Dr. Michael Greenfield

Michael D. Greenfield is an American biologist born in 1952 in New York City and currently an Adjunct Professor of Ecology and Evolutionary Biology at the University of Kansas and a Professeur Invité in the Équipe Neuro-Ethologie Sensorielle at the Université de Lyon/Saint-Etienne in France.  He and his wife, Valery Terwilliger, are dual US / French citizens living in Tours, France.  Greenfield is best known for his work on insect communication, especially acoustic signaling and cognition.  His studies have emphasized integration of physiological, ecological and evolutionary principles, and have been conducted in the laboratory and field.  An objective pursued over many years has been understanding how and why specially timed group choruses, particularly those involving synchrony and entrainment of signaling rhythm, form in acoustic species.

Education

Michael Greenfield received his B.A. in biology from New York University in 1973 after having initially majored in (aero)engineering.  Passionate about natural history from an early age, he continued his education in biology at the University of Wisconsin, where he became interested in pheromone communication, a new field at that time.  In 1978 he was awarded a Ph.D. in entomology, under the direction of Michael Karandinos, for a thesis on community ecology approaches to studying reproductive isolation between species as afforded by pheromone communication channels.

Greenfield accepted a Smithsonian Postdoctoral Fellowship in 1978 to extend his thesis work by analyzing reproductive isolation in a species-rich tropical area, Panama, where the problem of maintaining a unique channel would be much greater.  The study was done at the Smithsonian Tropical Research Intitute (STRI), and it was there that he began a lifelong fascination with acoustic communication and chorusing phenomena, influenced to no small degree by A. Stanley Rand of the institute.  A second postdoctoral appointment at the University of Florida (1979-1981) allowed him to continue his research on pheromone and acoustic communication, there influenced strongly by Thomas J. Walker, and it was during this period that he reported the first finding of acoustic mating communication – by means of ultrasound – in the Lepidoptera.

Career

In 1981 Greenfield joined the Biology Department at the University of California, Los Angeles as an assistant professor, and was promoted to associate professor in 1987. He later moved to the Department of Entomology at the University of Kansas in 1991, was promoted to full professor in 1993, and served as department chair from 1995-1999.  Owing to departmental mergers, beginning in 2000 his appointment was transferred to the Department of Ecology and Evolutionary Biology.  Greenfield took sabbatical leaves during these years, 1989 at the Hebrew University of Jerusalem (Israel) and 1999-2000 at the Department of Neuroscience, University of Arizona.  He used this second sabbatical year to author the book ‘Signalers and Receivers: Mechanisms and Evolution of Arthropod Communication’ (Oxford University Press, 2002). From 2002-2004 he served as Program Director for Animal Behavior at the U.S. National Science Foundation.

In 2006 Greenfield moved to the Université de Tours (France), where he was appointed as a Professeur des Universités (Neuroscience) with affiliation as a Chercheur at the CNRS Insitut de la Recherche sur la  Biologie de l’Insecte (IRBI).  At the institute he was team leader for the Cognitive Ecology group, and was promoted to Professeur des Universités Classe Exceptionnelle in 2014.  He retired from his university post in Tours in 2017, but continues his teaching, research and writing as an affiliate of the University of Kansas in the US and the Université de Lyon/Saint Etienne in France.         

Chorusing, synchrony and entrainment

Greenfield’s work on acoustic insects showed the importance of rhythm and call timing in sexual selection – both mate choice and male-male competition.  He explained how finely-tuned female preferences for male calls that precede their neighbors by a brief interval can select for male call timing protocols by which an imperfect synchrony emerges as an epiphenomenon in some species, but in other species generates the emergence of anti-synchrony (call alternation between neighbors).  In yet other species synchrony per se is selected for, and call timing protocols that generate strict, in some cases ‘perfect’, synchrony are found. The work leading to the discoveries on call timing was largely possible because of advances in digital signal processing and computing ca. 1990 allowing elaborate testing of animal acoustic communication in the field.  With this ability Greenfield’s laboratory was able to make a series of discoveries on ultrasound communication in insects and on responses to the ‘auditory scene’ – the combined presence of conspecific (mating) signals and of predator (insectivorous bats) sounds.  The same digital signal processing was also adapted for the study of signal rhythm, and responses to signal rhythm, in bioluminescent species (fireflies). 

In recent years Greenfield has mainly focused on comparative studies encompassing the role of rhythm and entrainment across arthropod and vertebrate species, including humans – where these abilities are at the heart of music, dance and related activities. He was an organizer of a  workshop on the topic, ‘Synchrony and rhythm interaction : from neurons to ecology’ held at the Lorentz Center, Leiden Univ., Netherlands, July 2019 and then an editor of a resulting theme issue in the Philosophical Transactions of the Royal Society B, ‘Synchrony and rhythm interaction: from the brain to behavioral ecology’ (2021).

Overall, Greenfield has published over 120 research articles and 16 chapters in edited books.  He has directed or co-directed 15 doctoral students and trained 10 post-doctoral scholars.   

Distinctions

Fellow, Smithsonian Institution (1978 - 1979) 

Fellow, Animal Behavior Society (2002 - )   

Fellows Lecture, Animal Behavior Society Congress (2004) 

Plenary Lecture, Communiction in Ecological Systems, Ben Gurion Univ., Sde Boqer, Israel (2008)                

Von Helversen Lecture, Invertebrate Sound and Vibration Congress (2013)