Scientists Say Greenland Sharks May Live 400 Years

NOAA, Flickr // CC BY-2.0
NOAA, Flickr // CC BY-2.0

Get ready to feel like a baby: There may be sharks alive today that are older than the United States. Like, much older. Researchers found a Greenland shark that’s around 392 years old—and 27 others with an average age of 272 years old. They published their findings today, August 11, in the journal Science. 

Young or old, Greenland sharks (Somniosus microcephalus, literally “tiny-headed sleeper”) are extraordinary creatures. They’re the second-largest carnivorous sharks in the world, reaching 2500 pounds. Their teeth are shaped and angled to remove plugs of flesh from their prey, and their own flesh is poisonous. 

Even so, Greenland sharks, like most sharks, present no risk to humans. They’re incredibly slow swimmers and live deep, deep down in the icy waters of the Arctic Ocean. These qualities make them both fascinating to scientists and tricky to track and study. And without data, it’s hard to argue that the sharks need protection.

Julius Nielsen

Previous studies had already found these sharks to have astonishingly long lives. The last estimate, based on a shark caught in 1952, concluded that they could live to be at least 200 years old. 

Science has come a long way since the 1950s, and researchers decided it was time to check again. Fortunately, they had access to a good number of Greenland sharks; unfortunately, that’s because those sharks had been accidentally caught in fishing nets and scientists’ long lines between 2010 and 2013. All 28 female sharks used in the study had been fatally injured by the time they landed onboard—some by other sharks, and some by fishing equipment—and so all were euthanized. After the sharks’ deaths, researchers measured each shark and took tissue samples from the lenses of its eyes. 

The scientists used radiocarbon dating on the samples to see if they could age the sharks. Once again, they had good data thanks to a bad situation—in this case, nuclear warfare. Scientists have known since the 1950s that nuclear bomb tests leave permanent molecular marks on sea creatures. Consequently, the appearance of bomb-related changes in an animal’s tissue can be seen as a sort of time stamp. But because these changes persist, even animals born after any given bomb can be marked by it if the animals they eat were alive during the test. 

By combining this information with the sharks’ body measurements, the scientists were able to estimate each animal’s approximate age. The youngest sharks sampled were less than 10 feet long and under 100 years old. These were mere pups for Greenland sharks; the data suggested that these animals don’t even reach sexual maturity until they’re around 150 years old. 

The oldest two sharks were 16 feet long apiece, and the scientists estimated their age at 335 (plus or minus 75 years) and 392 (plus or minus 120 years). Considering these averages, the researchers say, a conservative estimate of the shark’s longevity would put them at about 272 years old—still making them the oldest vertebrates on the planet. 

Given these astonishing findings and the threats posed to Greenland sharks by commercial fishing, the authors write, it’s time we start thinking about how to protect them.

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The Tower of London Welcomes New Baby Ravens for the First Time in 30 Years

Some of the baby ravens born at the Tower of London
Some of the baby ravens born at the Tower of London
Tower of London Twitter (screenshot)

There are some new residents at the Tower of London. They're only about 11 inches tall, are very noisy, and eat rats for breakfast, lunch, and dinner. Fortunately, they're also adorable—not to mention protected by legend.

On May 17, the Tower of London announced that their breeding pair of ravens, Huginn and Muninn, had welcomed four healthy chicks, the first born at the Tower since 1989. The ravens are part of an unkindness that's been located at the Tower for centuries as a sort of protective asset. According to legend, the Tower must always have ravens, or both the Tower and the kingdom will fall. It's not exactly clear when the legend began, but according to the Tower, Charles II decreed there must always be six ravens present.

Huginn and Muninn are newer additions, having arrived at the Tower in late 2018, and they weren't expected to breed this spring. So it was a surprise in mid-April when the devoted Tower Ravenmaster, Yeoman Warder Chris Skaife, noticed something exciting going on. "My suspicions were first piqued that we might have a chance of baby chicks when the parents built a huge nest suddenly overnight and then almost immediately the female bird started to sit on it," Skaife said in a Tower press release. On April 23, Skaife noticed the birds flying to the nest with food, but it was only this week he was able to get close enough to see the four healthy chicks. The sight delighted him: "Having worked with the ravens here at the Tower for the last 13 years and getting to know each of them, I feel like a proud father!"

The chicks have grown quickly, already quadrupling in size since they were born, and eat a diet of quail, rats, and mice the Ravenmaster provides. The raven parents have an egalitarian feeding arrangement: Huginn, the male, preps the food and passes it to Muninn, the female, who feeds it to her tiny chicks.

The plan is for one of the chicks to stay at the Tower and join the rest of the ravens there. "As the ravens started to hatch on the 23 April, St. George’s Day, the raven that will be staying at the Tower will be called George or Georgina in honor of the occasion," the Tower explained in a press release. According to The Telegraph, the breeding program at the Tower kicked off in response to a decline in the number of legal raven breeders in the UK.

The last raven chick born at the Tower was Ronald Raven, born May 1, 1989. In his 2018 book, The Ravenmaster: My Life with the Ravens at the Tower of London, Skaife wrote that "a baby raven looks a bit like a grotesque miniature gargoyle, but then you see them grow and develop ... It really is wonderful."

The baby ravens born at the Tower of London in 2019
The baby ravens born at the Tower of London in 2019 making some noise
Yeoman Warder Chris Skaife

Dozens of Donkeys, Mini-Donkeys, and Baby Donkeys Are Looking for New Homes

iStock.com/huggy1
iStock.com/huggy1

Cats and dogs aren't the only rescue animals that need permanent homes. At the Humane Society of North Texas (HSNT), there are over 60 donkeys, miniature donkeys, baby donkeys, and Thoroughbred horses up for adoption, the Cleburne Times-Review reports.

Many of the equines at HSNT's ranch in Joshua, Texas came from owners who had to give them up, and others were transferred from different animal rescue groups. As part of the ASPCA’s Help A Horse Home Challenge, HSNT is hosting events to help find new homes for its horses and donkeys.

Between April 26 and June 30 this year, the ASPCA is challenging equine organizations to adopt out as many animals as they can. The groups that see the biggest increases in adoptions between this year and last year's Help A Horse Home Challenge will share $150,000 in grant funding. On May 18 and June 8, HSNT is holding open houses at its ranch for anyone interested in adopting an animal. The events will also be used as opportunities to educate the public about the demands of equine ownership.

If you're not free to swing by one of HSNT's open houses, you can still apply to adopt a horse or donkey. Interested owners can fill out and submit this form [PDF] to equine@hsnt.org. And if you'd like to spend time with baby and mini-donkeys without taking one home, HSNT is also looking for volunteers.

[h/t Cleburne Times-Review]

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