Honey Bee Anatomy: Hairy Eyeballs and Other Amazing Facts
The more I study honey bees, the more I appreciate how amazing these little creatures are.
There are roughly 20,000 species of bees, but there are only seven species that are categorized as honey bees (in the genus apis). The European honey bee, Apis mellifera, is the most widely known because it has been domesticated for honey production and crop pollination.
What Are the Three Main Parts of a Honey Bee’s Body?
Like all insects, a honey bee’s body is composed of three main parts--the head, the thorax, and the abdomen. There is a “waist” where the thorax joins the abdomen. The abdomen contains bands of yellow-orange and black stripes and ends in a pointy tip.
Just How Small are Honey Bees?
A honey bee is a tiny insect. The females—the worker bees that do the foraging-- are 12 to 15 mm long (about ½ an inch long). They are the smallest of the three kinds of honey bees—the drones (male bees) are slightly larger and the queen bee is larger still.
A worker bee weighs only about 100mg (150th of an ounce). It is so light that it can walk on your bare skin and you may not even feel it.
What Is the Size of Their Brain?
A honey bee’s brain measures just one cubic millimeter—about the size of a sesame seed. Although tiny, it is large compared with the brains of other insects.
Their brains are about ten times denser than a mammal's brain which may explain why, despite their tiny brains, they are very smart.
Does a Honey Bee Have Hairy Eyeballs?
They have five eyes, two large compound eyes, one on either side of their head and three smaller eyes, called ocelli, at the top of their heads.
The compound eyes have thousands of lenses (ommatidia) which most likely give them a pixilated view of the world. Honey bees can see light, motion, and colors.
A short hair grows in the intersections of the compound lenses of the eye. These hairs are believed to detect wind direction and may be used by the bees to stay on course in windy conditions.
The ocelli serve as a kind of navigation system allowing the bee to triangulate its position relative to the sun and thus to find its way home.
How Do Honey Bee Antennae Function?
The antennae are extremely sensitive allowing the bee to feel, smell, and even taste its surroundings. Unlike other bees which have straight antennae, the antennae of honey bees are bent at a 90 degree angle, allowing the bee to rotate its antennae at the “joint” increasing the area it can come into contact with.
How Does a Honey Bee Use its Mouth-Parts?
The mouth (mandible) is attached to powerful muscles, making it a strong weapon against insects like mites or other creatures which try to invade the hive.
The mandible is also used as a cutting tool—it is used to create the honeycomb by shaping the beeswax into neat hexagonal cells.
It can also be used as a cleaning tool to pick up and remove debris from the hive.
The mouth contains a kind of tongue called a proboscis. It is a long coiled hollow tube that works like a drinking straw. The proboscis is unfurled to reach deep within a flower to obtain the nectar. It then curls back up into the mouth until the bee reaches the next flower. It is also used for sucking up drinking water.
And, finally, the mouth is used for eating bee bread--a mix of fermented honey and nectar that is produced by bees within the hive.
How Do They Breathe?
They breathe through holes along the sides of their thorax and abdomen called spiracles. They are lined with muscles which are used to close and open the breathing holes. The spiracles are attached to trachea, breathing tubes.
How Many Stomachs Does a Honey Bee Have?
They have a crop or “honey stomach” above the true stomach, the one used for digestion. When the bee is foraging in the fields, she stores nectar in her honey stomach. There is a muscular valve called the proventriculus between the honey stomach and the true stomach. The bee closes this valve to prevent the nectar from passing into the stomach.
Once the bee has returned to the hive, she ejects the contents of the honey stomach through the mouth.
There are some who jokingly refer to honey as “bee barf.” This is not true because none of the nectar used to make honey comes from the stomach used for digestion.
How Many Wings Does a Honey Bee Have?
They have two pairs of transparent wings-- a larger fore wing and a smaller hind wing--on each side of its thorax. The fore wings and hind wings move together when the bee is in flight allowing her to fly quite fast (12 to 20 mph).
Do Honey Bees Have Knees?
Like all insects, they have six legs—the first pair of legs is shorter than the rear legs.
Each leg is made up of five segments separated by joints. The closest segment to the body, called the coxa, is followed in descending order by the trochanter, femur, tibia, and tarsus.
Have you heard the expression the “bee’s knees”? Bees don’t have actual knees, but they do have joints on each of their legs, connecting each of the leg segments. So that is four joints per leg times six legs for a total of 24 “knees.”
How Do They Clean Their Antennae?
The first pair of legs includes an antennae-cleaner –a pointy little spur located at the fourth joint. When the antennae get covered with too much pollen, the bee inserts an antenna into this joint, closes the hook to the joint, and rubs the antenna clean by sliding it through the gap created by joint and hook.
What Are Pollen Baskets?
The two hind legs each contain a “pollen basket” (corbiculae), little sacs made of long stiff hairs that curve around a flat section of the bee’s rear legs. The bee stuffs pollen grains into these baskets using the stiff hairs on the back of her other legs to scrape the pollen into them and pack them full.
The baskets are transparent so the brightly-colored pollen can be easily seen. These baskets are emptied when the bee returns to the hive. The bees use the pollen to make bee bread. (Pollen contains the protein, lipids and nutrients bees need.)
Do Honey Bees Have Claws?
They have claws at the tips of their feet. This allows them to stand on rough surfaces like bark without falling off. But their feet also have soft pads which provide enough friction to allow them to stand or walk on smoother surfaces. These pads also provide the honey bee with information about the surface it is walking on.
Why Are Their Bodies Furry?
They don’t have fur exactly, but they do have a lot of hair on their bodies and legs. Nearly their entire body is covered with branched hairs, like the needles on the branch of a spruce tree.
Pollen clings to their hairy bodies. .A honey bee uses her hairy front and middle legs like brushes to comb the pollen off her body and pack it into the pollen baskets on her rear legs.
And Lastly, There’s the Stinger.
The stinger is located at the tip of the abdomen. The honey bee is the only kind of bee to have a barbed stinger. The barb at the end of the stinger causes the stinger to become embedded in its target. When she tries to fly away, the tip of her abdomen is ripped away causing her to die.
Inside the tip of the stinger is a venom sac that releases more venom when squeezed. If you are stung by a bee, do not try to pull the stinger out of your skin. Use the edge of a credit card to gently lift the stinger out to avoid releasing more venom into the wound.
I’ve never seen anything like this book before. The book contains photographs of bees taken with an electronic microscope that magnifies up to 5000X, allowing us to see details we have never seen before. The text is minimal, but the photos tell the story. The book starts with full body pictures and then "zooms in” to show specific the specific parts. I like to browse through the book just to enjoy the artistry of the stunning black and white photos and then search through it for the specific details I want to study. (I was actually able to see the hairy eyeballs.)
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© 2017 Catherine Giordano