How Do Spiders Reach Into Large Gaps?
WouterSpiders use silk to build webs and trap prey. The strength of their silk threads allows them to “tightrope walk” on top of things. This is how they reach into gaps and other places. Some spiders use drag lines to spin webs. They also produce a light, floaty silk that can stick to objects further away.
There are two major types of orb-webs. There are aerial orb-webs that capture mid-flight insects. There are also substrate-bound orb-webs that intercept ambulatory prey. The molecular structures of the orb-web silks are highly divergent.
Spiders use a combination of their silk biomechanical properties, web architecture, and genetics to capture and subdue their prey. They can adjust their silk properties by changing amino acid content or by changing the macrostructure of the silk. They are also able to change their fibre thickness.
The biomechanical properties of spiders’ silks are important for understanding the evolution of their webs. However, behavioural studies of spiders rarely consider these aspects.
A significant gap remains in our knowledge of the evolutionary forces that have driven the evolution of their webs. These forces include competition and adaptations to different kinds of environments. These interactions have significant ecological implications.
Several hypotheses are proposed to explain the repeated evolution of derived orbicularian families away from their ancestors’ typical planar orb-web. The competition may have been a key driver of this process. In addition, the adaptive capacity of individual silks to different types of environments may have shaped the overall design of the orb-web.
