The vast majority of the world’s 20,000-plus bee species are strict herbivores, relying exclusively on floral resources for sustenance. They have evolved specialized physical and physiological traits adapted for this plant-based diet. However, a few tropical species represent a fascinating exception, having made an evolutionary shift to a carnivorous diet.
The Typical Herbivorous Diet
The standard bee diet is built upon two components collected from flowering plants: nectar and pollen. Nectar serves as the primary source of carbohydrates, providing the necessary sugar for metabolic energy. Pollen is the source of protein, lipids, and other nutrients, used mainly to feed developing larvae and young adult bees.
Digesting pollen, which is encased in a tough outer wall called the exine, requires specialized processes. Bees use a combination of enzymatic breakdown and osmotic shock to extract nutrients through the grain’s pores. The bee gut is colonized by bacteria, such as Gilliamella and Snodgrassella, that assist in breaking down complex carbohydrates. This digestive system is highly adapted for a plant-based diet and is not equipped to process animal protein efficiently.
The Exception: Bees That Eat Meat
Only a small number of stingless bee species, known as “Vulture Bees” (Trigona species), have abandoned the herbivorous diet. Found in tropical regions, these bees use carrion—such as dead fish, snakes, or insects—as their primary protein source instead of pollen. This shift was likely driven by intense competition for floral resources in their environment.
To process this unusual food source, these bees have developed significant changes to their internal biology. Vulture bees possess a unique microbiome enriched with acid-loving bacteria, including Lactobacillus and Carnobacterium, similar to those found in mammalian and avian scavengers. These specialized microbes create an acidic environment in the gut that helps break down the meat and protects the bees from toxins and pathogens. Foraging bees collect carrion fragments, storing them in their hind-leg baskets—structures normally used for carrying pollen—and transport them back to the hive to feed the young.
Interactions: Bees and Insect Pests
While Vulture Bees consume carrion, the vast majority of bees do not eat other insects they encounter. Social bees, such as honeybees, frequently attack and kill pests and predators that threaten the colony, but this behavior is purely defensive, not nutritional. Common intruders, including wasps, hornets, or small hive beetles, are often repelled by guard bees at the hive entrance.
If an intruder enters the colony, bees may use their stingers or employ a unique group defense strategy. This involves a mass of bees surrounding the pest and vibrating their flight muscles to raise the temperature high enough to kill the invader through heat. The dead insect is then removed from the hive as waste, confirming that the bee’s goal is elimination of a threat, not consumption.