THE HONEY BEE

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THE HONEY BEE (Apis mellifera)

Classification

Kingdom : Animalia

Phylum : Arthropoda

Class : Insecta

Family : Hymenoptera

Order : Hymenoptera

Genus : Apis

Species : Apis mellifera

Characteristics of order hymenoptera

  • Insects are social in behaviour.
  • Parthenogenesis is complete
  • After castes present are queens, drones, workers and soldiers
  • Mouth parts modified for biting and sucking
  • Metamorphosis is complete
  • Antennae are short

Examples include bee swamps, ants, gull wasps.

Generally, bees are social insects and live in colonies (large numbers) in bee hives. They show division of labor among the castes for instance;The queen produces other bees.The drone fertilizes the queen.The workers have a number of duties among which include collecting food and cleaning the hive.

External features on the honey bee especially worker include:

  • The head is not fixed on the thorax and therefore it is free to move (mobile).
  • The compound eyes are prominent. In addition to these are simple eyes which are three in number.
  • The antennae are short and segmented.
  • The mouth parts are a modified proboscis which is curved at the distal end. It is used for lapping during feeding and also used for construction, the glossa also modified for sucking.

The features on the thorax include pairs of legs which differ in various aspects as shown below.

The fore leg

The fore leg has a pollen comb located at the end of the tibia. This is used for cleaning pollen off the head.

The middle leg

These legs possess a hair like structure, prong at the distal end of the tibia. The prong is used for scooping pollen grains out of the pollen basket on the hind leg.

Hind leg

The leg is hairy with pollen baskets, which are responsible for carrying pollen grains.

hind leg

These have pollen baskets on their tibia which are used for carrying the collected pollen grain to the hive. They also possess tufts of hairs on the tarsus called pollen brush which are used for cleaning pollen off the body into the basket on the other leg.

Wings:

There are two pairs of membranous and transparent wings. The hind wings are smaller than the fore wings and are interlocked with the latter by means of hooks.

Abdomen:

Features on the abdomen include the first abdominal segment usually being fused with the metathoracic segments. The last segment of abdomen has the stinging device. They have flexible segments which allow the bee to bend, stretch, and expand during breathing and stinging.The abdomen has six segments four of which contain wax glands.

1.The Worker bees:

These are sterile females. They occur in large numbers within the colony. They perform most of the work in the hive and that is why they are called workers.The roles of workers include;

  • They collect food for other bees in the hive.
  • They guard the hive and protect other bees.
  • They protect the hive.

2.The drone bees:

These are male bees. They are larger than workers and are usually very few in the hive. Their role is to fertilize the queen after which they are stung to death by workers.

3.The queen.

This is the fertile female bee. It is usually one in the hive. Its work is to produce all the other bees in the hive.

Life cycle of a bee

Like a butterfly, a bee undergoes complete metamorphosis and differs in length after the larva stage depending on what the larva is fed on. Therefore food will determine the caste to be developed. This is summarized below

pic

Here the larva is fed on royal jelly for 3 days and after on a mixture of pollen grain.Generally the queen bee is the only female in the bee hive and therefore the only capable one to lay eggs.Also it is the largest caste, each bee hive has only one queen. She mates only once in her life time with only one drone. The eggs produced are of two types, both fertilized and unfertilized.The fertilized one develops into queens and workers while unfertilized ones develop into drones. Note that in fertilized eggs, the type of food fed to the larva determines whether the caste will be queen or worker.The queen does not do any work in the bee hive. It is fed and nursed by the workers. It has a sting she uses to kill other developing queens so as to remain the only queen in the hive

The old queen leaves the hive just before the new queen hatches from the pupa and goes away from the hive with a few drones in a swarm.

The drones are the only male bees in a hive. They result from unfertilized eggs of the queen. Only one of the drones and queen go out on a nuptial flight, like the queen, the drone does not do any work in the hive. They are fed by the workers. But in case of food shortage, some of them are killed by workers i.e. stung to death.

The workers on their side do not lay eggs because they areinfertile females. They are the smallest in size among the bees but are the most humorous in the hive. They perform the following duties among others.

  • Cleaning the bee hive by eating away dirt and rubbish.
  • Feeding the old grubs (larva) on honey and pollen.
  • Packing and storing honey and pollen in the cells of the honey comb.
  • Feeding the young grubs on their milk produced by their own salivary glands.
  • Producing wax from their wax glands.vi)Field work to collect food and pollen.vii)Guarding the bee hive against any enemies.

NB The wax produced is used for building the honey combs in which the honey is stored and eggs are laid.The wax is usually formed of sweat after they have eaten too much honey.

Economic importance of bees

  • Source of honey which is a rich food (carbohydrate)
  • Pollinate plants most of which provide food for man.
  • Provide wax used in industry to make candles, varnish, shoe polish etc.
  • Their honey is a drug for many diseases like cough.
  • They are useful specimen for biological studies.
  • The worker bees stings inflict irritation on our bodies

WHY INSECTS ARE BIOLOGICALLY SUCCESSFUL

Insects are mainly terrestrial arthropods that have specialized features and behaviours. These features have enabled the insects to live almost in any part of the world. There are approximately 70,000 different species of insects.

  1. Insects have a high rate of fertility and reproduction. They lay many eggs at once such that when some are destroyed, many survive and develop into adults. They increase in number very rapidly because their life cycles are short. i.e. they take few months or days.
  2. Their bodies are covered with waxy cuticle made of chitin which does not allow water to pass through hence reducing dehydration of insects in different environments.
  3. Insects have a wide range of modification in their mouth parts that are adapted to feeding on different foods. E.g. the adult butterflies feed on nectar while the caterpillars feed on plant leaves. This reduces competition for food.
  4. Some insects have developed wings for flying and all have legs for walking, thus enables the insects to disperse successfully, easily escape from enemies (predators) and as a means of looking for food.
  5. Possession of exoskeleton and some have fore wings hardened to provide mechanical support.
  6. Majority are small in size. Hence they take in little food, occupy small space and escape easily from enemies. Others have variable shapes to fit their mode of life in the locality they live in e.g. cock roaches’ body is dorsal-ventrally flattened for easy passage in narrow path ways (crevices).
  7. Some insects have a variety of colours for camouflage and some spots that have false aggressive and warning appearance to predators e.g. false eyes on the wings of butterflies