In article ,
Tim Tyler writes:
|
| | Sap suckers:
| |
| | ``Some ant species, such as the common Black garden ants
| | (Lasius niger) found in the UK, farm aphids. They have
| | aphid livestock which they transport between plants and
| | protect from enemies in return for a sugary substance
| | called honeydew, excreted from the aphids as they suck
| | on plant sap.''
|
| All of the references I have seen, and my observation over many
| years, indicate that is at best an urban myth. More bluntly, it
| is just plain wrong. I don't know whether there are any 'farming'
| ant species in the UK - most references are evasive on that - but
| Lasius niger is not one of them.
|
| It does do some desultory herding, but that is about all. I have
| seen one decent reference that indicates that it may assist aphids,
| but the research had a fair number of possible flaws, and it was
| done so long ago that I couldn't check with the author.

Thanks for the references. I have looked for evidence in many parts
of the country, and never seen it, so my estimate is that it can't be
a universal practice. Black bean aphids and L. niger are universal
in the UK :-)

But, yes, I agree that the last paper is strong evidence for herding.
What NONE of those are is evidence for farming, and one of the papers
you quote says that they saw none, either.

| The best first hand evidence I have of UK black
| ants doing more than exploit existing aphids is
| the earth castles they sometimes build to protect
| them from overheating:

They told you why they did it? Please tell more :-)

Seriously, I have occasionally seen this, but have never seen any
justification for the claimed reason they do it. That may be right,
but its rareness makes me think that it isn't.

| http://cat.inist.fr/?aModele=afficheN&cpsidt=15221511
|
| ...has Lasius niger excluding predators from aphid
| colonies:
|
| ``Large predators were excluded by both ant species from the
| aphid colonies, while they were abundant in ant-excluded colonies.''

Let's quote a bit mo

L. niger workers often carried living aphids away from the attended
colonies, whereas P. pungens removed no aphids and disregarded
parasitized aphids, thereby incidentally protecting the parasitized
aphids from predators.

Thus, P. pungens attending T. citricidus largely enhances parasitism
by L. japonicus and its larval survival, compared with when ants are
absent, whereas L. niger exerts no remarkable impact.


Regards,
Nick Maclaren.