Evolution of water surface locomotion by spiders: a comparative approach

摘要: Spiders vary enormously in their behaviour when placed on the surface of fresh water. In some families (e.g. Theridiidae), spider typically becomes wet and either sinks or is incapacitated by adhesion to other Agelenidae), remains dry moves across water using its legs much same way it does land, with members each leg pair moving alternation other. at least one family (Pisauridae), a rowing galloping gait which propulsive move synchrony While degree hydrophobicity widespread among spiders, ability occurs rarely; common only Lycosoidea, subset GST (Grate-Shaped Tapetum) clade. Our mapping locomotion representatives 42 spiders onto cladograms Araneae suggests that row evolved base clade includes Trechaleidae, Pisauridae Lycosidae independently Ctenidae. Rowing seen all subfamilies but, unlike animals tested showed behaviour, many individuals could did not do so time. Among 166 non-lycosoid species we have tested, found Araneidae two Salticidae can row. It evident from our data that, most phylogeny trumps recent selection (based habitat preference) determining spiders’ locomotor surface. © 2004 The Linnean Society London, Biological Journal Society, 2004, 81, 63–78.