Spiders in space—orb-web-related behaviour in zero gravity
Open Access
- 3 December 2020
- journal article
- research article
- Published by Springer Science and Business Media LLC in The Science of Nature
- Vol. 108 (1), 1-10
- https://doi.org/10.1007/s00114-020-01708-8
Abstract
Gravity is very important for many organisms, including web-building spiders. Probably the best approach to study the relevance of gravity on organisms is to bring them to the International Space Station. Here, we describe the results of such an experiment where two juvenile Trichonephila clavipes (L.) (Araneae, Nephilidae) spiders were observed over a 2-month period in zero gravity and two control spiders under otherwise identical conditions on Earth. During that time, the spiders and their webs were photographed every 5 min. Under natural conditions, Trichonephila spiders build asymmetric webs with the hub near the upper edge of the web, and they always orient themselves downwards when sitting on the hub whilst waiting for prey. As these asymmetries are considered to be linked to gravity, we expected the spiders experiencing no gravity to build symmetric webs and to show a random orientation when sitting on the hub. We found that most, but not all, webs built in zero gravity were indeed quite symmetric. Closer analysis revealed that webs built when the lights were on were more asymmetric (with the hub near the lights) than webs built when the lights were off. In addition, spiders showed a random orientation when the lights were off but faced away from the lights when they were on. We conclude that in the absence of gravity, the direction of light can serve as an orientation guide for spiders during web building and when waiting for prey on the hub.Keywords
Funding Information
- National Aeronautics and Space Administration (#NNJ10GA25A)
This publication has 36 references indexed in Scilit:
- An analysis of the orientation of an orb-web spiderJournal of Theoretical Biology, 2010
- Upside-down spiders build upside-down orb webs: web asymmetry, spider orientation and running speed in CyclosaProceedings. Biological sciences, 2010
- Ontogenetic Changes in Web Design in Two Orb‐Web SpidersEthology, 2010
- Nutrient balance affects foraging behaviour of a trap-building predatorBiology Letters, 2009
- Gravitropism in Higher Plants1Plant Physiology, 1999
- Comparison in the web structure between Nephila clavata L. KOCH and Nephila maculata (FABRICIUS) (Araneae: Araneidae), and the origin of genus NephilaActa Arachnologica, 1985
- Orientation in a vertical plane: The use of light cues by an orb-weaving spider, Araneus diadematus clerkAnimal Behaviour, 1984
- A functional explanation of top-bottom asymmetry in vertical orbwebsAnimal Behaviour, 1983
- Spider-Web BuildingScience, 1965
- Beiträge zur Kenntnis des Netzbaus orbiteler SpinnenZeitschrift Fur Tierpsychologie, 1951