Earwigs Infected with Parasitic Worms Head Towards Water

Topic: Biology

Researchers at the University of Otago found that earwigs infected with a parasitic roundworm called Mermis nigrescens tend to head towards open water. They used RNA sequencing to study the genes of both the host and the parasite. The findings suggest that the infected insects' march toward water is accompanied by changes in gene activity.

Earwigs are small, elongated insects with distinctive pincers at the rear of their abdomens. While many earwig species are attracted to damp environments, they typically avoid open water. However, past studies have found that European earwigs infected with a parasitic roundworm called Mermis nigrescens tend to head towards open water.

Researchers at the University of Otago in New Zealand, the New Zealand Institute for Bioeconomy Science Limited, the University of British Columbia and Brown University recently sought to shed light on the genetic processes contributing to this unusual behavior. Their findings, presented in a paper published in Proceedings of the Royal Society B: Biological Sciences, suggest that the infected insects' march toward water is accompanied by changes in gene activity in both earwigs and the worms infecting them.

The researchers collected European earwigs and compared uninfected individuals with those at early and late stages of a Mermis nigrescens infection. They examined the insects using RNA sequencing, a technique that measures RNA molecules produced when genes are active. By comparing gene activity in both the parasite and its host at multiple stages of infection, they identified coordinated changes in thousands of genes.

The researchers detected activity from 12,876 earwig genes and 9,722 roundworm genes. Across comparisons of all sampled stages, they found that 673 earwig genes and 2,672 worm genes became more active, while the activity of 593 earwig genes and 2,293 worm genes dropped.

Why It Matters

This study can help us understand how parasites manipulate their hosts' behavior. It's a fascinating example of how complex interactions between species can lead to unusual behaviors.

Key Facts

• Earwigs infected with Mermis nigrescens tend to head towards open water, unlike uninfected earwigs.
• The researchers used RNA sequencing to study the genes of both the host and the parasite.
• The findings suggest that changes in gene activity contribute to the water-seeking behavior in infected earwigs.
• 12,876 earwig genes and 9,722 roundworm genes were detected as active during the infection process.
• 673 earwig genes and 2,672 worm genes became more active, while 593 earwig genes and 2,293 worm genes dropped in activity.

Key Terms

RNA sequencing

A technique that measures RNA molecules produced when genes are active.

Parasitic roundworm

A type of parasite that infects and manipulates the behavior of its host.

Implications

This study can help us understand how parasites manipulate their hosts' behavior. It's a fascinating example of how complex interactions between species can lead to unusual behaviors.