Analysis of Honeybee
Aggression By
Dylan Voeller and James Nieh I. Principles introduced in this exercise A. Aggression: how they attack B. Defender's perspective:
what to attack D.
Differences between European honeybees and Africanized honeybees C. Results of aggression II. Introduction Honeybees are famous
for many things, including their ability to inflict painful stings. This exercise focuses on honeybee aggression
and uses a video demonstration of honeybee attacks and the kinds of
things that honeybees like to attack.
Perhaps this can help you learn what to avoid in the future!
Although the video and exercise focuses on the commonly found
European honeybee, the behavior of Africanized honeybees is quite similar,
except that their aggressive response is, as a group, more intense. General honeybee aggression Honeybees generally
attack only to defend their colony, but will also attack if they are
seriously disturbed outside the nest.
Common sources of attack stimulus for honeybees include alarm
pheromone, vibrations, carbon dioxide, hair, and dark colors (Crane
1990). This makes sense
because mammals, which are common predators of bees, are usually hairy,
dark colored, and exhale carbon dioxide.
If you think about this you will realize that bees are drawn
towards attacking sensitive areas around the head of a common predator.
Stinging is the
ultimate final act of a honeybee because soon after, she will die. First the bee becomes alerted; she takes on
a guarding stance and protrudes the sting, which recruits other bees
by releasing alarm pheromone. Secondly,
the bee will search for the source of stimulus and orient towards it. Finally she will attack; emitting a high pitched
buzz and making body thrusts towards the source of disturbance. In such a defense response, honeybees rarely
pursue stimuli for long distances (although Africanized bees can pursue
victims for hundreds of meters. If
a sting does occur, the bee will die soon after stinging because the
sting is left behind and the bee disembowels itself in flying away.
Once the bee’s sting is inside a victim, it pumps out more venom
and emits alarm pheromones. During
this time, the stinging bee will spend its dying moments distracting
its victim by flying around its head as if it were going to sting again. Africanized honeybees Africanized honeybee
venom is not more painful or voluminous than normal honeybee venom,
its just that many more bees will sting!
This is because Africanized honeybees are very sensitive to alarm
pheromone (the odors, smelling a bit like banana, which foragers release
from their sting gland and glands located in the head when they are
alarmed) and produce much more of it than temperate honeybees. The threshold for stinging response in Africanized
honeybees is also much lower; only a minor disturbance such as a slight
motion, vibration, or odor is needed.
A study by Collins (1985) showed Africanized honeybees respond
2.4 times faster to alarm pheromone and about 30 times as fast to a
moving target! Once Africanized bees have been stimulated, they are
also much more likely to respond in group attacks.
During such attacks they will sting anything in sight that is
moving and may pursue a source of disturbance for up to a kilometer
(Winston 1992). The rapid defense
response of Africanized honeybees is most likely a result of adaptation
to life in tropical climates, where there is a higher rate of predator
attacks on colonies. These higher
attack rates favor the evolution of rapid colony defense, since successful
nest defenders are able to survive and produce more offspring than those
that are killed off by a predator, such as a badger who is hungry for
honey. The biology of Africanized bees, including their higher level
of aggressiveness, is thought to play a role in their successful invasion
throughout the III. Materials & Methods
A.
Open and view the first bee attack
video.
B.
What are the bees attacking?
C.
What happens when a bee stings?
D.
How do other bees react to the odor
of alarm pheromone?
E.
Open the video of bees stinging a
cotton ball. Does this response
decrease with distance?
F.
Are there any there any other stinging
preferences? Color, hairiness?
IV.
Sample Results (Insert
screenshots of what bees like to sting) V. Sample Discussion Questions
A.
What stimulated the bees to attack?
B.
Once stimulated, what did the
attackers focus on?
C.
Why might the bees show such
an attack preference?
D.
Have you ever seen a bee attack
before or been attacked? If so,
what do you think stimulated the bee’s response?
E.
What are some strategies for
avoiding Africanized bee attacks?
F.
Why changes might be caused by Africanized bees introduced
into an ecosystem in which they weren’t formerly present? VI. Sample Conclusions
Collins, A.M., 1985.
Africanized honeybees in the Third International
Conference on Apiculture in Tropical Climates, International
Bee Research Association: 117-122. Crane, E., 1990.
Bees and beekeeping: science, practice, and world resources. York,
Hunt, G.J., Guzman-Novoa, E.,
Fondrk, M.K., Page, R.E., 1998. Quantitative
trait loci for honey
bee stinging behavior and body size. Genetics
148: 1203-1213. Winston, M.L., 1992.
Killer bees: the Africanized honey bee in the
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