In article ,
Tim Tyler writes:
|
| [ various references snipped. ]
|
| Ants consume aphid milk, and consume aphid flesh.

That is undeniable.

| They tend many species of subterranean aphids in their nests:
|
| ``Subterranean aphids seem more restricted in the species of their
| mutualist, for example the aphid Aphis maidiradicis was thought
| to have an intimate association with Lasius niger americana
| (Forbes 1894). However A. maidiridicis has since been seen
| to associate with at least five other ant species from two
| genera (Way 1963) and at least 17 species of aphid have been
| found in the nests of L. niger (Schouteden 1902).''
|
| - http://www.msu.edu/~shingle9/NewFile...teractions.pdf

Firstly, we are talking about the UK, and it is likely that L. niger
varies in behaviour with location. But, secondly and more importantly,
you are extrapolating wildly from evidence (even proof) of association
to the claim you make above. "Association" means just that; further
work is always needed to work out what FORM of association it is.

The chalk blue butterfly is associated with ants, but its association
is entirely different.

| What other properties do you think would be needed for these
| ants to qualify as 'farmers' rather than 'herders'?

In this context, "herding" means providing some benefits to existing
aphid colonies in return for either honeydew or culling; "farming"
involves moving them into a separate environment, providing them with
food and so on. I have seen no evidence that supports even the claims
that L. niger moves aphids to new plants, in order to start new
colonies. Oh, yes, it is CLAIMED.

As far as the references go, there are a lot of potential loopholes
in their methodology, and that might account for why there is such a
discrepancy between their measurements of ant benefits to the aphids
and the crop benefits when ants are excluded. Or it might be even
more complex than that ....

I must print out your earliest reference and read it carefully. It
isn't the clearest paper in the world, and I can't see how they get
from their measurements to their conclusions.


Regards,
Nick Maclaren.