By Jan TenBruggencate
Advertiser Columnist

Hawai'i has a larger proportion of beetles in its array of living things than anywhere else in the world, and there are more kinds of beetles in Hawai'i than any other living thing.

But it's not clear why that's the case, said Allan Samuelson, entomologist and collections manager with Bishop Museum, and one of the state's premier students of beetles.

Most Hawai'i beetles have evolved here into new species — at the latest count, 1,416 of the 2,161 known species of beetles in the Islands are endemic, meaning they are found nowhere else in the world.

Samuelson said it's not certain how their ancestors got here, but researchers have some ideas.

Some are so tiny they could have simply blown with the winds. Some are comparatively large and not good fliers. He figures some may have arrived as eggs or larvae stuck to migratory birds.

"I think with some weevils, there's an association with birds," he said. "These weevils live in the ground, and some of the migratory birds feed in the ground."

Some Hawai'i beetles have evolved to be dependent on particular Hawaiian plants, and in situations where the plants are endangered, the beetles are also at risk.

"They can be highly host-specific," Samuelson said.

It may work the other way around as well, since some Hawaiian plants are pollinated by beetles, and the loss of the pollinators could create a problem for the plant species.

Most folks don't think much about the beetle, that order of six-legged critters distinguished by a pair of modified wings that form a shell-like shield on their backs. But they're all around. They range in size from less than 50th of an inch to more than two inches in length.

Beetles are chewing insects. Some chew wood, some chew leaves, some will chew your carpet, some of them are dung beetles and some are predators. The weevils in your rice are beetles.

The click beetles that are attracted to lights in some Hawai'i homes are outdoor beetles. You know because they'll land and then spring into the air. JoAnn Tenorio and Gordon Nishida, in their Hawaiian insect book "What's Bugging Me?," say the springing is a way to escape from predators.

Most beetles are what Samuelson calls decomposers — they help the natural process of decomposition. The largest of the Hawaiian beetles is a forest animal that feeds on fallen koa and 'ohi'a trees.

And while it might be alarming to many, beetles are also considered delicacies in some parts of the world.

"Some of the largest beetles have larvae that are quite edible," he said.

Samuelson said he prefers them fried.

Jan TenBruggencate is The Advertiser's Kaua'i bureau chief and its science and environment writer. Reach him at (808) 245-3074 or e-mail jant@honoluluadvertiser.com.