genetic basis of phenotypic evolution at the macroevolutionary scale.
developmental basis of chemosensory diversity
As an NSF postdoctoral fellow in the Bhullar lab at Yale University, I am investigating the evolutionary origins of sensory brain regions and nasal morphologies. Through comparative embryology, I am using innovative staining and imaging technologies to visualize and quantify the similarities and differences in the development of chemosensory morphological structures.
Molecular evolution of olfactory receptors in Leaf-Nosed Bats
Do you smell what you smell because of what you eat? This study illuminates how the olfactory receptor evolution may have opened up novel dietary niches for bats. New World Leaf-nosed bats (Phyllostomidae) occupy an enormous range of dietary niches and natural selection has shaped an array of morphological and sensory adaptations to exploit these dietary niches. However, the molecular mechanisms that allowed populations to depart from their ancestral insectivorous diet and detect novel resources, such as nectar or fruit, are unknown. Phyllostomids need to find these resources while flying in the dark. Behavioral evidence has shown the sense of smell is a critical supplement to echolocation for detecting food in a cluttered environment, but can we detect these signatures of dietary adaptation in olfactory receptor genes. I hypothesize that the genetic machinery governing the detection of plant volatiles to also be shaped by natural selection. Using transcriptomes from the main olfactory epithelium, I am sequencing the olfactory receptor profiles in over dozens of phyllostomid species with divergent diets. An exciting aspect of this project is the development of gene duplication models to better characterize adaptation in olfactory receptors, the largest multigene family in the mammalian genome.
MACROEVOLUTION AND ADAPTIVE RADIATION OF BABBLERS
Birds of the family Timaliidae (babblers), are a species-rich group of passerines distributed throughout the Old World characterized by distinct phenotypic differences and highly diverse morphological features, including highly variable body size, bill structure,and plumage patterns. The evolutionary relationships among babblers have puzzled biologists for decades and the family is under constant revision. Although widely distributed, closely related species often coexist, suggesting niche partitioning among close relatives. The high morphological diversity may indicate a variety of niches being exploited by this family and may be a result of ecological opportunity. Because similar species can exist together in the same geographic location, intraspecific competition may have forced these birds to occupy other niches and eventual diversification to prevent competitive exclusion.High variation in morphological traits that provide higher fitness in a niche and rapid divergence from a common ancestor are features often used to diagnose an adaptive radiation, but frequently are poorly quantified. Rather than labeling the divergence of babblers as an adaptive radiation after-the-fact, we hypothesize the diversification of several subfamilies and genera within babblers as adaptive radiations by quantitatively analyzing the evolution and persistence of morphological traits related to fitness.