French researchers have discovered a surprising ability of spiders to camouflage themselves simultaneously from their predators and prey, from their predators to avoid being eaten and from their prey to ambush them more easily. Despite the fact that their predators and prey have different vision systems and do not see in the same way.
Australian crab spider
Crab spider in Spain
Summary: The red spider mite is a spider that attacks bees. A spider that knows very well how to camouflage itself from bees. Also, in our shop in Las Rozas de Madrid you have at your disposal a fantastic selection of quality honeys. Honeys such as: orange blossom, eucalyptus, rosemary, thyme….
Researchers Marc Thëry and Jérôme Casas published their experiment with the crab spider. A spider capable of camouflaging itself in flowers with both pink and yellow petals, in the seminal journal Nature.
According to these researchers: Crab spiders (Thomisus onustus) hide in the flowers to hunt. Also, theyd camouflage themselves by taking on the same color as the flowers, in order to deceive both predators and their insect prey, including bees.
Although this strategy of mimicry is obvious to the human eye, it has never been studied with respect to different visualization systems. Well, birds are able to detect more colors than bees and the fields of vision of bees and birds have different sensitivities, making color matching more difficult.
Théry and Casas developed a new experiment to investigate how spiders manage so well with different fields of prey and predator visualization. To this end, the two researchers used a method called spectrometry to measure the reflected light from spiders in different flowers. They then reconstructed the two visualization systems, the bee system and the bird system.
They measured the color of the spider against different parts of the flowers, showing that the spiders were able to combine the colors of their bodies with those of their environment. From the point of view of birds and bees, there was no color contrast and the spider was essentially invisible.
However, birds and bees also use black and white vision to detect the brightness of moving objects in some cases. When the researchers tested the hiding under this vision system, they found that spiders could be seen by both prey and predators.
a) Previous research
Previous research has shown that other crab spider species are able to combine both colors and contrast brightness by camouflaging themselves from the vision of bees. It follows from this research that these spider mimicry systems may vary in each spider species.
Dr. Jochen Zeil of the Visual Science Group at the Australian National University of Biological Sciences Research School said this research creates many new questions.
How do spiders choose their surroundings to position themselves?. How do spiders combine color?. Finally, do some spiders combine color but not brightness, and others can combine both color and brightness?
Could this be a reflection of the limits that spiders can have? Or the pressure that spiders are under? Maybe different predators have different strategies, for example.
Vídeo 1: The crab spider
2. Crab spider is Spain
In Spain it can be found all over the Iberian Peninsula, but it is active during the spring months. It is active during these months due to the large number of flowers and therefore of insects that go to them. As it mimics the flowers very well, it is difficult to find, but in Spain they are very abundant.