Old Atomic Bomb Tests Help Calculate Whale Shark’s Age


Researchers Calculated a Whale Shark’s Age Based on Cold War-Era Bomb Tests

by Theresa Machemer/Smithsonianmag.com

Whale sharks are the world’s largest fish, recognizable by their white-speckled and striped backs. But as whale sharks age, they also gain stripes on their vertebrae.

The layers, called growth bands, build up like the rings in a tree trunk, so the older a whale shark is, the more bands they have. Now, by using the radioactive chemical signature left behind by Cold War-era nuclear bomb tests, researchers have definitively decoded the big fishes’ bands to figure out how long they live.

The research, published on Monday in Frontiers in Marine Science, settles an ongoing debate over how long it takes each growth band to form; experts previously suggested either 6 or 12 months per band. But getting it right has implications for whale shark conservation strategies. The new evidence points to the longer end of the previous estimates: each band takes about one year to form. And, knowing that, the researchers found that the giant sharks can live to at least 50 years old.

“Basically what we showed is we have a time stamp within the vertebrae,” Mark Meekan, a biologist at the Australian Institute of Marine Science, tells Liz Langley at National Geographic. “We count the bands from there, and ….read more:

Due to the nature of independent content, VT cannot guarantee content validity.
We ask you to Read Our Content Policy so a clear comprehension of VT's independent non-censored media is understood and given its proper place in the world of news, opinion and media.

All content is owned by author exclusively. Expressed opinions are NOT necessarily the views of VT, other authors, affiliates, advertisers, sponsors, partners or technicians. Some content may be satirical in nature. All images within are full responsibility of author and NOT VT.

About VT - Read Full Policy Notice - Comment Policy