Of all the world records profiled on Extreme Science this one has proved to be the most elusive and tricky to keep updated. It seems there are a number of different organisms that hold the record for the "longest lived" and their exact ages are still under investigation. In fact, the only thing we can report for certain is that the records listed here will probably be upstaged by a new discovery in the near future. Below is a listing of what is currently in the literature as some of the oldest organisms still living today:
October, 1999; 250-million-year-old bacteria were found in ancient sea salt beneath Carlsbad, New Mexico. The microscopic organisms were revived in a laboratory after being in 'suspended animation', encased in a hard-shelled spore, for an estimated 250 million years. The species has not been identified, but is referred to as strain 2-9-3, or B. permians.
May, 1995; 40-million-year-old bacteria (Bacillus sphaericus) were found in the stomach of a bee encased in amber. These bacteria were also found in a state of suspended animation and were re-animated in a laboratory.
1997; King's Holly (Lomatia tasmanica) - found in the rainforests of Tasmania. Scientists estimated the age of the plant using a nearby fossil of an identical plant. It was found to be over 43,000 years old! The plants appear to be sterile - incapable of producing flowers and viable seeds. Lomatia is triploid, that is, it has three sets of chromosomes instead of two. Because of this it is unable to sexually reproduce. The clonal thickets reproduce vegetatively by root suckering. Fossil leaves found in a late Pleistocene deposit may be genetically identical to present-day plants. The plant is a rare freak of nature whose origins and age are as yet unknown.
August, 1999; Box Huckleberry (Gaylussacia brachycera) - researchers in Pennsylvania have discovered a living plant that is a remnant of the last Ice Age. Using the known rate of growth if this self-sterile plant, they estimated that this 1/4-acre colony is over 13,000 years old. Researchers are still trying to verify the growth rate to determine is that age is an accurate measure.
March, 2004; Eucalyptus recurva. Also known as "Mongarlowe Mallee" or "Ice Age Gum" it is the rarest Eucalypt in Australia or the world, and is known from only 5 individual specimens. Scientists in Australia are undertaking analyses to determine the exact age of one specimen that is estimated to be 13,000 years old. This aging method also relies on determining the plant's growth rate. Scientists are stilly verifying the growth and performing genetic analyses of neighboring specimens to determine if they are from the same organism.
April, 1980; Creosote bush (Larrea tridentata). Scientists discovered a giant, and very ancient clone of the creosote bush in the Mojave Desert in California they estimated to be between 11,000 and 12,000 years old.
In the photo above are specimens of the 250-million year old bacteria, B. permians. If it can be verified that these were re-animated from a long, long period of suspended animation then they hold the record for world's oldest living organism.
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