cenotes

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Deep in the Mexican jungle, lies an underwater cave called the Angelita Cenote. The pool is 200 feet deep and even contains a separate river that runs along the bottom on the underwater cave. This is due to the different levels of salinity in the water, causing denser water to sink to the bottom.

nature.com
Skeleton plundered from Mexican cave was one of the Americas’ oldest
Rock-encased bone shard left behind by thieves allowed researchers to determine that the remains are probably more than 13,000 years old.

A human skeleton that was stolen from an underwater cave in Mexico in 2012 may be one of the oldest ever found in the Americas. Scientists have now put the age of the skeleton at more than 13,000 years old after analysing a shard of hip bone — left behind by the thieves because it was embedded in a stalagmite.

Cave divers discovered the remains in February 2012 in a submerged cave called Chan Hol near Tulúm on Mexico’s Yucatán peninsula, and posted photos of a nearly complete skull and other whole bones to social media. The posts caught the attention of archaeologists Arturo González González at the Desert Museum in Saltillo, Mexico, and Jerónimo Avilés Olguín at the Institute of American Prehistory in Cancún.

By the time researchers visited the cave in late March, the remains were gone — except for about 150 bone fragments and a pelvic bone that had been subsumed by a stalagmite growing up from the cave floor. On the basis of these bones, the researchers think that the skeleton belonged to a young man who died when sea levels were much lower and the cave was above ground.

Dating techniques

To determine the age of human remains, researchers often measure levels of a radioactive isotope of carbon in collagen protein within bones. But in this case, most of the collagen had been leached out by water while the bones were submerged, making this method unreliable, says Wolfgang Stinnesbeck, a palaeontologist and geoscientist at the University of Heidelberg, Germany, who led the efforts to date the remains.

Instead, Stinnesbeck’s team collected a fleck of the pelvis bone and surrounding stalagmite, which contains a mineral called calcite. The team then dated the rock using the relative levels of uranium and thorium isotopes in the calcite. The deeper into the stalagmite the researchers sampled, the older the dates turned out to be; stone just 2 centimetres from the bone was 11,300 years old. Calcite closer to the bone gave conflicting results, Stinnesbeck says.

The team determined that the skeleton was older than 13,000 years by analysing the rate at which calcite had formed around the bone, and by matching the shifts in stalagmite isotope levels to those in other caves. The findings were published on 30 August in PLoS ONE1.

A diver collects a portion of a cave stalagmite found in cave that contains ancient human bones.

Alistair Pike, an archaeological scientist at the University of Southampton, UK, notes that the stalagmite set over the bone during a time of profound climate change, which could have altered the stalagmite’s rate of growth. He says he is therefore more comfortable considering the bones to be a minimum of 11,300 years old — still “very significant”, he notes.

Ancient company

Few other human remains from the Americas are older than 13,000 years. The skeleton of a teenage girl recovered from a different Yucatán cave was carbon-dated to more than 12,000 years old, and a skeleton found in another submerged cave near Tulúm was deemed to be around 13,500 years old, also using radiocarbon dating.

“They’ve done a really nice job determining the age of this thing,” says David Meltzer, an archaeologist at Southern Methodist University in Dallas, Texas. There is convincing archaeological proof that humans colonized the Americas before 14,000 years ago, but very old remains are precious. “These sites are rare as hen’s teeth,” Meltzer says.

Apart from the Yucatán finds, the next-oldest skeleton from the Americas is that of a 12,600-year-old boy found in Montana, whose sequenced genome places him on a lineage leading to present-day Native American groups. Researchers have sequenced only a few other human skeletons from the Americas that are older than 10,000 years, hindering efforts to unravel the region’s ancient population history.

A stalagmite had grown around a shard of ancient pelvic bone (bottom portion).

Getting DNA from what remains of the Chan Hol skeleton will be hard. A sample sent to one of the world’s leading ancient-DNA labs, the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, did not contain enough DNA, Stinnesbeck says. He hopes to find DNA in the few teeth not taken by the thieves.

The theft still boggles Stinnesbeck, whose team is continuing to study the cave and its remains. The researchers recently reported the discovery of fossils in the cave that are of a new species of peccary2 — a hoofed mammal related to pigs — as well as evidence that the cave’s human inhabitants made fires.

“What would you want with a skeleton? Would you take it home?” Stinnesbeck asks. “If they had known it was very old, maybe just to have a souvenir, to have something special.”

“We went to the police and they did some inquiries,” he adds. “They never came up with anything substantial.”

Summer Themes

Hi everyone!

As promised, here are some of the theme suggestions for the Reaper76 Summer Event!

We don’t want to do set “day themes” like many of these event weeks do, but we do want to provide everyone with some ideas or inspiration.  You’re not limited to these, but some of them might help you get started or get the gears turning.

  • A day at the beach: it’s hard to think of summer without a trip to the beach! Gabriel’s home city of Los Angeles has several great beaches that might give you some inspiration!
    • Some ideas: Which one immediately jumps in the water?  Do either of them like building sand castles?  How does Jack react when seeing the ocean for the first time?  
  • Setting up camp: many people like to go camping in the summer, not just for being outdoors but also to enjoy other activities like hiking, swimming, off-road driving and biking.
    • Some ideas: making smores, building campfires, watching sunrises and sunsets, stargazing
  • Hit the road, Jack: road trips are a quintessential summer pastime. Popular routes include Route 66 and California Highway 1.
    • Some ideas: how do they split driving time, and who is the bad driver?  Who gives bad directions?  How do they split music choices? Motel rooms?  What sights do they go see?
    • Some ideas: when do they take their big Americas road trip?  Who plans the route through Central America, who plans for Southern America?  Where do they visit?  What do they do in Mexico City?  Or Rio de Janiero?  Or Buenos Aires?  Or Santiago?  Do they visit the Amazon in Brazil, the Andes in Chile and Argentina, the cenotes of Mexico and Belize?  Trips across the United States are fun, but consider looking at the wonderful world beyond it - as an opportunity to explore and learn about new places and cultures.
  • We’re all golfers now: lots of sports take place in summer, including baseball, golf, swimming, surfing, and bike races
    • Soccer/fútbol: outside of the US, fútbol matches are popular in the summer.  Would Gabriel and Jack root for a specific team?
    • Lúcioball: which one wants to learn how to play Lúcioball?  Does the other come along and try to play?
  • Just Desserts: lots of great food come into season in the summer - things like watermelons, strawberries, peaches, nectarines, and especially corn (lol).  Ice cream and pies are fun treats in the summer.  Barbecued foods, hamburgers, ribs, steaks, and grilled chicken are all popular.
    • Some ideas: Favorite ice cream flavor?  Favorite fruit?  Who makes the better burger?
  • Welcome to Hollywood: it’s time for summer movie blockbusters!  What kind of movies would they want to see?  Who gets scared in the horror film?  Who wants to see the action flick?
    • Some ideas: What sights does Gabriel show Jack the first time he visits LA?  What are some of their favorite movies?  Do they visit movie sets?
  • Retirement doesn’t suit us: summer often means trips to new destinations.  Where do two supersoldiers go in their time off?  The world is wide with many cool places to visit and see!
    • Some ideas: How do they react to seeing Dorado for the first time?  Or Hanamura?  Which one is the space nerd who wants to visit the Lijiang Tower?  Which one is the history nerd who wants to see Ilios or Giza?
    • Some ideas: Does Gabriel suggest going to Mexico to visit family?  What places does he show Jack?  What foods do they eat, what music do they experience?  
    • Some ideas: who wants to take a trip to China?  Who wants to visit India?  Do they run into junkers in Australia?  What do they think when they visit Numbani in Nigeria for the first time?  How do they react to visiting Gibraltar?
  • Like the stars: did you know fireflies are not found in the western United States? How does Gabriel react to seeing fireflies in Indiana for the first time?
  • Now those are some fireworks: the 4th of July is Independence Day for the United States. Celebrated with barbecues, baseball games, neighborhood and family get-togethers, and fireworks large and small.
  • Summertime Romance: sometimes a love lasts a summer, sometimes it lasts a lifetime (or two).  How do Gabriel and Jack spend over twenty summers together?  Do they do anything special for just the two of them?

Hope these themes help spark your imaginations!   We’re super excited that so many people are interested in participating!  Please feel free to send us any questions or ideas, and best of luck to everyone creating some R76 content for the event!

Remember, the event begins July 4th and ends July 18th!  You can start submitting art, fics, graphics, and content to the tag #reaper76summerevent, or send us a link on the blog!

Have fun, and let the summer sparks fly!

The Signs as Natural Attractions in México.

• Aries: Popocatépetl. Is an active volcano, located in the states of Puebla, México, and Morelos.

• Taurus: Cave of the Crystals. Is a cave in Naica, Saucillo Municipality, Chihuahua, México.

• Gemini: Ría Lagartos Biosphere Reserve. Is a UNESCO Biosphere Reserve in the state of Yucatán, México.

• Cancer: Arch of Cabo San Lucas. Is a distinctive rock formation at the southern tip of Cabo San Lucas.

• Leo: Gran Desierto de Altar. Is one of the major sub-ecoregions of the Sonoran Desert, located in Sonora, México.

• Virgo: Lacandon Jungle. Is an area of rainforest which stretches from Chiapas, México.

• Libra: Monarch Butterfly Biosphere Reserve. Is a World Heritage Site containing most of the over-wintering sites of the eastern population of the monarch butterfly. And is located in Michoacán, México.

• Scorpio: Sistema Sac Actun. Is a cenote located in Tulum, Quintana Roo, México.

• Sagittarius: Tequila Volcano. Is a volcano located near Tequila, Jalisco, in México. This volcano is not dangerous to its nearby communities, which are famous for producing tequila.

• Capricorn: Nevado de Toluca. Is a large stratovolcano in Texcaltitlán, México, México.

• Aquarius: Hierve el Agua. Is a set of natural rock formations in the Mexican state of Oaxaca that resemble cascades of water.

• Pisces: Arrecifes de Cozumel National Park. Is off the coast of the island of Cozumel in the state of Quintana Roo, México.

“The photos are not mine”

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Underground in a Mexican Cenote, with an awful lot of bats.