Can you be Heard

[grizzly]

I was reading a beekeeping book i got for christmas, and it mentions in there that the bees could "Hear you".

My first thought was, oh no they cant, they can only detect vibrations, but what is the official opinion ? is there scientific fact ?

 

[VEG]

To hear would you not have to have ears?

 

[grizzly]

That would depend on the noise itself, and the frequency being emitted.

For example Elephants have very large ears, used primarily for controlling their temp, however they also communicate via Infrasound, a large proportion of which is Vibration.

 

[Finman]

The scientific fact is that bees make many sounds but their meaning in communication is quite unknown

 

[gavin]

Bee's ears are on their antennae - structures called Johnston's Organs.

Despite what Finnman says, there are clear functions for sound and hearing, the most obvious being one of the ways of communicating distance during the waggle dance:

http://www.springerlink.com/content/m1q43088216g0t56/
http://www.beesource.com/pov/wenner/besa1959.htm

Surely queen piping has a functional role too?

Bees communicate with us too, such as that hiss when we pop the crown board off (which varies according to their humour) and the variations when a colony is preparing to swarm.

Gavin

 

[Finman]

Gavin, are all soud making communication?

 

[gavin]

No - some sound is a byproduct of other activity (wings humming for example). Some is bee-to-bee communication. Some might be bee-to-potential predator communication (but that will probably remain unproved).

G.

 

[Finman]

.
I tried to read here what bees "talks" but I did not get much.

Honeybee sound communication seems not to be popular researching area. It is difficult to find new reports.


http://www.beesource.com/pov/wenner/sci[B]1964[/B].htm

The source seems to be realiable but old, 1964?

This is really old source: 1959. Bulletin of the Entomological Society of America. Vol. 5, No. 3: A paper received after the program was in press:

 

[Finman]

.
This is interesting: http://www.springerlink.com/content/y6757w357q332744/

Summary Sinusoidal 650 Hz vibrations, pulsed in a manner similar to that of the piping sound made by queen honeybees, were applied to hives containing colonies of bees. When the vibrations were applied to four hives containing very small colonies with unmated queens less than one week old, all four colonies swarmed, leaving no bees in their hives. Sixteen slightly larger colonies, also containing queens a few days old, were divided into two groups of eight. One group received vibrations and five of the colonies in it swarmed, each leaving a proportion of its bees in its hive. The other eight colonies did not receive vibrations and none of them swarmed.

 

[raysa]

Elsewhere in Springerlink it suggests that the Johnston's Organ doesn't respond to sounds much above 200Hz, so perhaps other 'hearing' devices come into play for the higher-frequency sounds such as queen piping?
http://www.springerlink.com/content/n6j461628864u162/
I can't find a reference to the frequency range of the vibrodetectors in the legs, but presumably they are more geared to mechanical vibrations rather than airborne sounds.

Ray

 

[Finman]

I can't find a reference to the frequency range of the vibrodetectors in the legs, but presumably they are more geared to mechanical vibrations rather than airborne sounds.

Ray

I read from one research that waggling dance intensity is transmitted via comb vibration to leggs.
http://jeb.biologists.org/cgi/reprint/203/10/1573.pdf

It woud be quite a noise in beehive if 1000 bees try to explain at same time where is a good nectar field.

 

[gavin]

Hi Ray

You may well be right about detectors on the legs being important for higher frequencies, but I wouldn't rule out a role for the Johnston's Organ. The paper you cited described them in a bug of some kind, this one is a comprehensive study in honey bees:

http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1794319

They say that the organ is most efficient between 265 and 350 MHz in bees. I can't tell if they would still work at all at queen piping frequency.

all the best

Gavin

 

[MJBee]

It woud be quite a noise in beehive if 1000 bees try to explain at same time where is a good nectar field.

Hi Finman,
What a lovely mental picture that produces

I can almost hear the boss forager yelling "SHUT UP now one at a time, where is this nectar"

All the best for 2009 - Mike

 

[raysa]

Oh yes, that's a better reference, Gavin.
The frequencies are still very low, though - you'd have thought that creatures as small as insects evolving the use of sound would have gone much higher!

Are we certain there aren't other auditory sensors?

Ray

 

[gavin]

Hi Ray

A bit more reading and things are getting clearer (I'm learning anyway!). Given the frequencies involved and the way bees hold their antennae close to dancing foragers the Johnston's organ is very likely to be important in the bee's interpretation of the dance. You are quite right about the higher frequency of queen piping, and when you think about it, just the presence of piping and not the detailed spatial nature of the call is important. This means that 'listening' to vibrations on the comb might be sufficient.

So, the other hearing organ? It was referred to in the paper Finman cited above. The sub-genual organ, a sound sensor which works at higher frequencies and operates by oscillation of a body sitting in the haemolymph inside the leg!

http://www.springerlink.com/content/ek2eylexjpyvw2fk/

G.

 

[raysa]

Fascinating stuff, Gavin.

The description of the sensor on the leg (as well as the fact that it is in the leg at all) tends to support my earlier assumption that this is more geared to vibrations felt through whatever the bee is standing on rather than airborne acoustics.

I can't help wondering if honeybees may have yet another sensor somewhere that's a bit more like the tympanal 'ears' identified on grasshoppers, aphids, moths and other wee things. I read some references to insect tympanal hearing from Cornell University, but I don't think the honeybee was one of the insects mentioned.

I suppose it all comes down to need. If you're a moth on the nightly dinner-menu of bats, being able to hear the echo-locator is quite important. Whereas a bee probably wouldn't gain a lot from the vocal ramblings of a human with veil on his head!

Ray

 

[Bcrazy]

Not sure if this is applicable but.............

On a bee's antenna there are hairs and spines covering the whole of the antenna which are named 'trichoid sensilla'.

So how does the antenna work as a hearing device?

Bees have adapted a different type of ear from that of other insects.

Travelling sound waves have both pressure and particle movement components.

It has been discovered that bees are able to detect the sounds made by a dancing bee using a receptor this is sensitive to the particle movement component of the sound wave. The antennal flagellum is capable of being deflected by the oscillations of the flagellum induced by the sound are detected by Johnston?s Organ which is a large sense organ located in the pedicle and named after the scientist who first described it.
Because of the attachment across the joint of the pedicel and the flagellum, the sensilla of J O are able to detect vibrations of the flagellum in relation to the pedicel.
Stress can initate changes in the properties to the membrane causing stout hairs on the antenna to send nerve impulses and vibrations to indicate noise.

I hope that makes sence.

Regards;

 

[BKF Admin]

Hi Mo,I was thinking about you reading some of the posts in this thread and thought it was about time you joined the discussion,thanks for your imput.