Page 51 - BBC Wildlife Volume 36 #10
P. 51
WILDNEWS By J P
STUART BLACKMAN,
JAMES FAIR, HELEN
PILCHER, NIKI RUST,
SIMON BIRCH
and O RICE
KEEPING YOU UP TO DATE WITH HE BIG NATURE STORIES
T
Clownfish Amphiprion
ocellaris signal their host
anemone’s danger. Inset,
below: A. ephippium’s warning
coloration is not compromised
with camouflaging stripes.
EVOLUTION
Whatisitthatmakesclownssoscary?
Clownish colours warn of danger – but it’s not the ish that predators are meant to fear.
emo, the cartoon clownfish that lost who led the work. And now he has an clownfish species sporting more white
N its way, is not the most intimidating answer. Working with Jennifer Kelley of stripes, which Merilaita and Kelley
of characters. And yet new research has The University of Western Australia, he believe is more to do with camouflage
found clownfish colours evolved, in part, has found a correlation between the colour among the tentacles. But what of the
to instil fear into predators. But these are patterns of the fish and the potency of classic Nemo clownfish look, with
warning colours with a big difference. venom deployed by their hosts. The more both bright colours and white stripes?
Clownfish are famous for the intimate dangerous the anemone, the brighter Merilaita says it may be a compromise
relationships they form with sea anemones. the clownfish’s colours. The fish are between camouflage and threat.
Top: Reinhard Dirscherl/FLPA; bottom: Georgette Douwma/naturepl.com
They seek protection among anemone palatable: it’s the host anemone that the “The balance is between avoidance of
tentacles, apparently immune to stings, fish are warning predators about. “We detection by predators at long range and
and in return they aerate their hosts do not know of any other warning of the toxicity of the host at a
and fertilise them with nutrients. The animal groups that closer range.” Nemo, it seems, would
30-odd clownfish species specialise in might advertise a rather not be found. But should he
partnering different species of anemone defence possessed be spotted, his message is clear:
and come in a wide range of bright by another “Get lost!” SB
colours and white stripes. species,” write
“I’ve had the question about the the biologists. FIND OUT MORE
function of their peculiar coloration in Less venomous Journal of Evolutionary Biology:
my head for a long while,” says Sami anemones host https://onlinelibrary.wiley.com/
Merilaita of Finland’s University of Turku, less colourful doi/abs/10.1111/jeb.13350
October 2018 BBC Wildlife 51
