TY - JOUR
T1 - Through predators' eyes
T2 - phenotype-environment associations in shore crab coloration at different spatial scales
AU - Nokelainen, Ossi
AU - Hubbard, Nik
AU - Lown, Alice E.
AU - Wood, Louisa E.
AU - Stevens, Martin
PY - 2017/12/1
Y1 - 2017/12/1
N2 - Phenotype-environment associations in coloration often involve camouflage, enabling organisms to blend into their environment and thereby reducing predatory attacks. The nature of any associations may vary among receivers with different visual systems and at different spatial scales, but these effects have rarely been investigated together. We studied shore crabs (Carcinus maenas), at seven intertidal sites in the south-west UK. We used image analysis and vision modelling to examine the relationships with predator vision (bird/fish), crab maturity (adult/juvenile) and habitat spatial scale (meso/micro) on shore crab coloration, in order to establish links between crab appearance and habitat. We show that crabs are likely to be more colourful to tetrachromatic birds than to dichromatic fish, while fish may see the crabs as being lighter and with larger patterns. Adult crabs had more uniform coloration, whereas juveniles showed more variable colour patterns. At the mesoscale, rock pool and mussel habitats harboured crabs with more variable coloration, whereas crabs from mudflats were more uniform. Comparisons at the microscale revealed a wide range of carapace variation, including divergent crab patterning on red and green algal beds. Our findings have implications for the evolution of camouflage under multi-species predation risk in heterogeneous environments in nature.
AB - Phenotype-environment associations in coloration often involve camouflage, enabling organisms to blend into their environment and thereby reducing predatory attacks. The nature of any associations may vary among receivers with different visual systems and at different spatial scales, but these effects have rarely been investigated together. We studied shore crabs (Carcinus maenas), at seven intertidal sites in the south-west UK. We used image analysis and vision modelling to examine the relationships with predator vision (bird/fish), crab maturity (adult/juvenile) and habitat spatial scale (meso/micro) on shore crab coloration, in order to establish links between crab appearance and habitat. We show that crabs are likely to be more colourful to tetrachromatic birds than to dichromatic fish, while fish may see the crabs as being lighter and with larger patterns. Adult crabs had more uniform coloration, whereas juveniles showed more variable colour patterns. At the mesoscale, rock pool and mussel habitats harboured crabs with more variable coloration, whereas crabs from mudflats were more uniform. Comparisons at the microscale revealed a wide range of carapace variation, including divergent crab patterning on red and green algal beds. Our findings have implications for the evolution of camouflage under multi-species predation risk in heterogeneous environments in nature.
KW - avian vision
KW - camouflage
KW - Carcinus maenas
KW - fish vision
KW - predator-prey interactions
KW - vision modelling
KW - UKRI
KW - BBSRC
KW - BB/G022887/1
UR - http://www.scopus.com/inward/record.url?scp=85048702967&partnerID=8YFLogxK
UR - https://ore.exeter.ac.uk/repository/handle/10871/28718?show=full
U2 - 10.1093/BIOLINNEAN/BLX101
DO - 10.1093/BIOLINNEAN/BLX101
M3 - Article
AN - SCOPUS:85048702967
SN - 0024-4066
VL - 122
SP - 738
EP - 751
JO - Biological Journal of the Linnean Society
JF - Biological Journal of the Linnean Society
IS - 4
ER -