How Long Can Seeds Live Underground?
Words to know before you read
- Fossils- the remains, or an impression of remains of a plant or animal
that existed in a past geological age that has been removed from the soil
- Paleontology- a science dealing with the life of past geological
periods. Often, people think of paleontology as only the study of
fossils, like dinosaur bone hunters. Paleontologist study much more than bone
fossils, including plants, pollen, spores, and seeds both living and fossilized.
These scientists are called palynologists.
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- Radiocarbon- a chemical analysis tool used by scientists to find out how
old organic materials are based on their content of the radioisotope
carbon-14. Radiocarbon dating is believed to reliably tell the age of organic materials up to 40,000
years old. Also called carbon dating and carbon-14 dating.
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You might be asking yourself, how long can a seed stay dormant? This is a
question that scientists have tried to answer in many different ways.
Scientists have found they can still germinate seeds found in preserved plant
samples in an herbarium. An herbarium
is a collection of pressed plants. The oldest living seed they have found this
way is 90 yrs old. That's probably older than your grandmother!
| Another scientist, William James Beal, started an experiment
in 1880 - that's more than 100 yrs ago! He put seeds into 20 time capsules
and he dug one up every 5 years. He died 25 years after he started the
experiment, so he was only able to dig up 5 time capsules. He found that
some of the 25 year old seeds could still sprout. Another scientist knew
of his experiment and decided to keep it going. For the next 15 years he
dug up another time capsule every 5 years. He was still finding seeds that
could germinate, so he decided to change it to every 10 years. That way he
could make the experiment last longer. The latest time capsule was
unearthed in April of the year 2000, by yet another scientist. The seeds
inside had been buried for 120 years, and some of them could still
germinate. The next time capsule is scheduled to come up in the year 2020,
the seeds will be 140 years old, how old will you be? |
William James Beal
1870-1910 |
To try and find the oldest living seed, some scientists have
been collecting and trying to germinate seeds found in archeological and
prehistoric sites. They thought they had found a 10,000 year old living seed,
because they found it in an animal burrow in layer of soil that was that old.
But some scientists argued that they couldn't really be sure that the seeds were
as old as the burrow they were found in. How could they be sure the seed didn't
fall in while the paleontologists explored the site? So a scientist named Jane
Shen-Miller decided to radiocarbon date old seed pods and germinate the seeds
inside. She now holds the, so far, undisputed record for the oldest living seed
at 3,000 years old.
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