Evolution and Neurobiology of Communication

Communication is an essential part of sociality, and an animal’s vocal communications provide a window into their cognitive capabilities, motivations, and behavioral ecology.  Communication is also a important model of sensorimotor neurobiology because vocalizations are the motor output of a sophisticated suite of brain pathways that integrate across multiple sensory modalities and time scales. Vocal communication systems are highly diverse because they have been shaped by intense natural and sexual selection. Studying the evolution of communication networks in the brain provides important insight into how environment and ecology molded the social brain.

Our lab studies bats because of their biosonar capabilities and their unusually broad repertoire of communication calls and songs.

Echolocation provides an exciting model system for exploring how multiple brain pathways interact to control behavior on a millisecond time scale.  Our neural studies investigate the neurocircuits that guide delicate changes in sonar pulse acoustics.  Our behavioral studies of bats echolocating in groups has shed light on how they coordinate their sonar systems to minimize interference with one another.  This research has direct relevance to man-made sonar and wireless communications systems.

Singing by bats offers exiting new opportunities to young investigators to explore how mammals and birds converged upon a similar behavior via different neural mechanisms. Identifying and characterizing the functional neurocircuitry of the bat’s song production network is a major component of our research.

Graduate student opportunities.  Students interested in pursuing the neuroethology of communication are encouraged to apply to our graduate training programs in Biology, Neuroscience or Ecology and Evolutionary Biology. Contact Dr. Smotherman directly for more information.

1. Macias, S, Bakshi, K, Troyer, T, Smotherman, M. The prefrontal cortex of the Mexican free-tailed bat is more selective to communication calls than primary auditory cortex. J Neurophysiol. 2022;128 (3):634-648. doi: 10.1152/jn.00436.2021. PubMed PMID:35975923 PubMed Central PMC9448334.
2. Smarsh, GC, Long, AM, Smotherman, M. Singing strategies are linked to perch use on foraging territories in heart-nosed bats. Ecol Evol. 2022;12 (2):e8519. doi: 10.1002/ece3.8519. PubMed PMID:35169446 PubMed Central PMC8837579.
3. Macias, S, Bakshi, K, Smotherman, M. Faster Repetition Rate Sharpens the Cortical Representation of Echo Streams in Echolocating Bats. eNeuro. 2022;9 (1):. doi: 10.1523/ENEURO.0410-21.2021. PubMed PMID:34903526 PubMed Central PMC8856701.
4. Brokaw, AF, Davis, E, Page, RA, Smotherman, M. Flying bats use serial sampling to locate odour sources. Biol Lett. 2021;17 (10):20210430. doi: 10.1098/rsbl.2021.0430. PubMed PMID:34665992 PubMed Central PMC8526173.
5. Brokaw, AF, Smotherman, M. Olfactory tracking strategies in a neotropical fruit bat. J Exp Biol. 2021;224 (Pt 4):. doi: 10.1242/jeb.231829. PubMed PMID:33536298 PubMed Central PMC7904095.
6. Macias, S, Bakshi, K, Garcia-Rosales, F, Hechavarria, JC, Smotherman, M. Temporal coding of echo spectral shape in the bat auditory cortex. PLoS Biol. 2020;18 (11):e3000831. doi: 10.1371/journal.pbio.3000831. PubMed PMID:33170833 PubMed Central PMC7678962.
7. Macias, S, Bakshi, K, Smotherman, M. Functional organization of the primary auditory cortex of the free-tailed bat Tadarida brasiliensis. J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2020;206 (3):429-440. doi: 10.1007/s00359-020-01406-w. PubMed PMID:32036404 .
8. Brokaw, AF, Smotherman, M. Role of ecology in shaping external nasal morphology in bats and implications for olfactory tracking. PLoS One. 2020;15 (1):e0226689. doi: 10.1371/journal.pone.0226689. PubMed PMID:31914127 PubMed Central PMC6948747.
9. Macias, S, Bakshi, K, Smotherman, M. Laminar Organization of FM Direction Selectivity in the Primary Auditory Cortex of the Free-Tailed Bat. Front Neural Circuits. 2019;13 :76. doi: 10.3389/fncir.2019.00076. PubMed PMID:31827425 PubMed Central PMC6890848.
10. Smotherman, M, Bakshi, K. Forward masking enhances the auditory brainstem response in the free-tailed bat, Tadarida brasiliensis, during a critical time window for sonar reception. J Acoust Soc Am. 2019;145 (1):EL19. doi: 10.1121/1.5087278. PubMed PMID:30710968 .