Saccadic tracking of targets mediated by the anterior-lateral eyes of jumping spiders
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The modular visual system of jumping spiders (Salticidae) divides characteristics such as high spatial acuity and wide-field motion detection between different pairs of eyes. A large pair of telescope-like anterior-median (AM) eyes is supported by 2–3 pairs of ‘secondary’ eyes, which provide almost 360 degrees of visual coverage at lower resolution. The AM retinae are moveable and can be pointed at stimuli within their range of motion, but salticids have to turn to bring targets into this frontal zone in the first place. We describe how the front-facing pair of secondary eyes (anterior lateral, AL) mediates this through a series of whole-body ‘tracking saccades’ in response to computer-generated stimuli. We investigated the ‘response area’ of the AL eyes and show a clear correspondence between the physical margins of the retina and stimulus position at the onset of the first saccade. Saccade frequency is maximal at the margin of AL and AM fields of view. Furthermore, spiders markedly increase the velocity with which higher magnitude tracking saccades are carried out. This has the effect that the time during which vision is impaired due to motion blur is kept at an almost constant low level, even during saccades of large magnitude.
KeywordsVision Salticidae Motion detection Spider Saccade
We thank María Castillo-Pando (animal care), Rowan McGinley (spider collection), Ben Fanson and Eirik Søvik (helpful discussions). This work was supported by an Australian Research Council Discovery Grant (DP0772517) to XJN and by a Macquarie University Research Excellence Scholarship (DBZ).
- Harland D, Jackson RR (2000) “Eight-legged cats” and how they see–a review of recent research on jumping spiders (Araneae: Salticidae). Cimbebasia 16:231–240Google Scholar
- Harland D, Jackson RR (2004) Portia Perceptions: the Umwelt of an araneophagic jumping spider. In: Prete FR (ed) Complex worlds from simpler nervous systems. MIT Press, Cambridge, pp 5–40Google Scholar
- Harland D, Li D, Jackson RR (2012) How jumping spiders see the world. In: Lazareva OF, Shimizu T, Wasserman EA (eds) How animals see the world: comparative behavior, biology, and evolution of vision. Oxford University Press, New York, pp 133–164Google Scholar
- Homann H (1928) Beiträge zur Physiologie der Spinnenaugen. J Comp Physiol A 7:201–268Google Scholar
- Land MF (1985) Fields of view of the eyes of primitive jumping spiders. J Exp Biol 119:381–384Google Scholar
- Mittelstaedt H (1957) Prey capture in mantids. In: Scheer BT (ed) Recent advances in invertebrate physiology. University of Oregon Press, Eugene, pp 51–71Google Scholar
- Nelson XJ, Jackson RR (2011a) Anti-Predator Behaviour. In: Herberstein ME (ed) Spider behaviour. Cambridge University Press, Cambridge, pp 51–73Google Scholar
- Nelson XJ, Jackson RR (2011b) Foraging Behaviour. In: Herberstein ME (ed) Spider behaviour. Cambridge University Press, Cambridge, pp 5–30Google Scholar
- O’Carroll DC (1989) An optical assessment of visual performance in the eyes of hunting spiders (Araneae:Labidognatha) Dissertation, The Flinders University of South AustraliaGoogle Scholar