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Life Cycles, Growth and Development IDENTIFYING MIMICRY IN NATURE USING BEES AND FLIES OBJECTIVE 
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Comparing bees and flies.
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adaptation · mimicry MATERIALS:
Powerpoint Bees, bee eyesight
and fly mimicry BACKGROUND:
Bees feed on flowers. Bees have powerful defense mechanisms such as
painful sting and group defense. Most predators will avoid bees. Bees are
the ideal model for other insects which also feed on flowers. Most bee
mimics feed on nectar and are the pollinators of plants as well.
Certain flies are bee mimics. By mimicking something else, they
gain some protection and increase their chances of survival.Batesian
mimicry involves a palatable, unprotected species (the mimic) that closely
resembles an unpalatable or self-protected species.
One example is this fly which
looks like a bee. Birds know not to attack a bee as they will be stung.
There are three strategies for fooling predators;
1. To mimic a species that is distasteful or threatening to a predator.
2. To camouflage, blending into the background.
3. To use deceptive behavior whenever a predator is about to attack.
Most of the flies in the family Bombyliidae mimic wasps or bees (Batesian
mimics
of Hymenoptera). However, they have stout bodies and do not have narrowed
waist. Their wings are easily recognized with distinctive vein pattern,
usually dark in color, some with patterns or spots. When at rest, their
wings are flat in outspread position.
PROCEDURE:
1.
Go over the life cycle of bees.
Use the model to point out the long antennae, 2 pairs of wings, and
smaller compound eye.
Larva:
After 3 to days the
eggs hatch into larvae which are fed by worker bees.
A future Queen is fed “royal jelly” a substace secreted from glands
in the heads of worker bees.
A future worker is feed “bee bread” which is a mixture of pollen and
nectar.
Pupa:
At this stage the pupa does not eat, gegins losing its worm shape
and starts to develop the eyes, wings, and legs of a n adult bee.
This stage takes 6 days for a future queen and 11 days for a
worker.
Adult:
The adult bees have different jobs and life spans.
Sterile femaile workers liver 20 to 40 days, tend to young bees and
guard the hive entrance or are field workers that collect pollen, nectar
and water. Drones live 30 to
90 days and their only role is to mate with the Queen.
2.
Introduce the concept of mimicry in insects.
Show the two pictures of difference mimics in the fly group.
There are many species that will try to mimic the coloration of a
bee or wasp.On the photography below (left) these are example of flies
that look like bees or wasps.
On the right are 5 real bees (long antennae) all the rest are flies.
3.
ANSWER KEY FOR FIVE BEES: The
bees are the two on the left in the top row (not the one on the right--the
long thing is its tongue not antennae).
The two on the left on the middle row and the one on the right on
the bottom row.
4.
Have the students make their own “real” bee and “mimic” fly.
Use pipe cleaners, pom pom, glue, play dough, pencil and scissor.
Make sure students realize the two models.
Below the on the left is a bee (long antennae, 2 pairs of wings,
and smaller eyes.
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