Episode Details

Further reading:

How did a tiny bee get to French Polynesia? Eight new species help solve a scientific mystery

Secrets in the canopy: Scientists discover 8 striking new bee species in the Pacific

Canopy specialist Hylaeus bees highlight sampling biases and resolve Michener’s mystery

Scientists discover endoparasitic marine tapeworm trapped in Cretaceous amber

Show transcript:

Welcome to the Patreon bonus episode of Strange Animals Podcast for August 2024!

It’s the start of Invertebrate August, so we have two invertebrate mysteries to discuss today, one mostly solved and one not.

Let’s start with the solved mystery, about a tiny bee. In 1934, three tiny bee specimens were collected in French Polynesia, specifically on a particular type of flower in the Tuamotu Archipelago. The bees really were tiny, only 4 mm long. They weren’t described until 1965, when they were placed in the genus Hylaeus. This is a really big genus with over 500 species that live throughout the world, but the species most closely related to the newly described Tuamotu’s masked bee lives in Australia, New Guinea, and New Zealand.

In case you’re kind of hazy on geography, like me, Australia, New Guinea, and New Zealand are part of what’s called Oceania, a giant chunk of the Pacific Ocean where there’s not a whole lot of land. I mean, except for Australia, which is big. The Tuamotu Archipelago is also part of Oceania, and part of French Polynesia, but it’s really remote. It consists of a spread-out collection of 78 low islands, many of them too tiny to support humans, none of them with a source of fresh water except for rain. They’re tropical and quite beautiful, with many unique animals and plants living on and around them. They’re also almost 2,500 miles, or 4,000 km away from the places where the tiny bee’s closest relatives live.

Even in 1965, scientists had questions about the tiny bee. How did 4mm bees get to such remote islands, and were they even still around? The bees hadn’t been seen in the wild since 1934. Since the Tuamotu Archipelago has suffered from European explorers and missionaries bringing invasive species to some islands, colonization by France, and nuclear weapons testing, scientists worried the bee had gone extinct and that they would never solve the mystery of how it got there in the first place.

Bees are attracted to flowers, and the three 1934 specimens were discovered on flowers, so naturally scientists had been looking for the bees on flowers. But it turns out that in the Polynesian islands, bees mostly hang out in the treetops. Once scientists figured this out, they began discovering new species of bee—eight of them in fact, collected between 2014 and 2019 from various islands in Fiji, Micronesia, and French Polynesia.

All eight species are closely related to Tuamotu’s masked bee, so scientists now have a pretty good idea of how it traveled thousands of miles to get to its French Polynesian home. Its ancestors island-hopped. There are more than 1,700 islands in the Pacific Ocean, many of them barely known to humans.

Researchers think there are probably a lot more species of bee to be discovered in the treetops of Pacific islands, now that they know where to look. With luck, they’ll be able to find Tuamotu’s masked bee too, quietly living out its bee life above the scientists’ heads.

Next, let’s discuss our unsolved mystery. Amber, which is fossilized tree resin, is t