In a forest in Costa Rica, a strange, little-known breed of tropical stingless bee has been found. The vulture bee (Trigona necrophaga) evolved an extra tooth to bite flesh and a gut more like a vulture than a bee.
All other known bees in the world eat pollen and nectar, and their own honey. Bees don’t eat meat, at least not until now. It is thought this aberration may have arisen due to intense competition for nectar.
These vulture bees have evolved to eat carrion. Their gut microbes help them digest meat.
A team of entomologists recently set up chicken bait in the forests of Costa Rica to learn more about these meat-eating bees. They gathered a collection of vulture bees and analyzed their guts and genetics.
Doug Yanega, an entomologist at University of California, Riverside, and co-author of the paper that was a recent university press release, commented that these are the only bees in the world that have evolved to eat foods not produced by plants. He considers it a remarkable change in dietary habits.
Co-author Quinn McFrederick is a co-author of the study and is a UC Riverside entomologist. According to him, the traditional pollen baskets on the back legs of honeybees have been repurposed to chicken baskets now.
Honeybees, bumblebees, and stingless bees have all had the same five core microbes for around 80 million years of evolution, according to Jessica Maccaro, a UCR entomology doctoral student. The scientists wanted to study how bee guts, equipped with these five microbes, cope with pollen swapped out for raw chicken and nectar swapped for blood.
This 1:02-minute video by Wiki4All shows vulture bees in action:
They traveled to Costa Rica and hung raw chicken from branches, smeared with petroleum jelly, and compared vulture bees with strictly vegetarian bees, and bees that only sometimes eat meat, to study the bacteria in the insects’ guts. These differed substantially, according to a study the team published in the American Society of Microbiologists' journal mBio.
The carrion-eating bee guts had a microbiome built to break down meat, with acid-loving bacteria like Lactobacillus and Carnobacterium. The other bees do not have these protective bacteria which are like that found in actual vultures, hyenas, and other carrion-feeders.
Despite eating meat, their honey is still sweet and edible. The meat is stored in special sealed off chambers for two weeks before the bees access it, and the chambers are kept separate from where the honey is stored, according to Maccaro, who finds it crazy that a bee can eat dead bodies.
Another surprise about these bees is that they are not all defenseless, even though they can’t sting. They range from innocuous species of bees to biting bees, some with blister-causing secretions in their jaws, which can cause skin to erupt in painful sores. Some species are utterly unpleasant, according to Yanega.
According to McFrederick, the weirdest things in the world can lead to lots of interesting discoveries. The team plans to delve deeper into vulture bee microbiomes, hoping to learn about the genomes of all bacteria, fungi, and viruses in their bodies. A bigger goal is to learn more about the larger role microbes play in overall bee health.
This is certainly a fascinating if strange development in the world of bees.