How Have Honey Bees Evolved?
The history of bees dates back 130 million years. Before the bees evolved into the natural pollinators that they are today, flowers were pollinated by the wind, which scattered pollen from plants to flowers in hopes of successful reproduction. However, 99.99 percent of the pollen would possibly be wasted. Bees became the first pollinators as they began to forage for food from plant to plant, collecting and transporting pollen in the process. This began the symbiotic relationship between flowers and pollinators.
When people think of the planet’s natural history, they don’t usually think of the evolution of bees. Yet our buzzing friends, like many insects, are some of the oldest species on the planet. From adopting a diet of pollen to spreading across the entire globe, here’s how honey bees have evolved over time.
The process by which honey bees evolved began somewhere between 80 and 150 million years ago, during the Cretaceous Period. Using an evolutionary tree, also known as phylogeny, researchers were able to shed light on how bees evolved and their relatedness among organism groups. This offered a fresh perspective on bees’ origin.
Bees descended from predatory wasps, which had already been around for millions of years. A certain species of sphecid wasp—an insect family that preys on other insects—began gradually adding pollen to its diet. The protein-rich pollen is an excellent food source for these insects, especially when prey is scarce, so the species eventually came to rely on pollen to feed itself and its young. This eventually resulted in the first bee.
This diversification also closely matches with the pollen-eating family of bees, known as Melittidae. This bee species that appeared in the evolutionary tree feeds on several host plants. The tree also shows explosive diversification rates, showing many bee species per family.
Evolution of Bees: A Timeline
The Late Cretaceous.Bees first evolved during this period. The following are the some of the wasp fossils discovered:
- Pemphredonine wasp. Preserved in amber and found in Myanmar, this wasp fossil dates back to 100 million years ago.This species is one of the closest bee relatives.
- Melittosphex burmensis.This species evolved as a transition between bees and hunting wasps. Also discovered in Myanmar from preserved amber, this specimen also dates back a hundred million years ago.
The Paleogene.During this period, bees began to diversify, migrate, and show signs of eusociality, which forms the early roots of honey bees and their relatives. This means bees have started to form colonies, perform brood care, and divide labor into reproductive and nonreproductive groups. Some fossils found during this period are the following:
- Melissites trigona. These are social, stingless bees preserved in Baltic amber some 42 million years ago.
- Ctenoplectrella viridiceps. These 42 million-year old species are extinct solitary mason bees discovered in the Baltic regions.
The Neogene.Some of the specimen unearthed during the Neogene period are the following:
- Apis nearctica.Found in North America, this is the oldest-known honey bee in the region, found carbon-preserved on fine-grained rock.
- Oligochlora eickworti. A halictid bee fossil preserved in amber.
- Nogueirapis siliceae.A fossil of this stingless bee was found in Mexico.
Evolving with Flowers
The development of bees worked to nature’s advantage—suddenly, there was a far more efficient way of pollinating plants. Many scientists believe that bee evolution coincided with the evolving of flowering plants. As more species of bees fed on pollen, flowers developed bright colors and unique shapes to attract more insects. In turn, some bees—such as the honey bee—developed hair all over their bodies and stiff baskets on their legs to catch more pollen as they flew from flower to flower.
Over the years, adult bees developed physiological and behavioral adaptations to efficiently collect and transfer pollen from flower to flower, which include the following:
- Buzz pollination.Pollen is dislodged from flowers through sound vibrations from flight muscles.
- Pollen-collecting hairs. Bees developed “pollen baskets” and unique hairs to gather pollen and transport it back to the colony.
- Floral constancy. Although most bees are generalists, some bees only specialize in foraging a specific group of flowers.
Similarly, flowers have evolved because of the pressures of pollinator selection. This means they had to transform into another form that most pollinators prefer. For instance, when bees prefer bright-colored flowers, darker-colored ones become brighter over time to keep up with the demand. This can happen between two distantly related flowers through convergent evolution. They may not be closely related, but both have evolved the same form from being pollinated by a similar bee type.
How Do Plants Encourage Bee Pollination?
Plants and flowers “reach out” to bees for pollination through their color, shape, fragrance, size, and of course, pollen or nectar. Determining the number of visits they get from pollinators, these factors include the following:
- Ultraviolet invitations.Ultraviolet flowers attract more visits from bees because the bees are able to see ultraviolet light. On the other hand, red-hued flowers are less likely to get visits as bees don’t see red light.
- Color phases. As flowers develop, they sometimes change color to signal pollinators when they need them most. This increases the bees’ efficiency when pollinating.
- Nectar guides. Flowers exhibit shades, tones, and tints that lead pollinators toward their reward. Think of airport runway lights that lead planes in the right direction.
- Odor. Flowers emit chemical compounds that result in floral odors, ranging from sweet, to musky, to pungent. This enables them to attract pollinators from long distances.
Present-Day Honey Bee
Bees survived the mass extinction that took out the dinosaurs and most of the planet’s large creatures. In the millions of years that followed, bees spread across the planet, adapting and evolving as they went to their different climates.
Today, scientists have identified roughly twenty-five thousand species of bees across the world. Among them, of course, are the honey bees, which are as vital to our planet now as their ancestors were in the Cretaceous Period. Modern beekeepers are devoted to preserving bee populations so these animals can remain members of our planet for years to come.
At present, there are up to twelve species of honey bees worldwide. One of the most common ones—and one of the first domesticated insects—include the western honey bee, or the European honey bee. To this day, western honey bees are the primary species beekeepers maintain for pollination and honey production. In fact, these bees are found in every continent except Antarctica.
Differences between Bumble Bees and Honey Bees
It’s easy to distinguish honey bees from another common bee species, the bumble bees, from their names alone. Honey bees are the kind that we domesticate to produce honey for the colony and our own consumption. On the other hand, bumble bees are bee species that make little honey and are known for their loud buzzing sound. While they work differently, both bees contribute to the environment by pollinating flower after flower. Here are other key differences between the two bee species:
- Honey bees are more cooperative, while bumble bees are more independent.
- Honey bees nest aboveground while bumbles burrow underground to create their nests.
- Bumble bees are plump, round, and furry, while a honey bee is slimmer and has a more distinctive head.
- A honey bee is more likely to live longer than a bumble bee, due partially to its ability to cooperate within the colony.
- A honey bee stings only once, while a bumble bee can sting multiple times.
- Honey bees do not hibernate, while bumbles can hibernate for up to nine months!
- Bumble bees are more effective pollinators as they tend to bumble around and pollinate as many plants as they go. Honey bees, on the other hand, only concentrate in one area at a time.
If the mesmerizing world of bees has caught your interest, consider keeping bees in your own backyard. Humans have been beekeeping for more than nine thousand years now, as evidenced by cave paintings of honeycombs—and even traces of honey on pottery—found in north Africa, England, and the Balkan Peninsula. Today, we rely on it in more ways than one.
Beekeeping is a fun, productive hobby that anyone can enjoy. Aside from collecting honey and beeswax, beekeeping offers a great impact on your neighborhood’s ecosystem and teaches you to become a good and patient gardener. Pick up a honey bee starter kit, and see for yourself all the wonders these creatures have to offer.