The Nutrient Cycle - Soil: Reflections on the Basis of our Existence - page 92

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Luminescent fungi . Aristotle observed that certain fungi emit a mysterious green light at night. But
even today, we are not sure why. Perhaps the fluorescence comes from the by-products of wood-
decomposing fungi. It could also be a way to attract nocturnal flying insects as spore dispersers.
Another possibility is that the light attracts predators that eat mosquito larvae and other bugs in the
fruit bodies. The light emitted is weak, but can be caught on camera at slow shutter speeds

happened. Perhaps the greatest risk was of irritating a bullet ant when squatting
down. Meyer had been in pain for days after being bitten by one in the arm, and
the symptoms would doubtless be even worse from a bite to more delicate parts.
As it happened, the dung-laying process went without a hitch and I was able to
view the action with binoculars from a comfortable distance. Back at the station I
continued my reading and discovered that I could expect rapid colonisation by egg-
laying flies, but that it could take a few hours for the first dung beetles to arrive. If I
was lucky, my excrement would attract rhinoceros beetles that would fight violent
battles with their horns for the right to lay their eggs there. Rhinoceros beetle larvae
live on maggots that hatch in the excrement. Clearly, I had quite a spectacle awaiting
me, though I decided to keep the experiment to myself initially and not tell any of
the other scientists. I returned after an hour and noted large blowflies dining on the
dung. One had a long neon-coloured abdomen that shone like a gemstone against the
dark forest floor. But there were no dung beetles in evidence yet.

Profitable enterprise . Elk or deer droppings are a familiar sight in Scandinavian forests. In rainforests,
however, animal excrement is rarely seen. Here, dung is an important resource and the males of around
fifty different kinds of dung beetle compete to roll balls of droppings. When the balls are ready, the
beetles perform a characteristic dance to register their surroundings. Then they roll the balls away and
hide them from other males. If the beetles encounter obstacles along the way, they perform the dance
again to orient themselves and make sure they are heading away from the dung pile