Zombie ants clamp on to aerial
vegetation and hang for months spewing the spores of their parasitic fungi, but
researchers noticed that they do not always clamp on to the same part of the
plant. Now the researchers know that the choice of leaves or twigs is related
to climate and that climate change forced the fungi to adapt to local
conditions.
"In tropical areas,
zombie ants bite
onto leaves, but in temperate areas, they bite twigs or bark," said David
P. Hughes, associate professor of entomology and biology, Penn State.
Zombie ants are actually various
species of carpenter
ants that
are infected with a parasitic fungus. About half the species of carpenter ants
can be infected and each species has its own fungus. The zombie ant phenomena
currently occurs around the globe on all continents except Europe. However, a
fossil zombie ant was found in Germany, so they did once exist in Europe as
well.
"They are probably not in
Europe because the forests there are so managed," said Hughes. "They
likely went locally extinct there."
Zombie ant spores fall on ants
from above and the fungus multiplies in the ant body using it as a source of
nutrition. Eventually, the fungus manipulates the ant to climb high into the
branches and clamp on by biting. If an infected ant dies in the colony or on
the ground it has zero chance of infecting another ant, so positioning the ant
bodies where fungi can be widely distributed is essential for these fungi.
"In the late summer and
early fall there are both leaves and twigs everywhere the ants reside,"
said Raquel G. Loreto, postdoctoral scholar in entomology, Penn State.
"But in temperate areas the trees are deciduous and lose their leaves in
the fall. There, the ants bite onto twigs."
No comments:
Post a Comment
You only need to enter your comment once! Comments will appear once they have been moderated. This is so as to stop the would-be comedian who has been spamming the comments here with inane and often offensive remarks. You know who you are!