02413nas a2200301   4500008004100000020001400041245012000055210006900175260000900244300001200253490000700265520138000272653002501652653003601677653002301713653003401736653002201770653001701792653002801809653001501837653001401852653007201866653001501938653003401953653005901987100002402046856004102070       2010                        eng d  a0269-846300aDifferential selection on sprint speed and ad libitum feeding behaviour in active vs. sit-and-wait foraging spiders0 aDifferential selection on sprint speed and ad libitum feeding be  c2010  a392-3990 v243 a1. Many animals are adapted for a 'feast or famine' existence, and will opportunistically engage in gluttonous foraging bouts. However, how gluttonous feeding influences individual performance (e.g. running speed) and the fitness consequence of modified performance are not frequently considered. 2. Using laboratory track trials I establish baseline locomotor performances (burst speed) for four spider species: two active foragers (Hogna helluo and Schizocosa ocreata (family: Lycosidae)), and two sit-and-wait foragers (Agelenopsis emertoni and Barronopsis texana (family: Agelenidae)). I then fed each species ad libitum, assessed what influence this meal had on individuals' burst speed relative to baseline performance, and performed a field census to assess selection on running speed for all four species. 3. Sit-and-wait foragers fed significantly more than active foragers and slowed significantly after feeding; however, neither active forager was slowed by their meal. 4. My field census detected no selection on speed for sit-and-wait foragers, and positive directional selection on speed for both active foragers. 5. The negative association between the amount of food consumed and selection on burst speed suggests that selection pressures to maintain locomotor performance may set an upper limit to how much an animal can, or will, eat during a foraging bout.10aAgelenopsis emertoni10aAgelenopsis emertoni (Araneae).10aBarronopsis texana10aBarronopsis texana (Araneae).10aFeeding behaviour10aHogna helluo10aHogna helluo (Araneae).10aLocomotion10aNutrition10aocreata [Feeding rate / Ad libitum feeding / ] [Foraging / Foraging10aSchizocosa10aSchizocosa ocreata (Araneae).10astrategies / ] [Running / Burst speed performance / ].1 aPruitt, Jonathan, N  u<Go to ISI>://ZOOREC:ZOOR14612083580