Puzzling Over São Tomé and Principé

A team of scientists whose expertise spans the animal kingdom has returned from the African islands of São Tomé and Principé with a comprehensive animal survey which raises some intriguing evolutionary questions.

How does wildlife reach volcano-born islands separated from the nearest landmass by 200 miles of deep ocean water?

It's easy to imagine that some animals, such as the several species of bats, the eight-inch-long Greef's gecko, or even the 13 species of lacewings that an Academy team of scientists brought back from the islands, flew, rafted, or got blown there by the wind. The arrival of others, like the caecilian, a legless, burrowing amphibian that looks like a bright yellow earthworm, is more perplexing.

Quintino Quade and Tomio Iwamoto with moray eel
Tomio Iwamoto (right) and Quintino Quade with a young moray eel, west coast, Principé.

map:  Principe and Sao Tome\


photo:  Bob Drewes with Schistometopum thomense
Bob Drewes’ with Schistometopum thomense, Muquinque, São Tomé.
Photo: Dong Lin

Tucked back into their cozy laboratories, the scientists are now hard at work comparing these species to those on the nearby island of Bioko and the African mainland to try to piece together this evolutionary puzzle. Their work is cut out for them: the group came back with thousands of specimens including the largest African tree frog (11 cm long) and a tree trapdoor spider, previously known only from one specimen collected in 1895.

Although hot and humid conditions made collecting a lesson in endurance, the survey was "hassle free," according to expedition leader Bob Drewes. From government officials to a young boy who helped the team find a type of frog that had eluded the team for five weeks, the islands' residents were friendly and helpful.

Photo:  Douglas Long and Ricka Stoelting with bat
Douglas Long and Ricka Stoelting at a bat culvert, Praia das Plancas, São Tomé.