Ahoy there! Scientists learn why spiders are able to ‘sail’ the seas

Scientists have figured out why spiders are able to walk on water. They’ve learnt arachnids are able to travel across water like ships, using their legs as sails and silk as an anchor. Spiders were already known to take to the air on “ballooning” flights, using their silk to catch the wind and carry them up to 30 kilometres a day but now they’ve spiders shown to be sailors as well as aviators.

We’ve now found that spiders actively adopt postures that allow them to use the wind direction to control their journey on water. They even drop silk and stop on the water surface when they want.

Dr Morito Hayashi, from the Natural History Museum in London

Tests carried out on trays of water showed that many species adopted elaborate postures, such as lifting a pair of legs, to take advantage of wind currents. In this way they “sailed” in turbulent, still, fresh and salt water conditions. Sailing spiders were also observed using their silk as “anchors” to slow themselves down or stop moving across water. The scientists found that spiders adopting “ballooning” behaviour for airborne dispersal were also the most eager and able “sailors”.

If landing on water poses no problem then in a week or two they could be a long way away from where they started.

Dr Sara Goodacre, from the University of Nottingham

Science