Biology Reference
In-Depth Information
cohesion of the social unit and regulate the response of colony mem-
bers to changing conditions. For example, isopentyl acetate is a com-
pound produced by the sting gland of worker honey bees that releases
stinging behavior. It is known as the alarm pheromone. Queen honey bees
produce a blend of compounds called queen pheromone. h e main com-
ponent is 9-oxo-2-decenoic acid, which is produced in the mandibular
glands of the head. h is pheromone blend has multiple functions, includ-
ing suppressing egg production and oviposition (egg laying) of workers,
inhibiting the production of new queens by colonies, and serving as an
attractant for males (drones) when queens make their mating l ights. Lar-
vae produce a blend of compounds that they secrete to the body surface
and that stimulate nurse bees to feed them. h e so-called brood phero-
mone also releases pollen-foraging behavior in foraging-aged workers.
Exposure to queen mandibular pheromone and brood pheromone
reduces responsiveness of bees to sucrose solutions. Social pheromones
such as these modulate behavior and response thresholds.
2.5.5 Hormones, Biogenic Amines,
and Stress Modulate Response h resholds
Juvenile hormone (JH) is an important growth regulator in insects and
also is involved in changes in reproductive physiology and behavior.
Juvenile hormone has long been known to af ect age-related changes
in behavior. In honey bees, it is part of the regulatory hormonal net-
work that results in the transition of worker honey bees from perform-
ing tasks in the nest to foraging. Topical treatment of newly emerged
bees with methoprene, a commercially available synthetic form of juve-
nile hormone, results in a signii cant increase in sucrose sensitivity.
Octopamine is a compound produced in the brain that modulates sen-
sitivity to sugar. When bees are fed octopamine in sucrose solutions, they
become more sensitive to lower concentrations of sugar solutions—it
lowers their response threshold to sugar.
Stress also reduces the response threshold to sucrose. Tanya Pankiw
placed newly emerged bees in small tubes to test their sucrose
