RSG: The evolution of vibrational communication in island endemics: function, fitness implications, ontogeny, and phylogeny of seismic signaling in the New Zealand Deinacrida

Augustana University Association, Sioux Falls SD

Investigators

Abstract

Understanding the functional mechanisms and evolutionary origins of animal communication through substrate borne vibration is an important problem in behavioral ecology. The availability of technologies such as portable laser Doppler vibrometers, highly sensitive piezoelectric films and transducers, and portable neurophysiology preparations allow investigators to address a broad array of questions associated with vibrational communication. This research tests hypotheses regarding the form, function, fitness implications, ontogeny, and phylogeny of vibrational communication among the extant New Zealand Deinacrida. This work addresses the following questions with respect to each of the eleven species of New Zealand giant weta: 1) Does the species produce vibrational signals for the purpose of intraspecific communication, and if so what are the spectral and temporal characteristics of the signals? 2) What is the neurophysiological range of response to seismic stimuli in the species? 3) Under what social contexts are the signals produced, and does signal character change with context? 4) What are the fitness related implications for vibrational signaling in the species (assessment benefits in inter male contests, female assessment of mate condition)? 5) How does the use of vibration change over the course of development in the species (predator avoidance to reproductive function)? 6) How do the form and function of vibrational signals compare between species? , and 7) Is there a relationship between vibrational signaling and ecological niche? In the last two decades there has been a growing interest in understanding the functional mechanisms and evolutionary origins of animal communication. New technologies such as portable laser Doppler vibrometers allow investigators to address a broad array of questions associated with vibrational communication in insects. This work will improve understanding of the selective pressures and evolutionary patterns that have resulted in the prevalence of vibrational signaling for communication. Using laser Doppler vibrometry in the field, extracellular electrophysiology in the laboratory, together with sound and high-speed video analysis of the New Zealand giant weta, key hypotheses in vibrative communication will be tested. Data collection and analysis will be performed by undergraduate research students from Augustana College and by students of Maori descent enrolled at Victoria University of Wellington.