The Honey Bee Body

Honey bees have many characteristics common to all insects. Insects have a hard outer covering called an exoskeleton, rather than an internal skeleton like vertebrates. The exoskeleton, which is made of a material called chitin, helps to protect the internal organs of the insect and helps prevent desiccation (drying out). In order to grow, the insect must shed the exoskeleton.

Insects have three body regions: the head, thorax and abdomen. The head contains the sensory organs, and appendages for ingestion. The thorax contains the appendages for locomotion, the legs and wings. The abdomen contains the organs for digestion and reproduction.

Honey Bee Anatomical Characteristics

Abdomen. The honey bee abdomen is composed of nine segments. The wax and some scent glands are located here in the adult. The sting is contained in a pocket at the end of the tapering abdomen in adult females.

Antenna(e). The form of the antenna in insects varies according to its precise function. The antennae are feathery in male moths, elongated in the cockroach, short and bristle-like in the dragonfly, and bead-like in the termite. In honey bees, the segmented antennae are important sensory organs. The antennae can move freely since their bases are set in small socket-like areas on the head. Each of the antennae are connected to the brain by a large double nerve that is necessary to accommodate all of the crucial sensory input. The tiny sensory hairs on each antenna are responsive to stimuli of touch and odor.

Eye(s). Honey bees and people do not see eye to eye. Although honey bees perceive a fairly broad color range, they can only differentiate between six major categories of color, including yellow, blue-green, blue, violet, ultraviolet, and also a color known as "bee's purple," a mixture of yellow and ultraviolet. Bees can not see red. Differentiation is not equally good throughout the range and is best in the blue-green, violet, and bee's purple colors.

Like most insects, honey bees have compound eyes that are made up of thousands of tiny lenses called facets. Scientists think that each facet in a compound eye takes in one small part of the insect's vision. The brain then takes the image from each tiny lens and creates one large mosaic-like picture. This image is somewhat analogous to the image produced on a television screen, in which the "picture" is essentially a grid composed of dots of light. The advantage of the compound eye is its ability to detect movement. Honey bees can easily differentiate between solid and broken patterns, but show a preference for broken figures. Related to this, bees respond more readily to moving flowers than to stationary ones. Therefore, their eye is better adapted for movement perception than for form percep tion.

Honey bees also have three smaller eyes in addition to the compound eyes. These simple eyes or "ocelli" are located above the compound eyes and are sensitive to light, but can't resolve images.

Head. The honey bee head is triangular when seen from the front. The two antennae arise close together near the center of the face. The bee has two compound eyes and three simple eyes, also located on the head. The honey bee uses its proboscis, or long hairy tongue, to feed on liquids and its mandibles to eat pollen and work wax in comb building.

Leg(s). The honey bee has three pairs of segmented legs. The legs of the bee are prima rily used for walking. However, honey bee legs have specialized areas such as the anten nae cleaners on the forelegs, and the pollen baskets on the hind legs.

Mandible(s). T he honey bees have a pair of mandibles located on either the side of the head that act like a pair of pliers. The mandibles are used for any chores about the hive that require grasping or cutting, such as working wax to construct the comb, biting into flower parts (anthers) to release pollen, carrying detritus out of the hive, or gripping enemies during nest defense.

Proboscis. The proboscis of the honey bee is simply a long, slender, hairy tongue that acts as a straw to bring the liquid food (nectar, honey and water) to the mouth. When in use, the tongue moves rapidly back and forth while the flexible tip performs a lapping mo tion. After feeding, the proboscis is drawn up and folded behind the head. Bees can eat fine particles like pollen, which is used as a source of protein, but cannot handle big particles.

Pollen Basket(s). A smooth, somewhat concave surface of the outer hind leg that is fringed with long, curved hairs that hold the pollen in place. This enclosed space is used to transport pollen and propolis to the hive. Also called a corbicula.

Pollen Press. Once the bees have gathered the pollen, they move it to the pollen press located between the two largest segments of the hind leg. It is used to press the pollen into pellets.

Rakes and Combs. Structures on the legs used to collect and remove pollen that sticks to the hairy bodies of honey bees.

Stinger. The stinger is similar in structure and mechanism to an egg-laying organ, known as the ovipositor, possessed by other insects. In other words, the sting is a modified ovipositor that ejects venom instead of eggs. Thus, only female bees can have a stinger.

The sting is found in a chamber at the end of the abdomen, from which only the sharp -pointed shaft protrudes. It is about 1/8-inch long. When the stinger is not in use, it is re tracted within the sting chamber of the abdomen. The shaft is turned up so that is base is concealed. The shaft is a hollow tube, like a hypodermic needle. The tip is barbed so that it sticks in the skin of the victim. The hollow needle actually has three sections. The top section is called the stylet and has ridges. The bottom two pieces are called lancets. When the stinger penetrates the skin, the two lancets move back and forth on the ridges of the

stylet so that the whole apparatus is driven deeper into the skin. The poison canal is en closed within the lancets.

In front of the shaft is the bulb. The ends of the lancets within the bulb are enlarged and as they move they force the venom into the poison canal, like miniature plungers. The venom comes from two acid glands that secrete into the poison sac. During stinging, the contents of the alkaline gland are dumped directly into the poison canal where they mix with the acidic portion.

When a honey bee stings a mammal, the stinger becomes embedded. In its struggle to free itself, a portion of the stinger is left behind. This damages the honey bee enough to kill her. The stinger continues to contract by reflex action, continuously pumping venom into the wound for several seconds.

Thorax. The thorax is the middle part of the bee and is the anchor point for six legs (three pair), as well as two sets of membranous wings in the adult. Pollen baskets for carrying pollen back to the hive are located on the hind legs.

Wax Gland(s). Four pairs of glands that are specialized parts of the body wall, which during the wax forming period in the life of a worker, become greatly thickened and take on a glandular structure. The wax is discharged as a liquid and hardens to small flakes or scales and sits in wax pockets. The worker bee draws the wax scales out with the comb on the inside hind leg. The wax scale is then transferred to the mandibles where it is chewed into a compact, pliant mass. The beeswax is then added to the comb. After the worker bee outgrows the wax forming period, the glands degenerate and become a flat layer of cells.

Wing(s). The honey bee has two sets of flat, thin, membranous wings, strengthened by various veins. The fore wings are much larger than the hind wings, but the two wings of each side work together in flight. Just flapping the wings does not result in flight. The driv ing force results from a propeller-like twist given to each wing during the upstroke and the downstroke.