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Amber is priced not only in jewelry but also by scientists, too: it can offer
glimpses of past life that other fossils cannot, as it can preserve soft
tissues.
This is how Oregon researchers have found the world's oldest
mushroom, embedded in a 100-million-year-old piece of amber. This is about 20
million years older than any other known mushroom fossils.
The fossil is even more interesting as it contains two parasites, one feeding on
the mushroom and the other feeding on its first parasite.
"I was amazed
enough with the mushroom. But then seeing the parasites was astonishing. No one
has ever seen this three-tier association before." said George Poinar, a retired
entomology professor in Corvallis, formerly of the University of California at
Berkeley, a world leading authority in amber fossils, famous for popularizing
the idea of extracting DNA from insects fossilized in amber (later used in the
movie "Jurassic Park").
The mushroom was discovered in 2006 in Burma by
Ron Buckley, a registered nurse, photographer and collector of amber fossils
from Florence, Ky.
Amber represents fossilized tree resin, a sticky
substance that oozes from both coniferous and some broad-leaved trees. Chemicals
found in the resin are antibiotics that act like natural embalming compounds
(Lebanese cedar resin was used in the embalming of ancient Egyptian mummies) and
creatures trapped in it were wonderfully preserved.
"This shows how far
back mushrooms - and the parasites that infect them - go. The ancient specimen
is similar to pinwheel mushrooms (Marasmius species) that grow on the bark of
modern trees. They dotted the trees 100 million years ago, so they probably were
tasty treats for the dinosaurs to nibble on," said Poinar.
In 2006, the
same team discovered the oldest bee ever, a 100-million-year-old specimen, from
the same area in northern Burma, the place where amber is mined, and also
flowery plants.
"The amber discovery is significant because mushroom
fossils are rare. Ancient mushrooms - the fruiting bodies of fungi - lack bones
or shells, so few survive. So the amber specimen can give us a lot of insight to
what fungal diversity was at this time in the past and gives scientists an idea
about fungi's role in forest ecosystems," added Joseph Spatafora, a fungi
specialist and a professor of botany and plant pathology at Oregon State
University.
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