kissin’ cous-ants
Using a combination of lenses, the keen-eyed nature photographer
can zoom in on curious "kissing" ant-ics in the world of insects.
A MACRO LENS is a wonderful piece of optics. It opens a window on a world that is seldom noticed,
a miniature world inhabited by insects and other tiny creatures. It enables us to capture these
tiny creatures on film and record facets of their life history.
The standard macro lens of 50mm or 55mm focal length is capable of half life-size reproduction.
For a number of years now, I have been using a combination of lenses which I believe is more
versatile than the macro lens itself. What I have is a 55mm macro lens mounted on a 2X macro-focusing
teleconverter, an accessory piece of equipment.
With this combination, I can get image reproduction all the way up to twice life-size.
What this means is this. Suppose there's an ant measuring 3mm. If I photograph it using
only the 55mm macro lens, I would get an image of the ant measuring 1.5mm. This would hardly
be good enough for most purposes. But when I use the teleconverter as well, I would get an image
measuring 6mm. Now I would have a viable image as this picture could be enlarged without losing
too much quality (or sharpness).
Several years ago, I spotted two ants engaging in what seemed like a long and passionate
kiss. It was the first time I had seen ants doing that, and it was certainly an unusual sight.
Previously, I had seen ants stroking each other's antennae when they met on a trail, but
not kissing.
Hurriedly I brought out my camera equipped with the lens combination described above and
two flash units. My first attempts, however, failed to produce good pictures. So, like a voyeur,
I repeatedly sought out these "kissing ants" and took more pictures until I was
satisfied with the result.
These are Crazy Ants (Anoplolepis longipes), so called because, when disturbed, they
run around in no particular direction. They are about 2 to 4mm long. A common species, they can
be found nesting under rocks, bricks or pots and also under leaf litter.
And the kissing? The ants were actually engaging in trophallaxis ... the mouth-to-mouth
exchange of liquid food between members of a social insect colony.
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Trophallaxis is an important part of life for social insects because, together with the food,
certain chemicals/hormones or micro-organisms necessary for sustaining the colony are also passed around
among the members.
From my observation, it appears that an ant would "beg" to be fed mouth-to-mouth
by signalling to another ant and stroking it with its antennae or feelers. This happens mostly
in the evening, and that was the time I took most of these pictures. But the ants do that at other
times of the day as well.
I have been able to make these observations because Crazy Ants have established a colony
under a stand of bamboo* growing in front of my house.
Apart from Crazy Ants, I have also seen and photographed Weaver Ants (Oecophylla smaragdina)
and a species of paper wasp engaging in trophallaxis.
The Weaver Ants or kerengga, at 8mm to 10mm long, are much larger than the Crazy Ants
and should be easier to photograph. But from my observation they do not go in for trophallaxis
as often as the Crazy Ants.
Also, Weaver Ants give a very painful bite and one needs to be careful not to shake their
nests as this will agitate them and bring out a whole horde of soldier ants.
In the case of the paper wasp, a worker returning from a foraging trip feeds larvae in the
nest by regurgitating food that it has chewed up to a homogenous pulp. However, sometimes the
returning worker wasp is seized by another adult waiting at the nest and is apparently forced
to give it some of the food.
Trophallaxis is a seldom seen aspect of these insects whose life history makes for interesting
reading. I am keeping a lookout for other species which share this habit. With my macro lens and
teleconverter combination I know it won't be too difficult to record their action on film.
* Some time after this article was written, most of the bamboo fell over during a rain storm,
blocking the road in front of our house. The entire family got down to work right after
the rain had stopped, chopping down the rest of the bamboo and clearing the
road ... a tough and messy job, and the fine hairs on the bamboo made our body itch.
(This article was published in GreenWave Vol 2 No 1, June-September 1997).
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