Name: Dr. Darcy B Kelley

Position: Professor of Biology

Research Description:

Social communication is ubiquitous in animals; even the most solitary species meet to mate. Dedicated sensory, neural and muscular systems support social communication and determining how these systems work illuminates how one brain communicates with another.

Our goal is to determine how the nervous system produces and responds to social signals and to identify – across evolutionary timescales – the genetic changes that support the emergence of species differences in courtship communication. We study vocal communication specifically because this form of behavioral is readily described - and differences quantified - using acoustic analyses of sounds. We study African clawed frogs, Xenopus, because their social communication is dominated by vocal signaling.  Females sing to males, males to females and to other males and these signals are specific to the sex of the signaler, the recipient and the social context. The genus – derived from terrestrial ancestors – is now entirely aquatic and includes 29 described species; each can be identified by specific, heritable features of male advertisement calls. Females are most sensitive to the acoustic features of male vocal signals from their own species.

The return to water from land in ancestral Xenopus, was accompanied by a novel means of vocal production still using the larynx but not requiring airflow and vocal cords. The male larynx is tuned to produce spectral features that contribute to unique vocal signatures of each species.  The pattern of sound pulses that distinguish different species is produced by a specific neural circuit in the hindbrain., an ancient exaptation of hindbrain breathing circuits shared by all terrestrial vertebrates, including humans. Differences in vocal patterns between species have been mapped to key components of this hindbrain circuit.

Our current research aims to identify genomic loci associated with species specific vocal pattern production and perception using a genome-wide association approach and inter-fertile hybrids between relatively recently diverged Xenopus species: laevis, petersii, victorianus and poweri.

Lab Memberships

Kelley Lab (Principal Investigator/Director)

Contact Information

Address:
Department of Biological Sciences
Columbia University
MC 2432
913 Fairchild Center, MC 2432
New York, NY
10027, USA

Web Page: http://www.columbia.edu/cu/biology/faculty/kelley/
Phone:  212-854-4939