A bee species in Costa Rice appears to have a taste for flesh — having evolved an extra tooth for biting meat and a gut that more closely resembles those of vultures.
The University of California Riverside researchers compared gut microbiota of different bee species including the so-called “vulture bees”
They found that vulture bees — which they lured with pieces of raw chicken — have an unusually acidic gut and microbe species linked with the consumption of flesh.
The team believes that the vulture bees developed their meat-eating habits to take out pollen and nectar competition.
A bee species in Costa Rice appears to have a taste for flesh (as pictured) — having evolved an extra tooth for biting meat and a gut that more closely resembles those of vultures
‘These are the only bees in the world that have evolved to use food sources not produced by plants, which is a pretty remarkable change in dietary habits,’ said paper author and University of California, Riverside entomologist Doug Yanega.
His comments included that the diet of vulture honeyes isn’t their only unusual way to eat.
‘Even though they can’t sting, they’re not all defenceless and many species are thoroughly unpleasant.
‘They range from species that are genuinely innocuous to many that bite — to a few that produce blister-causing secretions in their jaws, causing the skin to erupt in painful sores.’
Bumblebees’, honeybees’ and stingless bees share the same microbe-colonized guts.
‘Unlike humans, whose guts change with every meal, most bee species have retained these same bacteria over roughly 80 million years of evolution,’ said paper author and entomologist Jessica Maccaro, also of UC Riverside.
Researchers wondered if the vulture honey bees had a different digestive system to those of their vegetarian cousins due to their very different diets.
To investigate, the team set up bait stations — comprising fresh pieces of raw chicken suspended from branches and smeared with petroleum jelly to deter ants — in locations in both the north and south of Costa Rica.
The baits were successful in attracting vulture bees and other related species that eat carrion — with the team noting that the insects used the little baskets on their hindlegs that stingless bees normally use to collect pollen to store meat instead.
‘They had little chicken baskets,’ said said paper author and entomologist Quinn McFrederick, also of the University of California Riverside.
The team compared the exclusively meat-eating vulture bees with other stingless bees that feed on both flesh and flowers and those that eat only pollen — finding the most extreme changes in gut microbiota among the vulture bees.
‘The vulture bee microbiome is enriched in acid-loving bacteria, which are novel bacteria that their relatives don’t have,’ explained Dr McFrederick.
“These bacteria have a similarity to the ones that are found in actual birds, as well hyenas or other carrion-feeders. This is presumably to protect them from disease.
The researchers were curious to see if vulture bees had a different microbiome than their vegetarian counterparts due to the differences in their diet. To investigate, the team set up bait stations — comprising fresh pieces of raw chicken suspended from branches and smeared with petroleum jelly to deter ants — in locations in both north and south Costa Rica
Among the bacteria found to be present in the vulture bees’ guts was Lactobacillus — which can be found in fermented human food, like sourdough — as well as Carnobacterium, which is known to be associated with the digestion of flesh.
‘It’s crazy to me that a bee can eat dead bodies,’ said Ms Maccaro.
“We might get sick because all of the microbes in meat are competing for our food and creating toxins that can be very harmful to us,”
McFrederick also agreed and said that “the weirdest things in the universe are where many interesting discoveries can be made.” There’s a lot of insight there into the outcomes of natural selection.’
The researchers have completed their initial research and are looking to find out more about how microbes can impact overall health of bees.
All findings were published in mBio.