"Beetles Utilize Their Butts to Absorb Water"

Scientists are beginning to understand how some beetles are able to "drink" using their butts. Red flour beetles, which are a major agricultural pest, have been observed opening their anus in order to allow water vapor in the air to flow into the lower gut and condense on any poop that may be there. The insects then draw water out of the fecal material using special cells that line their lower digestive system. Researchers believe that this unique mechanism could be used in the future to develop beetle-specific pesticides that will protect crops without harming beneficial insects like bees. Insect pests are responsible for destroying up to 20% of the global food supply every year and farmers worldwide are losing money as a result. Beetles are particularly resilient and can thrive even in arid environments with bone-dry crops. One adaptation that helps them survive is the ability to recycle water out of their poop using the rectal complex, but until now, scientists weren't sure how they managed to do it.

A study published on March 21 in Proceedings of the National Academy of Sciences found that in red flour beetles (Tribolium castaneum), the gene Nha1 is particularly active in cells that cover the lining of the rectal complex. Previous research had suggested that cells in the rectal complex were involved in absorbing water from material within the organ, but they did not appear to be particularly effective at transporting water. The new study suggests that Nha1 produces a protein that pumps charged potassium particles across cells' membranes, which leads to a concentration of ions on the outside of the rectal complex that could be used to transport water through the wall of the rectal complex and into the rest of the body through osmosis. Researchers confirmed that the beetles opened their anuses in high humidity to allow water vapor into the rectal complex. Beetles with Nha1 deactivated did not survive as well in dry conditions as normal beetles.

It is uncertain whether other species of beetles utilize a similar mechanism, but the study highlights the ability of nature to develop unique solutions to complex problems. As a nonprofit news organization, it's our mission to provide accurate, engaging science news to the public, and we rely on support from individuals like you to keep our content free and accessible to future scientists and engineers. Invest in quality science journalism by donating today.