Research in the Lohmann Lab
Orientation and navigation behavior of sea turtles
One project involves research on how young loggerhead sea turtles guide themselves during their 9,000 mile (15,000 kilometer) migration across the Atlantic Ocean and back. This project is described in detail on our sea turtle navigation web page.
Magnetic orientation in spiny
lobsters
The western Atlantic spiny lobster Panulirus argus undergoes an
annual
migration and is also capable of homing to specific dens in its coral
reef environment. Experiments carried out in the Florida Keys have demonstrated that
lobsters can detect the earth's magnetic field and derive directional
information from it. Present research is directed at determining: (1)
how lobsters use information from the earth's field to guide their
movements; (2) how geomagnetic cues are transduced to the nervous
system.
Neurobiological mechanism of magnetic field
detection in molluscs
Another project involves electrophysiological research on the nudibranch
mollusc (sea slug)Tritonia. Behavioral experiments have
demonstrated that Tritonia can orient using the earth's magnetic
field, but the physiological mechanisms that underlie magnetic field detection have not been clearly established. Using
intracellular recording procedures, we have identified four neurons in the brain of Tritonia that respond with enhanced electrical activity to changes in earth-strength fields. We are very excited about this work because these cells are
the only identifiable neurons known to be responsive to
geomagnetic field stimuli in any animal. Thus, whereas most previous research on magnetic
field detection has relied on indirect behavioral approaches to infer
properties of magnetoreceptors, the Tritonia system provides an
opportunity to study directly how the brain of a simple animal detects magnetic fields.
Click here to view a poster on
Tritonia research that was presented by Shaun
Cain at a recent symposium.