Adaptable night camouflage by cuttlefish.
Cephalopods are well known for their diverse, quick-changing camouflage in a wide range of shallow habitats worldwide. However, there is no documentation that cephalopods use their diverse camouflage repertoire at night. We used a remotely operated vehicle equipped with a video camera and a red light to conduct 16 transects on the communal spawning grounds of the giant Australian cuttlefish Sepia apama situated on a temperate rock reef in southern Australia. Cuttlefish ceased sexual signaling and reproductive behavior at dusk and then settled to the bottom and quickly adapted their body patterns to produce camouflage that was tailored to different backgrounds. During the day, only 3% of cuttlefish were camouflaged on the spawning ground, but at night 86% (71 of 83 cuttlefish) were camouflaged in variations of three body pattern types: uniform (n=5), mottled (n=33), or disruptive (n=34) coloration. The implication is that nocturnal visual predators provide the selective pressure for rapid, changeable camouflage patterning tuned to different visual backgrounds at night.
Hanlon
Roger T
RT
Marine Resources Center, Marine Biological Laboratory, Woods Hole, Massachusetts 02543, USA. rhanlon@mbl.edu
Naud
Marie-José
MJ
Forsythe
John W
JW
Hall
Karina
K
Watson
Anya C
AC
McKechnie
Joy
J
D000220:Adaptation, Biological / Q000502:physiology*; D000818:Animals; D003624:Darkness; D010858:Pigmentation / Q000502:physiology*; D012641:Selection, Genetic; D049833:Sepia / Q000502:physiology*; D013021:South Australia; D014741:Video Recording