Squash Bugs Nymph Seek Out Adults’ Poop Looking for Essential Microbe Needed for Its Survival

Almost all animals share basic requirements for survival such as food, shelter, and safety. Although some animals differ in the way they were delivered at birth, most babies rely on at least one of their parents to provide for their needs and for protection. In the family of insects, one species stands out in terms of the basic need sought by its newborn.

(Photo : Wikimedia Commons/ Katja Schulz)

Specialized Acquisition Behaviors

Squash bugs (Anasa tristis) are known for being highly attracted to microbe-rich feces. This is because they need to acquire a species of bacteria called Caballeronia in the first three weeks of their lives. The baby squash bugs that do not find microbes die. Unfortunately, Caballeronia is not abundant in the environment and fending for themselves is a risky technique on the part of the nymphs.

There are other insects that do this technique. Upon laying their eggs, the mother insect defecates on them, leaving behind the essential microbes that the baby insects can slurp up. Until today, it is still unclear how the young squash bugs acquire Caballeronia upon birth.

Evolutionary biologist and behavioral ecologist Scott Villa of Davidson College in North Carolina discovered the answer to this mystery when they caught an adult squash bug defecating on camera while working on different research. They observed that nymphs gathered to the adult feces and started feeding. They witnessed that the baby bugs immediately got attracted to the feces.

The research team conducted a series of behavioral and transmission experiments which focus on tracking at strain level. The experiment demonstrates that the young squash bugs can successfully find feces in the presence and absence of the adult bugs. To pick up the bacteria, the fledging squash bugs use the flush feeding strategy to acquire the bacteria from fecal matter.

The result of the study also suggest that fecal attraction could also be specific to certain species. It was revealed that the nymphs are not so successful at picking up Caballeronia from adult poop belonging to Anasa andresii, their close squash bug relative.

Experts are still mystified why Caballeronia is important for squash bugs, but they believe that these bacteria could probably play a significant role in ensuring that the insects obtain the nutrients they need from the food that they eat.

The study provides a new insight into the behavior of squash bugs which are known for being agricultural pests. Figuring out how the baby bugs obtain their major survival requirement can help the experts interrupt the bacterial supply chain and control the population of the insect.

Destructive Nature of Squash Bugs

Squash bugs are one of the major pests in vegetable gardens. They like to thrive in squash, pumpkin, and zucchini because these plants are large and can provide them with food, shelter, and egg-laying spots. When present in high number, the squash bugs can injure both the leaf and the fruit.

Young seedlings and plants in their flowering stage are the most vulnerable target of squash bug feeding. Their young and adult members feed on plant juices and release toxic substances into the leaves. As they suck the sap with their piercing-sucking mouthparts, they leave the plants wilted and dry.