Green tree ants swarm over oak blue caterpillars but they are not attacking them. They are drinking a sweet liquid that the caterpillars give off especially to attract the ants. The ants act like living armor, shielding the caterpillar from wasps that might lay eggs on it. The ants and the caterpillars are partners in nature.
Clipping the monarch's wings
Clipping the monarch's wings According to a U.S. research team, genetically
engineered corn released in Canada for widespread use has enough
natural pesticides to kill the larvae of the monarch butterfly.
Research by John Losey at Cornell University found that 44 per cent
of larvae died when reared on milkweed leaves that were dusted with
pollen from genetically engineered corn, and those that survived
were smaller and slower-developing than regular larvae. Corn pollen
can travel at least 60 metres on the wind and may be ingested by
other non-target organisms such as the monarch caterpillars. In
southern Ontario and Quebec, over 400,000 hectares have been
planted with this genetically engineered corn (and 2.8 million
hectares in the central United States) and the numbers are expected
to increase in the coming years. Cornell scientists warn that it is
imperative that further research be done on the environmental
impact of genetically engineered products. A study was done at
Cornell on pollen from "Bt" corn, which is designed to kill the
European corn borer. This corn has been given genes from the
bacterium "bacillus thuringiensis" and produces a toxin which kills
the bugs by bursting their stomachs open. Monarchs, which are
listed on Canada's list of vulnerable species, migrate yearly to
Mexico in the fall and return to breed in the spring. The butterfly
population is estimated at 100 million, but is increasingly
becoming endangered by forest destruction and biotechnology.
Environment Canada believes that it is the destruction of forests
in Mexico which is a more serious threat to the butterfly than the
Bt corn toxin, but adds that Bt is an additional threat to an
already vulnerable species. There are no plans to study the impact
of the corn on monarchs at this point, but there are several
approved field trials which will enable scientists to learn more
about the effects that the corn will have on the monarch
butterfly. 20 MAY 1999
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