Corpse-Loving Bacteria

There are animals and microbes with altered or foreign diets compared to regular species of their type. Vultures and some bee species, such as Arizona spp., have particular acid-producing gut bacteria that protect corpse feeders such as vultures and hyenas from getting sick on rotting meat. While carrion is an abundant source of nutrition, there are barriers that must be overcome for necrophagous animals, Such as how microbes compete to degrade the nutritional quality of carcasses, so most animals cannot get the nutritional value they need from carcasses.

"Vulture bees consuming chicken

Bees typically consume nectar from different flowers, but in South and Central America, bees eat both nectar and dead meat, and some species consume primarily flesh. Many toxin-producing microbes in rotting meat negatively affect animals who consume dead meat. Still, these acid-producing microbes create an extremely acidic environment in the stomach, killing and outcompeting other bacteria. The gut bacteria also end up in the food reserve, helping to preserve it from other microbes that would ruin the food and release toxins otherwise. Specialized immunity and acidic gut pH appear to be essential adaptations to the carrion-eating lifestyle, and their specialized microbiomes have been found to have an important symbiotic relationship with their hosts.

"Vulture Bees gut microbiome including lactobacillus"

This suggests that the animals and the bacteria may have a particular short- and long-term relationship. Host microbiomes can drastically impact host fitness in many vertebrates and invertebrates. They believe this necrophilic bacteria could have evolved alongside the nectar loving bees or that it acted symbiotically to break down carrion into protein giving it an evolutionary advantage. As carcasses have a lot of protein these microbes have become symbiotic to the lives of these animals allowing them to get nutrients most animals could not access.

The vulture bees harbor abundant Lactobacilli and Bacillus species that protect them from toxins and help them get nutrition from the dead tissue. Vultures and other animals have different but similar acid-producing microbes which show the bacterial diversity and symbiotic nature of animals and their microbiome. But who knows which came first, the animals who eat corpses for nutrition or a microbiome that breaks down carrion, allowing them to thrive?

Writer

-Andres Monsalve