What do locusts eat? Turns out, it’s so much more than just a herb

Figuring out what an animal is eating can be challenging, as this usually requires a detailed overview of the contents of their stomachs or time-consuming observations of how they feed in the wild. But there is a better way. The researchers carefully mapped the grasshopper’s lower jaw using 3D imaging techniques, revealing their eating habits.

Image credit: Wikipedia Commons.

Grasshoppers are insects of the suborder kylifera in the order orthoptraAlong with locusts and cockroaches. There are about 11,000 known species of grasshoppers and most of them are herbivores, feeding on different types of plants, especially grass. However, there are a few exceptions. Some grasshoppers are even carnivores and play an important role in grasslands and other ecosystems.

The parts of a locust’s mouth vary, depending on what they eat. Some have sharper cutting edges, while others have tougher eating-like edges. So far, researchers have only been able to assign grasshoppers to broad feeding categories. But now, a new study suggests a new way of looking at the diets of species scientists have limited information.

“Knowing what animals eat is key to understanding ecosystems, but working on that can be difficult and time-consuming, especially if the animals you’re studying are rare, small, or fast-moving,” said Chris Stocky, study co-author on the study. “One advantage of our method is the robust comparisons it provides.”

Grasshoppers and mammals

Dental topographic analysis (the detailed study of the shape of teeth) is used mostly for mammalian teeth – this is the first time it has been performed on other animals. For researchers, this method is not very demanding and provides a lot of good information as it can be used on any type of tooth-like structure.

Illustration of the lower jaw of a grasshopper with different landscapes adapted to different diets captured by dental topographic scales. The most intricate undulating landscapes are associated with tough vegetation such as weeds. Grasshoppers with steep terrain and steep cliff edges eat animals. Grasshoppers, along with other diets, have different combinations of these characteristics. Credit: Chris Stocky/University of Leicester.

Comparing the lower jaw of grasshoppers with the teeth of mammals allowed us to predict the grasshopper’s diet with an accuracy level of 82%, which is quite surprising, especially considering that the mouth parts of mammals and grasshoppers have evolved independently for more than 400 million years, according to Mark Burnell, co-author of the study. The author, said in a statement.

The researchers measured and analyzed the shapes of the grasshopper’s mouth parts as they would be the topography of the landscape, and found differences associated with diet. Purnell said that the lower jaws of those who eat plant matter have “a complex undulating landscape”, while the lower jaws of carnivorous grasshoppers have “more steep slopes and steeper cliff edges.”

In their study, the researchers used samples from museums. Since they have not seen these organisms alive, the only way to know their diets is to dissect them – a slow process that can also damage the samples and limit their use to further studies. That’s why this new method can be a way to learn from animals without causing any harm to them.

“This study is a great example of combining modern analytical methods with historical samples from museum collections to help understand the biodiversity of our planet. As technology advances, additional uses for museum collections are possible, and this non-destructive approach can reveal diet information for thousands of species,” he concluded. Ben Price, curator of the Nural History Museum, who was not involved in the study.

The study was published in the journal Methods in Ecology and Evolution.

Leave a Reply

%d bloggers like this: