Some spiders begin to lose their sight when they are hungry

Biologists at the University of Cincinnati have discovered a surprising feature in jumping spiders (Salticidae). They noticed that when its representative is hungry, it begins to lose light-sensitive cells – crucial for the sense of sight.

Spiders of this family are very specific. They usually do not weave webs, but hunt their victims by jumping in. That’s why their sense of sight is so important.

The observations were made by Professor Elke Buschbeck and colleagues. She studied photoreceptors in the eyes of spiders from this family. It turned out that when these animals are hungry, they lose very important receptors. Details of the research on this topic have been published in the journal Vision Research.

Researchers caught wild spiders in their natural habitat and then examined their eyes using special equipment. In some cases, they found dark spots on the photoreceptors. They said they may have degraded during life or development.

“You could say that some of the photoreceptors died,” Buschbeck said. However, scientists began to wonder what could have caused this.

To test this, the scientists divided the spiders into two groups. One of them was fed normally, the other got half the amount of food. The group that received less food lost many more photoreceptors, especially in the retina.

“It’s the functional equivalent of the macula in our eyes,” Buschbeck said. – Photoreceptors are expensive in terms of energy requirements. It’s hard to keep up with their energy needs. If you deprive them of their nutrition, the system starts to fail, she added.

According to the researchers, jumping spiders can be a very good model for studying the health of the retina and neurons.

Macular degeneration – one of the most serious eye diseases – affects about 20 million Americans. It is the most common cause of vision loss and unfortunately there is no cure for it. “Interestingly, there is evidence that macular degeneration in humans is linked to metabolic processes and energy supply difficulties,” said Buschbeck.

However, it is too early to draw firm conclusions about the similarities between eye diseases in spiders and humans, said senior author Annette Stowasser of the study.

‘To be able to say anything about how our analyzes might affect human treatment, other carefully designed studies would first need to establish exactly which nutrients are important, and to what extent this may depend on environmental conditions or other factors,’ she said. “However, the fact that nutrient deprivation can have such consequences underscores how important they are,” she added.

– Wouldn’t it be crazy if a breakthrough in the treatment of macular degeneration in humans was inspired by work on jumping spiders, which are common in backyards throughout the United States? Sometimes answers to difficult questions can come from unexpected places, concluded Professor Nathan Morehouse, who was also involved in the research.