A study by biologists from James Cook University showed that the venom of some spiders varies according to external conditions and moods. The results of the study were published in the journal. magazine PLOS ONE.
“For the first time, it became clear how certain components of the venom might be related to certain behavioral and physiological characteristics of spiders. These links are context dependent. Roughly speaking, spiders change the toxicity of their venom according to their mood,” the scientists say.
The study’s authors examined the properties of toxins from four species of the Australian funnel-web spider Hadronyche valida, Hadronyche infensa, Hadronyche cerberea and Atrax robustus. They are the most poisonous in the world.
In total, the authors conducted three experiments. In the first, they imitated predatory behavior: by blowing air or poking spiders with tweezers. In the second, the spiders were placed in the same aquarium with their other relatives, and in the third, they were given the opportunity to explore new territories. In all three experiments, the researchers monitored the spider’s heart rate to measure metabolism.
After each experiment, the researchers took samples of the venom and analyzed their toxicity using mass spectrometry. The properties of the venom of each spider changed its indicators depending on the state of the arthropod: in Hadronyche valida, Hadronyche infensa and Hadronyche cerberea, the properties of the venom did not depend on external conditions, and in Atrax robustus, the toxicity of the venom was dependent on heart rate and protection from external threats.
Understanding how spiders produce venom and regulate their toxicity could be of use in medicine, the scientists say.