Phenotype-environment matching in sand fleas.
Camouflage is perhaps the most widespread anti-predator strategy in nature, found in numerous animal groups. A long-standing prediction is that individuals should have camouflage tuned to the visual backgrounds where they live. However, while several studies have demonstrated phenotype-environment associations, few have directly shown that this confers an improvement in camouflage, particularly with respect to predator vision. Here, we show that an intertidal crustacean, the sand flea (Hippa testudinaria), has coloration tuned to the different substrates on which it occurs when viewed by potential avian predators. Individual sand fleas from a small, oceanic island (Ascension) matched the colour and luminance of their own beaches more closely than neighbouring beaches to a model of avian vision. Based on past work, this phenotype-environment matching is likely to be driven through ontogenetic changes rather than genetic adaptation. Our work provides some of the first direct evidence that animal coloration is tuned to provide camouflage to prospective predators against a range of visual backgrounds, in a population of animals occurring over a small geographical range.
Centre for Ecology & Conservation, College of Life & Environmental Sciences, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE, UK martin.stevens@exeter.ac.uk.
Martin
M
Stevens
Centre for Ecology & Conservation, College of Life & Environmental Sciences, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE, UK.
Annette C
AC
Broderick
Centre for Ecology & Conservation, College of Life & Environmental Sciences, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE, UK.
Brendan J
BJ
Godley
Centre for Ecology & Conservation, College of Life & Environmental Sciences, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE, UK.
Alice E
AE
Lown
Centre for Ecology & Conservation, College of Life & Environmental Sciences, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE, UK.
Jolyon
J
Troscianko
Centre for Ecology & Conservation, College of Life & Environmental Sciences, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE, UK Conservation Office, Ascension Island Government, Georgetown, Ascension Island, ASCN 1ZZ, South Atlantic Ocean.
Nicola
N
Weber
Centre for Ecology & Conservation, College of Life & Environmental Sciences, University of Exeter, Penryn Campus, Penryn, Cornwall TR10 9FE, UK Conservation Office, Ascension Island Government, Georgetown, Ascension Island, ASCN 1ZZ, South Atlantic Ocean sam.weber@ascension.gov.ac.
Sam B
SB
Weber
D000818:Animals; D001266:Atlantic Islands; D001717:Birds / Q000502:physiology; D003118:Color Perception; D033364:Decapoda / Q000502:physiology*; D017753:Ecosystem; D010641:Phenotype; D010858:Pigmentation; D011235:Predatory Behavior
camouflage; coloration; phenotype–environment; predation