Scientists have uncovered the mechanism by which the spider web adapts to different humidity conditions. article about it published Frontiers in Ecology and Evolution.
The ability to spin silk and create insect traps is essential to the survival of many spider species. At the same time, the web must be both cohesive and strong to successfully retain victims. The mesh is made sticky with water-soluble protein glue. Circular weavers with a roughly similar genotype live in a variety of climatic zones, while glue absorbs water from the atmosphere and must be optimized for specific humidity conditions. In this context, scientists are interested in how spiders adapt to climate.
Nadia Ayoub of the University of Washington and her colleagues decided to study orb weavers. argiope argentataliving in dry environments Argiope trifasciataliving in humid environments. Spider web A. trifasciata collected in nature and argentata forced to spin in the lab while feeding on food they usually consume freely.
As a result, it turned out that there are drops of spider glue. argentata less A. trifasciata absorbs less water as humidity increases. They also had smaller protein particles occupying a smaller portion of the droplet volume. For both spider species, the strength of the adhesive droplets depends on the hardness of the protein particles and argentata decreased as humidity increased. Glue drops for threads argentataas a rule, they were located closer together and more cohesive.
The scientists also analyzed the proteins found in the glue droplets to understand how these differences in material properties arise. Although the proteins they found were similar, they appeared in different proportions, and the adhesive argentata contained protein products of four genes not present in the adhesive A. trifasciata. These additional proteins and the more balanced ratio of AgSp1 and AgSp2 proteins may explain both the higher strength of this adhesive and its lower water absorption capacity.
Previously, biologists confirmed that moths have “tails.” work as bait for bats.