Finding Something New

Cabras takes great care when she thinks she’s found something new. She immediately signals to any teammates around her to stop moving. “I get everybody to freeze!” she says. She doesn’t want any sudden movements to scare off a beetle. Before moving any closer, she tries to take a photograph of the scene. “I usually take photos of their food plant and habitat, because it gives new informationnot just to the taxonomists but also to the ecologists and conservationists.”

When the beetles feel vibrations on tree leaves, they fall to the ground. They are very hard to find in dead leaves.

teammates working in a forest

Many of the more than 400 species of Philippine jewel weevils have small ranges, some as tiny as just one patch of forest. “A lot of these species are very specific to certain plants. They don’t eat a variety,” says Cabras. This becomes important if you hope to conserve, or protect, the beetle. “You have to conserve their food plant if you want the beetles to be conserved.“

A Fuller Picture

There’s another reason why Cabras tries to record the scene: “For some of my colleagues, this is the first time they are seeing the species alive.” A lot of descriptions of new species are based on museum collections. So, the taxonomists categorizing and naming species have never seen those species alive or in the wild. They have never seen their habitats or host plants.

This beetle, Pachyrhynchus reicherti, would become important to Cabras’ research. She soon discovered a new species that looked similar.

Cabras uses a powerful microscope to closely examine beetle specimens. 

If possible, Cabras then collects a beetle as a sample so that it can be looked at more closely in the lab. “When you are in the laboratory, it’s the same thingyou have to photograph them. You examine[their anatomy.],” she says. The lab work requires tremendous patience because the beetles are so small.

That’s not all. “It also requires special skills and years of training to do the lab work. You have to train your eyes to look into the microscope, but you also have to train your hands.” Beetles must be dissected, or cut apart, so scientists can see their internal structures. That requires good eyes and steady, steady hands. 

Yet, even with her good eyes and steady hands, Cabras can’t always trust what she sees. Sometimes even she can be fooled.

Weevil Wonders

Jewel weevils are so named because they sparkle like gems. Their elytra, or wing covers, shimmer with an array of colorsfrom brilliant turquoise and shiny gold to pale orange and pink. With such noticeable colors, you’d think they’d be easy targets for predators like frogs, lizards, and birds. But weevils want to be seen. Their colors act as a warning: Don’t eat me. I taste bad.

There’s a word for this in science. It’s called aposematism. It is the advertising by an animal to potential predators that it is not worth attacking or eating. Aposematism can take the form of bright colors, sounds, odors, or other characteristics. These signals are helpful to both predator and prey, since both avoid potential harm.

Cabras knew all about aposematism, but she didn’t realize how much it was going to affect her weevil research.

Chrysopida sp. is a leaf beetle that looks like some jewel weevils.