Thread subject: Diptera.info :: Pulsating abdomen

Posted by Alvesgaspar on 28-10-2007 16:15
#1
Why many flies, and also wasps, pulsate their abdomens (up and down) when resting? Please forgive the naive question, should be pretty basic for most of you...

Joaquim Gaspar
Lisboa, Portugal

Posted by jorgemotalmeida on 28-10-2007 18:12
#2
The function of abdominal wagging is not fully understood. Even I don?t know the answer. Grin Well, there is an hypothesis that asserts that.. "It looks like wasps talk to their babies about food using vibratory signals."

What I found here: http://www.animalbehavior.org/ABS/Stars/Founders/founders_2001.html

"It is necessary for the wagging abdomen to contact and scrape against the nest surface to make much sound. However, most (80% avg.) AW does contact the nest and produce large vibrations.

If larvae are the intended receivers of the vibratory signal then their presence should effect abdominal wagging. To test this I removed all larvae from the nest for an hour and then replaced them. Sure enough, abdominal wagging completely stopped when larvae were absent, and started immediately when they were returned. (I should note that I was working with naturally occurring single foundress colonies. So there were no other possible adult receivers present.) "

Posted by jorgemotalmeida on 28-10-2007 18:17
#3
"hey my kids what do you want to eat today???" - said the mummy wasp.

"we waaaaanntt Rooooibos!!" -- say the "kindergaten" wasps

"what the heck?? You should not take any more magic mushrooms!" - said her with very strong abdominal wagging.

"hmm.. take it easy, mummy. We are just kidding. Hm... give us an Eresus spider.. they are so juicy. Smile" - reply the tiny wasps..

"ok. I will try to get some... and leave that magic...." - finish her with a very strong pulsation. Smile

end for this non-sense story.
Edited by jorgemotalmeida on 28-10-2007 18:19

Posted by Alvesgaspar on 28-10-2007 18:59
#4
Wow, thanks for the funny explanation Grin I was convinced that was some kind of respiratory or circulatory (heart-beating) phenomenon. But there is a problem with the communication theory: all flies and wasps I saw wagging their bellies seemed to be alone Cool

Joaquim

Posted by jorgemotalmeida on 28-10-2007 22:25
#5
how do you know??? You must dig a lot. Grin

Posted by pierred on 29-10-2007 06:56
#6
Hello,

About Eristalis spp., I think those flies pump with the abdomen when they feed on a flower.
Edited by pierred on 29-10-2007 06:56

Posted by Alvesgaspar on 29-10-2007 23:23
#7
Not only Eristalis, many other syrphids do the same.

Joaquim

Posted by jorgemotalmeida on 31-10-2007 11:11
#8
Alvesgaspar wrote:
Not only Eristalis, many other syrphids do the same.

Joaquim



Also many women do THE SAME when they do Womb Dance. Grin Grin