Paul Beuk wrote:
Andre wrote:
In the light of evolution, it is very well possible that certain diptera-groups (probably closely related to eachother) have developed this behaviour. It could be a mix of reasons. Or the main reason may be digestion, with an extra opportunity to control bodytemperature.
To get a better idea of this, best we can do is to make solid observations in the field, like I suggested above.
I know that both calyptrates and acalyptrates can 'do the bubble'. I cannot recall any orthorrhaphous brachycera and even deep searching my mind I do not recall having seen syrphids do it.
I think it may simply also have to do with the structure of the mouth parts that enable the flies to bubble or not. And that, in its turn, is determined by evolution, as related taxa probably have the same kind of mouth parts, unless evolution took the a step further.
For Brachycera I've pictured this Sepsis sp female (probably Sepsis fulgens with 2 dc but on certain pictures I can see yellow on the legs) :
