Scientists Discover Honey bees secret world of heat / General Science and Electronics / Forums

Forums

4hv.org :: Forums :: General Science and Electronics

« Previous topic | Next topic »

Scientists Discover Honey bees secret world of heat

Move Thread

LAN_403

Proud Mary

Sun Mar 14 2010, 12:39AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Honey bees secret world of heat revealed
Honey bees precisely control the temperature inside their hives to determine which job their young will perform in the colony when mature, new research has revealed.

By Richard Gray, Science Correspondent,
Telegraph
13 Mar 2010

The secret of honey bees' success has been discovered living deep inside their hives - a special type of bee which acts like a living radiator, warming the nest and controlling the colony's complex social structure.

The "heater bees" have been found to play a crucial, and previously unappreciated, role in the survival of honey bee colonies.

Using new technology that allows scientists to see the temperature inside the bee hives, researchers have been able to see how heater bees use their own bodies to provide a unique form of central heating within a hive.

They have found that these specialised bees, whose body temperatures are considerably higher than other bees in the colony, not only keep the hive warm but also control the social make-up within a colony.

Bees, and other social insects such as ants, share jobs within a colony so each individual has specific role that benefits the colony as a whole.

It is this division of labour that has allowed bees to become so successful as they behave like a highly organised, single "superorganism" rather than a cluster of selfish individuals.

Heater bees are responsible for maintaining the temperature of the brood nest in a hive, where young bees, known as pupae, are sealed into wax cells while they develop into mature bees.

The scientists discovered that the heater bees work to subtly change the temperature of each developing pupae by around a degree and this small change determines what kind of honey bee it will become.

Those kept at 35 degrees C turn into the intelligent forager bees that leave the nest in search of nectar and pollen.

Those kept at 34 degrees C emerge as "house keeper" bees that never leave the nest, conducting chores such as feeding the larvae and cleaning the nest.

Professor JÃ¼rgen Tautz, head of the bee group at WÃ¼rzburg University, in Germany, said this allows the heater bees to control what sort of job a bee will fulfil when it matures and so ensure there are always enough bees filling each role within the colony.

He said: "The bees are controlling the environment they live in to make sure they can fill a need within the colony.

"Each bee in a colony performs a different profession â€“ there are guard bees, nest building bees, brood caretaking bee, queen caretaking bee and forager bees, which are the ones we are familiar with as they leave the colony.

"By carefully regulating the temperature of each pupae, they change the way it develops and the likelihood of the role it will fulfil when it emerges as an adult."

The findings will be revealed later this month in a new BBC series Richard Hammond's Invisible World, where technology is used to give a glimpse into previously unseen worlds.

Thermal imaging cameras reveal how individual heater bees warm up the nest to precisely the right temperature.

By beating the muscles that would normally power their wings, heater bees increase the temperature of their bodies up to 44 degrees C â€“ nearly 10 degrees hotter than a normal bee.

They then crawl into empty cells within the brood nest, transmitting heat to the surrounding cells where the bee pupae are developing. The waxy cells also help circulate the heat around the rest of the hive.

In the past beekeepers have seen these empty cells as undesirable and have attempted to breed queens that did not leave them empty, but Professor Tautz now claims they are an essential part of ensuring the health of a bee colony.

Warmth is essential for bees as they need a body temperature of around 35 degrees C to be able to fly.

The heater bees, which can number from just a few to many hundreds depending on the outside temperature and size of the hive, also press themselves against individual cells to top up the temperature of each pupae to ensure it develops into the right kind of bee.

Professor Tautz added: "The old idea was that the pupae in the brood nest were producing the heat and bees moved in there to keep warm, but what we have seen is that there are adult bees who are responsible to maintaining the temperature.

"They decouple their wings so the muscles run at full power without moving the wings and this allows them to raise their body temperature extremely high.

"Their body temperature can reach up to 44 degrees centigrade. In theory they should cook themselves at that temperature, but somehow they are able to withstand this high temperature.

"By creeping into empty cells, one heater bee can transmit heat to 70 pupae around them. It is a central heating system for the colony.

"Now we know that these empty cells are important, then bee keepers can try to avoid selecting for queens that don't leave these cells empty. It can help to ensure that colonies can regulate their temperature properly and have the right mix of individuals."

Temperature is known to have an influence on the development of young in other animal species.

In crocodiles, the sex of hatchlings is determined by the average temperature of the eggs during a key point in the incubation period, so if they are kept above 34.5 degrees C the offspring will be male.

Many species of fish and turtles also use temperature to determine the sex of their young.

Dr David Aston, chair of the British Beekeepers Association's technical and environmental committee, said: "There has never been a good reason for the presence of individual empty cells across the face of the comb.

"Now Professor Tautz has provided an explanation and beekeepers will look more closely at the brood combs to see if they can observe heater bees at work."

Richard Hammond's Invisible World will begin on BBC One on March 16. The episode with the heater bees will be shown on March 23.

Mates

Sun Mar 14 2010, 01:09PM

Registered Member #1025 Joined: Sun Sept 23 2007, 07:53PM
Location: Czech Rep.
Posts: 566

I have always proposed that it must be some kind of chemicals (pheromones) responsible for the developmental control of social insect. This is very surprising mainly from the point of view that temperature belongs to the most unstable environmental factor (how is ensured cooling during hot sunny summer day?). On the other hand, the fact that it is such a simple factor which can modulate the type of preprogrammed development can open doors for artificial manipulation with the structure of social insect.
For example, evolutionary there must be encoded certain amount of warrior bees â€“ the hive protectors. Such bees mean extra costs for the society and in the man-based honey industry (where the man is the protector) these bees might be substituted by bee workers using some artificial (peltier) heaters/coolers inside the hive â€“ it would lead to more honey and more money

hboy007

Sun Mar 14 2010, 01:42PM

Registered Member #1667 Joined: Sat Aug 30 2008, 09:57PM
Location:
Posts: 374

Mates, this would be to easy, wouldn't it? Bees still have to take care of themselves and a bee keeper can to little to avoid his bees from being attacked by ants, wasps, hornets, mice and so forth. Bees have very elaborate mechanisms to control the temperature. During thickening of honey, they evaporate the water, if it gets too warm, they collect water form puddles, pools and bird baths and use it for cooling. There are always some bees that fan and circulate the air in the hive. Adding or removing heat would to some extent be levelled out without further notice.
Thanks to this article I finally know why sometimes cells remain empty in the comb. In springtime, when fruit trees are in full bloom there are large amounts of collecting bees needed, there are several combs entirely used for breeding and I suppose they are temperature controlled as a whole.

Proud Mary

Sun Mar 14 2010, 01:49PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

This type of research on the social organization of bees makes me question whether it is correct to think of one bee on its own as a discrete 'individual.' Perhaps a bee colony is the single individual, an example of disseminated intelligence.

Perhaps the anthropomorphic bias of political beliefs in the 'individual' and 'individualism' has been projected onto the species, and thus far prevented people from recognizing the swarm as the single individual - the superorganism as the article suggests.

brtaman

Sun Mar 14 2010, 10:50PM

Registered Member #2161 Joined: Fri Jun 05 2009, 03:36PM
Location:
Posts: 247

Great read, Proud Mary, thank you for sharing! What strikes me is this "new" technology which allows them to monitor the temperatures within the beehive. How is it different from any high-res IR thermal cam coupled to fiber? Is it a case of actual new technology, or just someone making a new use for an existing one?

Proud Mary

Sun Mar 14 2010, 11:16PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

brtaman wrote ...

Great read, Proud Mary, thank you for sharing! What strikes me is this "new" technology which allows them to monitor the temperatures within the beehive. How is it different from any high-res IR thermal cam coupled to fiber? Is it a case of actual new technology, or just someone making a new use for an existing one?

Everything has to be bigger, taller, higher, further, stronger, and the very first of its kind in the world of journalism, including science journalism.

I buy honeycombs quite often, and have always wondered why a small number of cells seem not to have been used. Now I know why.

In Britain, we now have a bee catastrophe, with the number of bees in a sad, sharp decline. Any research that might help these splendid, helpful insects to bounce back would be a great blessing.

Nicko

Mon Mar 15 2010, 05:53PM

Registered Member #1334 Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615

This is an interesting subject that beekeepers have been discussing for some time -

- Prof Tautz is well respected as is his unit.

One of my more obtuse qualifications, that doesn't make it onto my CV, is as a qualified beekeeper - I studied at Hadlow College in the UK - once upon a time a European Centre of Excellence until our esteemed government withdrew its funding... When I did my exams (about 15 years ago), this particular topic was not known about. Bees have been studied for many 100s, if not 1000s of years, and we continually learn something new...

I've played with some of my colonies from time to time, using uPs to log exit & entrance rates vs. outside temp etc, but have never investigated the core temperature of a brood box - apart from so called heater workers, there are also air-con workers who hang about at the entrance fanning air into and out of the brood box and equally importantly controlling the humidity. Bees of all types, social & solitary, are fascinating. I can watch a social bee colony on a warm day for hours. What's also not mentioned is that bees can change role throughout their lives, which for workers during the summer months, is not long at all. The complete antithesis of my day job...

Steve Conner

Mon Mar 15 2010, 05:56PM

Registered Member #30 Joined: Fri Feb 03 2006, 10:52AM
Location: Glasgow, Scotland
Posts: 6706

Proud Mary wrote ...

This type of research on the social organization of bees makes me question whether it is correct to think of one bee on its own as a discrete 'individual.' Perhaps a bee colony is the single individual, an example of disseminated intelligence.

There are words to that effect in Douglas Hofstadter's book Godel, Escher, Bach. He was writing about ant colonies, but same thing.

He goes on to argue that our own "individuality" emerges from the "colony" of nerve cells between our ears in the same way.

Nicko

Mon Mar 15 2010, 06:39PM

Registered Member #1334 Joined: Tue Feb 19 2008, 04:37PM
Location: Nr. London, UK
Posts: 615

Steve McConner wrote ...

... Douglas Hofstadter's book Godel, Escher, Bach....

I still have my copy of GEB - the dust jacket has faded from yellow to almost white... Still good for hand-to-hand combat though...

In its time is was like "A Brief History of Time" - one of those books that many people started, few finished and even fewer understood (though many claimed to)... I was in the second group and only inched into the fringes of the third...

Moderator(s): Chris Russell, Noelle, Alex, Tesladownunder, Dave Marshall, Dave Billington, Bjørn, Steve Conner, Wolfram, Kizmo, Mads Barnkob