The rain is pouring down as we arrive in Kinabalu Park, the study area for the first leg of the expedition. About half of the expedition team made the journey to the park headquarters at 1,500 meters today. The remainder will follow us tomorrow, just in time for the opening ceremony. It's a long drive that leads along twisting mountain roads while the buildings passing in view slowly make place for increasingly beautiful rainforest.

By the end of the afternoon the rain finally subsides into a drizzle, but there is still no sign of the spectacular peak of Mount Kinabalu 2,600 meters above us. "That's where the summit should be," says expedition leader Menno Schilthuizen, pointing into the mist. Schilthuizen lived in Borneo for years and knows the mountain well. Despite the bad weather, most biologists can't wait to get out in the field. Just behind the sleeping quarters, spider specialist Peter Koomen finds a web with three species of spider living in it.

A fat brown spider with white stripes on his back dangles in the middle of the web, and near the edge are two small, inconspicuous spiders. "Look, these are the little 'thieves.' When small prey get trapped in the web they try to steal them without getting caught," says Koomen. It's a risky strategy—one wrong step and they end up as a meal themselves.

With the help of a pair of tweezers, the spiders are one by one directed into glass tubes before disappearing into Koomen's "spider hotel"—a cardboard box where the spiders stay until they are carefully photographed and preserved at night.

On the road I meet Hans Feijen, who is holding a butterfly net. A passing girl, seemingly surprised, calls out: "Are you catching butterflies?"

"Not the butters, only the flies!" Feijen replies cheerily. He and his wife Cobi Feijen study stalk-eyed flies, little insects with a remarkable sense of sex appeal. Like their name suggests, their eyes sit on stalks extending sideways out of their heads. The longer a male's stalks are, the more popular he is with females—size matters when you're a stalk-eyed fly. In some species, the male's eyes can be further apart than his body is long! It's the perfect example of how sexual selection can lead to the evolution of puzzling body shapes: males can only grow long stalks if they are in good shape, and so the females that like long stalks tend to have more successful offspring, which in turn favor long stalks.

Unfortunately, after a few good swings of the butterfly net it seems the stalk-eyed flies are still hiding from the rain. Further down the hill, Nicolien Sol collects a fern ally that belongs to the Lycopodiaceae. She explains to a group of colleagues gathered round how fern allies differ from true ferns. And so the afternoon turns into evening, and the first collecting day comes to an end, even before the expedition is officially underway. Feeling content, we settle down in a small restaurant just outside the park. And then suddenly it's there—first faint, then unmistakable. Ever present, but rarely visible. Between the passing clouds, we catch our first overpowering glimpse of Mount Kinabalu's summit, its sharp granite pinnacles reaching for the sky.

Photos: Joris van Alphen

Previously in this series:

Mystery of the Mountain