JOHN WILEY JONES DISTINGUISHED LECTURESHIP IN SCIENCE
HIDE AND SEEK IN THE OPEN SEA: USING COLOR, CLARITY, MIRRORS, AND LAMPS FOR CAMOUFLAGE
SPEAKER: Sönke Johnsen, Duke
LOCATION: A300 Thomas Gosnell Hall
Camouflage is exceptionally challenging in open ocean environments, due to their featureless nature. Thus, it is perhaps no surprise that the animals that live in this world have evolved highly sophisticated camouflage strategies, three of which – transparency, mirrors, and counter-illumination – are rare or absent in all other habitats.
The visual systems of the predators are equally complex, and several visual capabilities, including ultraviolet and polarization sensitivity and special filters filters, are thought to facilitate detection of camouflaged animals.
This talk reviews the optical nature of this enormous and mysterious realm and both the camouflage and camouflage-breaking strategies of its inhabitants, focusing primarily on underlying principles and what remains to be discovered.
A theme throughout is that far more is known about the optical and visual structures involved than about their function, and that this imbalance is primarily due to the rarity of observations of undisturbed behavior.
Originally trained in mathematics and art, Sönke Johnsen has studied camouflage, signaling, and non-human visual modalities for the last 27 years. He is particularly interested in vision and camouflage in the open ocean, but has also worked on coastal and terrestrial species, magnetoreception, nocturnal illumination, and human cataracts. His research combines mathematical analyses with behavioral and morphological studies and in situ measurements and observations. His field work primarily involves open-ocean research cruises that use SCUBA and deep-sea submersibles. In addition to exploring the evolution and diversity of the optical and visual tricks that animals perform, Professor Johnsen is interested in improving communication between theoretical and experimental scientists and between scientists and artists. Outreach is a strong focus and his research has been presented in numerous magazines, newspapers and television shows. Professor Johnsen has also written two books, The Optics of Life and Visual Ecology, and is currently working on a third for a lay audience. In his spare time, he is an avid nature photographer and amateur farmer.