Darwin Evolving: Distinguished NaturalistsDarwin Evolving: Distinguished Naturalists

Dr. Peter Narins with a frogNovember 2, 2010

Peter M. Narins
Departments of Integrative Biology & Physiology,
and Ecology & Evolutionary Biology,
UCLA

Darwin Evolving: Environmental influences on the evolution of communication systems

Abstract

Many species of animals, including man, face the formidable task of communicating in naturally noisy environments. From his travels in South America, Darwin was acutely aware of the musical quality of frog vocalizations, as well as their importance in communication in naturally noisy environments. In this talk, I shall review the evidence for the remarkable ability of amphibians to shift their call timing in response to both high-level interfering tones or to small intensity shifts in the background noise. We have explored communication behavior in a wide variety of taxa that appears to have evolved specifically to tailor and sculpt intraspecific communication systems. Finally, I shall present behavioral evidence that broadband environmental noise may act as a strong selective force in sculpting the acoustic communication systems of two species of two Old World arboreal frogs. The dramatic frequency shift into the ultrasonic range of the harmonic content of the advertisement calls likely represents an adaptation that prevents signals from being completely masked by the intense broadband background noise from local streams. Supported by NIH Grant no. DC-00222.

Bio

Dr. Narins has been carrying out pioneering work for more than 30 years on the selective pressures sculpting and mechanisms underlying the evolution of sound and vibration communication in amphibians and mammals. He grounds his research in a unique combination of rigorous experimental field studies and quantitative physiological measurements. He provided the first example, in the Puerto Rican coqui treefrog, of sexual dimorphism in a vertebrate sensory system. He discovered the mechanism that prevents the sensitive inner ear of this frog from being overstimulated when the male produces its extremely high intensity calls. More recently, his comparative research approach led to the discoveries of ultrasonic communication in the concave-eared torrent frog (China), the first species of songbird demonstrated to produce ultrasound (China), the first amphibian capable of modulating his call to produce purely ultrasonic calls (Malaysia), and a novel system of seismic communication in a remarkable sand-dwelling mammal, the Namib Desert golden mole (Namibia).

He has led or participated in 50 scientific overseas research expeditions to six continents plus Madagascar, and is in great demand as a plenary lecturer on the evolution of communication systems both in English worldwide and in Spanish to universities throughout Latin America and Spain.

He is an editor of the Journal of Comparative Physiology, and has served as Treasurer of the International Society of Neuroethology. He has received the Senior U.S. Scientist Award of the Alexander von Humboldt Foundation and a Fulbright Award (Montevideo, Uruguay). He was elected Fellow of the Guggenheim Foundation, Acoustical Society of America, Animal Behavioral Society, and AAAS. He is an Honorary Member of the Cuban Zoological Society and Professor Ad Honorem at the University of the Republic, Montevideo, Uruguay.