Honey bees in Israel 370.
(photo credit: Reuters/Amir Cohen)
The honey bee is very common, highly social and important to humanity because it
makes honey and pollinates our food crops. Without this important bee, many
people would go hungry. Young honey bee “workers” spend much of their time in
the colony taking care of baby bees. Older bees work outside on jobs such as
collecting food. In these worker honey bees, a substance called juvenile hormone
is not involved in egg laying. Instead, it determines when the bees stop working
inside and start working outside.
Somewhere along the evolutionary
history of these bees, juvenile hormone stopped doing one job, and started doing
a different job, says Dr. Adam Siegel, a Fulbright postdoctoral research fellow
in the Hebrew University lab of Dr.
Guy Bloch. Fulbright is the US
government's most prestigious and widely-known academic exchange program. The
US–Israel Educational Foundation is responsible for the management of Israeli
participation in the program.
Scientists are interested in juvenile
One way to work on this question is to study the
hormone in a bee that demonstrates some characteristics of solitary bees and
some characteristics of highly social bees.
The bumble bee is a perfect
bee for this type of study, as they live in groups and have an egg-laying queen
bee and worker bees. But the groups are small compared to honey bee groups, and
worker bees have very similar bodies to the queen bee. The workers will also
start laying eggs as the colony gets old. Additionally, the worker bees have a
much less organized system of division of labor. Worker bees will switch from
inside jobs to outside jobs and back again throughout their lives.
the honey bee, the bumble bee is also a very important pollinator of food crops.
Very little is known about what juvenile hormone does in these bees, which
demonstrate an intermediate level of social behavior. The Bloch lab team are
working to figure out what some of the functions of the hormone are in the
bumble bee. “This will help us to understand how this important hormone has
taken on new functions in social systems,” said Siegel. In addition, this work
has very important implications for people.
Many pest insects also use
the hormone to produce eggs.
Because the hormone has to be present at
very specific concentrations to work correctly, farmers can spray pesticides on
plants that include chemicals that work in the same way as the hormone. These
pesticides overload the hormone system in the pest insects and stop them from
In honey bees, these hormone-like chemicals will not stop
the bees from pollinating crops. However, says Siegel, “we do not know what
effects juvenile hormone has on bumble bee pollination. Like honey bees, bumble
bees are a very important crop pollinator. They are especially useful in
greenhouses, because unlike honey bees, bumble bees can work in an enclosed
Israel has a strong agricultural tradition, but limited land
available for growing crops, he says. “Many Israeli farmers use greenhouses to
maximize the use of limited available agricultural land. Our experiments on
juvenile hormone effects on bumble bee behavior will tell us if these pesticides
are safe to use with bumble bee pollinators, or if they will hurt the foraging
bumble bees. This will help farmers in israel and around the world,” the
Fulbright scholar concludes.
VATERITE MYSTERY SOLVED Technion-Israel
Institute of Technology scientists have solved a century-old mystery involving
an unstable atomic arrangement of the chemical compound calcium
Called “vaterite,” the compound forms crystals that are
composed of two different atomic structures, they discovered and wrote in a
recent issue of the prestigious journal Science.
Boaz Pokroy, an
assistant professor in the materials science and engineering department, and his
doctoral student Lee Kabalah-Amitai, explain that the compound of calcium
carbonate and oxygen is the most abundant mineral in nature and appears in
different forms that vary in their spatial atomic positioning. Vaterite is a
specific atomic arrangement of calcium carbonate and in relation to other atomic
arrangements is extremely rare in nature.
Although it is not very
uncommon, vaterites are present in many aspects of our lives, from gallbladder
stones and an essential material in the paper industry to and cement and certain
geological structures. It is found even in meteorites from space.
Haifa scientists are studying the development and formation of vaterites in the
important biological process known as biomineralization. In this process, living
organisms control the production of different minerals on its atomic level. For
example, when a mollusk shell receives a blow that cracks its shell it uses
“vaterite” to repair the damage, a pearl usually has a deep shine (resulting
from a collection of different calcium carbonate) but occasionally (as a result
of a growth error). vaterite forms in the pearl and eliminates its shine, and
fish such as salmon grow vaterite in their ears to aid them with their
For over 100 years, scientists have failed to reach a clearcut
explanation for the atomic arrangement of vaterite.
Pokroy examined crystals found on and within the bodies of small marine animals
known as sea squirts. “This small organism produces a bundle of crystals from
vaterite that are very sharp and relatively large, making them relatively easy
to work with”, the team explained.
“This is why we examined these
crystals; and this is the first time they have ever been studied on the atomic
level. Until now, different scientists tried to find a unified atomic
arrangement for vaterites or determine which of its original structures were the
most accurate. We found that vaterites actually consisted of two different
atomic arrangements that exist in harmony with one another. The second atomic
arrangement was found in a microscopic area (nano-metric – around 40,000 times
smaller than a human hair) and this is the reason it eluded the eyes of
scientists who believed this was a singular structure rather than a dual
The Technion scientists expect their discovery will
facilitate future understanding of the formation mechanisms and stabilization of