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Biodiversity hotspot case study: Sao Tomé

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Video transcript

- My name is Dr. Robert Drewes, and I'm chairman of the Department of Herpetology at the California Academy of Sciences. Sao Tome and Principe are isolated, they have never been connected to the mainland. If you think about it, islands that have never been attached to the mainland, anything that lives on them has to cross from mainland Africa across a saltwater barrier, it's called dispersal. And this has happened many many times over many many groups in these two islands. Sao Tome, which is only 30 miles long, is 13 to 15 million years old. The other little one to the north is 31 million years old. These two little islands, for instance, it is thought they have the highest concentration of unique endemic species of birds in the world by unit area. It has giants, it has dwarfs, they have a Begonia that's five meters tall, the other island has the smallest, which is less than a centimeter tall fully in flower. The world's largest sunbird, the world's largest weaverbird, the world's smallest ibis, Africa's largest tree frog, all fascinating phenomena that are easy to see on these islands because they're so small. There are eight species of amphibians on these islands. There should be no amphibians on these islands because they're oceanic. They're surrounded by ocean. And except for freshwater fish, something like a frog would be the last thing you'd expect to cross a couple hundred miles of Atlantic Ocean to get to these. A lot of change is coming. There's oil that's been found within their Exclusive Economic Zone, there are plans for ecotourism, there are plans for an expanded airport, a deep water port, all of this is just not gonna help the environment at all. So we're gonna race to find out what's there and then let the people know how special they are before these changes happen. If you don't know what it is, you're not gonna save it. Well if these kids, when they grow up, don't realize that the birds they're seeing are found nowhere else in the world, not even on the other island, then they're not gonna care.