title: Are wet-induced wrinkled fingers primate rain treads?
abstract: Wet fingers and toes eventually wrinkle, and this is commonly attributed by lay opinion to local osmotic reactions. However, nearly a century ago surgeons observed that no wrinkling occurs if a nerve to the finger has been cut. Here we provide evidence that, rather than being an accidental side effect of wetness, wet-induced wrinkles have been selected to enhance grip in wet conditions. We show that their morphology has the signature properties of drainage networks, enabling efficient removal of water from the gripped surface.
authors.affiliation: 2AI Labs, Boise, Idaho, USA. changizi@2ai.org
authors.forename: Mark
authors.initials: M
authors.lastname: Changizi
authors.forename: Romann
authors.initials: R
authors.lastname: Weber
authors.forename: Ritesh
authors.initials: R
authors.lastname: Kotecha
authors.forename: Joseph
authors.initials: J
authors.lastname: Palazzo
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology; D000818:Animals; D005075:Biological Evolution; D005385:Fingers / Q000033:anatomy & histology* / Q000502:physiology*; D018737:Hand Strength / Q000502:physiology; D006801:Humans; D011323:Primates; D011891:Rain; D014867:Water
chemical_list: D014867:Water