Signals and signal choices made by the araneophagic jumping spider Portia fimbriata while hunting the orb-weaving web spiders Zygiella x-notata and Zosis geniculatus

Citation
M. Tarsitano et al., Signals and signal choices made by the araneophagic jumping spider Portia fimbriata while hunting the orb-weaving web spiders Zygiella x-notata and Zosis geniculatus, ETHOLOGY, 106(7), 2000, pp. 595-615
Citations number
36
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Animal Sciences","Neurosciences & Behavoir
Journal title
ETHOLOGY
ISSN journal
0179-1613 → ACNP
Volume
106
Issue
7
Year of publication
2000
Pages
595 - 615
Database
ISI
SICI code
0179-1613(200007)106:7<595:SASCMB>2.0.ZU;2-P
Abstract
Portia fimbriata is a web-invading araneophagic jumping spider (Salticidae) . The use of signal-generating behaviours is characteristic of how P. fimbr iata captures its prey, with three basic categories of signal-generating be haviours being prevalent when the prey spider is in an orb web. The predato ry behaviour of P. fimbriata has been referred to as aggressive mimicry, bu t no previous studies have provided details concerning the characteristics of P.fimbriata's signals. We attempt to determine the model signals for P. fimbriata's 'aggressive mimicry' signals. Using laser Doppler vibrometer an d the orb webs of Zygiella x-notata and Zosis geniculatus, P. fimbriata's s ignals are compared with signals from other sources. Each of P. fimbriata's three categories of behaviour makes a signal that resembles one of three s ignals from other sources: prey of the web spider (insects) ensnared in the capture zone of the web, prey making faint contact with the periphery of t he web and large-scale disturbance of the web (jarring the spider's cage). Experimental evidence from testing P. fimbriata with two sizes of lure made from Zosis (dead, mounted in a lifelike posture in standard-size orb web) clarifies P. fimbriata's signal-use strategy: (1) when the resident spider is small, begin by simulating signals from an insect ensnared in the captur e zone (attempt to lure in the resident spider); (2) when the resident spid er is large, start by simulating signals from an insect brushing against th e periphery of the web (keep the resident spider out in the web, but avoid provoking from it a full-scale predatory attack); (3) when walking in the r esident spider's web, regardless of the resident spider's size, step toward the spider while making a signal that simulates a large-scale disturbance of the web (mask footsteps with a self-made vibratory smokescreen).