Today's Oldest Living Things?
A little over 7,000 years ago bacterial spores were embedded in mud
lining Elk Lake in present-day Minnesota. Scientists from the United
States Geological Survey collected samples of this mud in 1988. In the
laboratory they warmed the spores to surface air temperature and put
them in a nutrient-rich culture where, to quote one of the scientists,
"They grew like crazy!" After 70 centuries they were still alive; they
had survived by living in a frozen state of suspended animation. The
scientists were sure they had discovered the oldest living things. And
they were right, at least for a short time.
In 1992 scientists discovered what could be the largest and nearly
the oldest living thing on earth. The organism is a giant fungus, an
interwoven filigree of mushrooms and rootlike tentacles spawned by a
single fertilized spore nearly 10,000 years ago at the close of the last
ice age. It's come a long way from that single spore, for it now extends
over more than 30 acres in the soil of a forest near Crystal Falls, Michigan,
along the Wisconsin border.
The fungus Armillaria bulbosa is genetically uniform from one end
of its expanse to the other, which is why scientists say it rightly deserves
to be called a single individual. If all its mushrooms and tendrils are
considered together, the fungus weighs about 100 tons, about as much
as the more compact blue whale. The organism survives by feeding on
dead wood and other detritus, spreading outward right beneath the surface
as it senses the presence of nutrients nearby.
To quote one leading fungus researcher's comments on this discovery,
"The catchy part of it is, when you really begin to appreciate how
large this thing is, it's mind-boggling. People usually think of a mushroom
as a little creature, but most of the action of a fungus is underground."
It is almost the world's oldest living thing but not quite.
The Michigan mushroom probably got its start several years after a
California creosote bush sprouted in the East Mohave. This complex
growing in Soggy Dry lake has colonized the area with a circle of
bushes 25 meters ( over 81 feet) in diameter. Any creosote bush that has
become established in an arid area captures moisture so efficiently that
no other plant can grow near, not even another creosote bush. The individual
bush takes over the area by sending out new stems around its
base, to be nourished by the spreading underground roots. All are part
of the single organism. The current circle of creosotes suggests that this
single organism has been growing and expanding for over 10,000
years.
Centuries ago an ailing mastodon stumbled onto the grounds of what
is at present the Burning Tree Golf Course, located about 25 miles east
of Columbus, Ohio. The mastodon came there to die. Perhaps the moisture
of what is still a peat bog felt soothing to its aching body as it lay
down and soon breathed its last.
The carcass of the mastodon was slowly engulfed in the bog and
buried by subsequent deposits of silt and clay. Much of the body was
preserved in its original state. Eons later, in 1989 to be precise, workers
excavating the peat bog to create a small lake between the 11th
and 15th tees uncovered the remains of the fossil mastodon.
Authorities, hurriedly consulted, excavated the mastodon's remains
scientifically. In the abdominal region of the skeleton were the remains
of the mastodon's last meal. It consisted mainly of swamp grass, leaves,
small branches of pine trees, and seeds. The plant material was traced
back to the time of the last ice age. Radiometric dating of the wood
from the mastodon's meal indicated an age of about 11,500 years.
Enclosed in the woody material near the ribs was a reddish-brown
cylinder of malodorous material. Back in the laboratory, analysis of this
foul-smelling, decaying material revealed it to be tens of thousands of
bacteria. These single-celled organisms were identified as two strains
of Enterobacter cloacae, bacteria commonly found in the intestinal
tracts of mammals to aid in digestion. They were cultured by the scientists
because, amazingly, they were still alive!
After searching for, and not finding, the bacteria in 12 soil samples
from the excavation site, the scientists determined that they did not
come from the surrounding soil. A second, "blind" analysis by another
laboratory in Columbus confirmed these negative results. The bacterial
strain definitely came from within the mastodon. The bacteria had
survived because they were sealed under clay and sediment. The bog
water entrapping them slowed down the bacterial growth enough to
cause them to go into a state of suspended animation.
At the moment that these minute bacteria awakened from their
11,500-year nap, they became the oldest living things. Until another
organism, most likely a bacterium or fungus, is discovered in some airtight
bog or layer of permafrost that is more ancient, these E. cloacae
will continue to hold the geriatric record.
[from some book a few years ago- so there could be others discovered- like what was in salt]- fun stuff.
I like the mushroom. |
