Professor Peter Teglberg Madsen

TY - JOUR

T1 - Detecting spring after a long winter

T2 - coma or slow vigilance in cold, hypoxic turtles?

AU - Madsen, Jesper G.

AU - Wang, Tobias

AU - Beedholm, Kristian

AU - Madsen, Peter T.

PY - 2013/12/23

Y1 - 2013/12/23

N2 - Many freshwater turtle species can spend the winter submerged in ice-covered lakes by lowering their metabolism, and it has been proposed that such severe metabolic depression render these turtles comatose. This raises the question of how they can detect the arrival of spring and respond in a sensible way to sensory information during hibernation. Using evoked potentials from cold or hypoxic turtles exposed to vibration and light, we show that hibernating turtles maintain neural responsiveness to light stimuli during prolonged hypoxia. Furthermore, turtles held under hibernation conditions for 14 days increase their activity when exposed to light or elevated temperatures, but not to vibration or increased oxygen. It is concluded that hibernating turtles are not comatose, but remain vigilant during over-wintering in cold hypoxia, allowing them to respond to the coming of spring and to adjust their behaviour to specific sensory inputs.

AB - Many freshwater turtle species can spend the winter submerged in ice-covered lakes by lowering their metabolism, and it has been proposed that such severe metabolic depression render these turtles comatose. This raises the question of how they can detect the arrival of spring and respond in a sensible way to sensory information during hibernation. Using evoked potentials from cold or hypoxic turtles exposed to vibration and light, we show that hibernating turtles maintain neural responsiveness to light stimuli during prolonged hypoxia. Furthermore, turtles held under hibernation conditions for 14 days increase their activity when exposed to light or elevated temperatures, but not to vibration or increased oxygen. It is concluded that hibernating turtles are not comatose, but remain vigilant during over-wintering in cold hypoxia, allowing them to respond to the coming of spring and to adjust their behaviour to specific sensory inputs.

KW - freshwater turtles

KW - responsiveness

KW - coma

KW - evoked potential

KW - hibernation

KW - hypoxia

KW - ANOXIA-TOLERANT VERTEBRATES

KW - FRESH-WATER TURTLE

KW - BRAIN

KW - STRATEGIES

KW - RESPONSES

KW - OXYGEN

U2 - 10.1098/rsbl.2013.0602

DO - 10.1098/rsbl.2013.0602

M3 - Journal article

C2 - 24108677

VL - 9

JO - Biology Letters

JF - Biology Letters

SN - 1744-9561

IS - 6

M1 - 20130602

ER -