Greenland Shark

Some demand respect simply because they exist. You may as well give respect to a bucket of dirt.

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On days like today I must give my salute to Archimedes, and not just because he was the greatest scientist of antiquity.  More importantly, it was he who first wrote about the lever, of which the greatest application is the modern corkscrew.  Cheers!

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Did you know the Greenland shark, the world’s largest fish, is very long lived?  One example was recently determined to be between 272 and 512 years old.  How can you do this?  It has no birth certificate or driver’s license.  It was done through carbon dating.  But carbon dating* works only on dead life forms, such as long buried bones or old dead wood.  In the ocean, when anything dies, it is consumed within days or months.  So, you can’t just find dead sharks lying about.  It turns out that within the shark’s eye, there remains some embryonic tissues.  These can be dated, and was.  Amazing.

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Opportunity knocks only once?  Hmm.  Often there is no knock at all. You must look for it!

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By The Way...

* Carbon Dating. Now what is carbon testing?  Basically, because of the sun, radioactive Carbon (C₁₄) is created in all carbon forms on the planet. The compares with normal of Carbon (C₁₂).  The radioactive form decomposes with a half-life of 5730 years.  This means that half of the radioactive form decomposes to the normal form in this time. 

All living things consume carbon-based nutrients.  This means they all have C₁₄ internal to their systems. And over the years, the amount of C₁₄ in every organism is about constant in proportion to its mass. An organism (like the shark or us or a tree) stops absorbing C₁₄ when it dies. So if you take some dead object and measure the ratio of C₁₄ to C₁₂ you can estimate the age of the object.  This is how it’s done.

There are multiple factors about this, such as it must be old enough for the measurement to be meaningful. It cannot be too old to account for errors in measurement.  You must have a sufficient amount of organic material to make the measurement accurate.  An age of 40,000 years is about the max to give reliable dating. It does not work for fossils because they include no original materials.  For Paleolithic measurements the C₁₄ technique does not work at all.