January 27, 2006—It's not as though no one's seen baby Kauai cave wolf spiders before (the last sighting was a mere 30 years ago).

But this photo, taken in November and released yesterday by the U.S. Fish and Wildlife Service, marks the first time anyone has ever seen them piggybacking.

It's long been suspected that the spiderlings travel this way—tiny spikes on their legs match up perfectly with forks in the branchlike hairs on their mothers' backs. But it took crawling, camera-wielding researchers in a Hawaii lava tube (a natural tunnel within a hardened lava flow) to deliver the proof.

Discovered in 1971, the roughly half-inch (1.3-centimeter) spiders only exist in caves and lava tubes in the Koloa Basin on the island of Kauai.

Listed on the U.S. Endangered Species List, these hunting (as opposed to web-weaving) spiders are blinder than bats. Unlike their flying fellow cave dwellers, the Kauai cave wolf spiders have adapted so thoroughly to life in the dark that they have no eyes at all.

—Ted Chamberlain

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