When Did Humans Reach the Americas?

By Claire Eamer

Now there's a question that opens a can of worms!

A couple of years ago, I wrote a short news article -- Archaeological Find Puts Humans in North America 10,000 Years Earlier Than Thought -- for Hakai Magazine. It was about a new analysis of bones found 40 years ago in the Bluefish Caves in the northern Yukon by Canadian anthropologist Jacques Cinq-Mars. The magazine followed it up with a lengthy and fascinating piece by Heather Pringle: From Vilified to Vindicated: the Story of Jacques Cinq-Mars.

Doctoral student Lauriane Bourgeon's analysis of the bones, particularly a horse jawbone with cut marks on it, appears to confirm Cinq-Mars's original conclusion -- that human hunters were using the Bluefish Caves at least 24,000 years ago, at the height of the last glaciation. At that time sea levels were much lower than today, and people could have crossed to North America from Siberia on the wide, dry, windswept plains of Beringia, a route now blocked by the waters of the Bering Strait.


At the time Cinq-Mars published his first account of the excavation, the prevailing theory said humans arrived in North America from northeastern Siberia about 14,000 years ago at a time when the glaciers were finally disappearing, but when there was still a dry-land link between Asia and North America. They then followed an ice-free corridor between glaciers that led them south to the rest of the Americas. The problem with that theory is the growing body of evidence that no such corridor existed or was inhabitable at that time, as well as another growing body of evidence that people were living well south of the glaciated lands before the glaciers disappeared.

Cinq-Mars's find and Bourgeon's re-analysis of it support another theory: the Beringian standstill hypothesis. According to that theory, humans moved into the dry region linking Asia and North America 10,000 years or more before the great ice sheets melted and the sea level rose. And there they stayed, making a decent living from the animals -- both large and small -- that shared their giant refuge from the ice.

But what about those people living farther south when the ice was still melting? Current thinking suggests they might have arrived by sea, travelling down the west coast of North America, with its rich resources of shellfish and other coastal foods. A report just released dates a cache of artifacts found in Idaho to 16,000 years ago. A joint research effort by Western scientists and First Nations in British Columbia recently found even more startling evidence to support the coastal theory -- 29 footprints left, probably, by a small family walking along a beach 13,000 years ago.

Unravelling the mystery of humans in the Americas is no easy task. Much of the evidence was ground to dust by kilometres-deep ice or flooded by rising seas as the ice melted. But scientists and Indigenous peoples are working on it. It's still a can of worms, but each worm that emerges changes the picture slightly and makes it a little clearer. And a lot more interesting.

Claire Eamer's most recent book is Out of the Ice: How Climate Change is Revealing the Past (Kids Can Press, 2018).

In Case You Needed More Nightmares: I Give You The Cookie Cutter Shark

And, with fewer cookies:

You're welcome.

We're Almost Out of Sand

By Adrienne Montgomerie

Windows, concrete, silicone chips, and even water filtration systems have one thing in common, and it’s getting harder and harder to find: it’s sand.

Can you believe that? The stuff between your toes at the beach, in your bathing suit, in your bag… the stuff that is so hard to get rid of, that sticks everywhere. That sand is running out. It’s getting so hard to find that people are even stealing it, turning the sand business into a crime: a “sand mafia” that will kill to protect their sand supply.
“But what about the desert?” you ask. Well, there are two reasons desert sand can’t be used to make modern products:

1. Desert sand is too round and smooth. River sand, worn down by water has the best shape for making all those products.
2. Deserts are too far from factories. Sand is very heavy; just one cubic meter weighs a ton. That’s as much as small car. And that means the only way it’s affordable to make things from sand is if it comes from nearby — less than 100 km away. 

There is still sand to be mined, but the easy-to-get sand is almost gone. What does this mean for the future? “Sand is actually the most important solid substance on Earth,” says Vince Beiser author of The World in a Grain. “It’s the literal foundation of modern civilization.” Modern life relies very heavily on glass, concrete, and electronics. Reinforced concrete is what made high rise buildings possible. Bridges and huge dams too. Glass is needed for all our smartphones as well as for our solar panels.

We now use more sand each year than we did in the past 100 years, total. “We’re adding the equivalent of eight New York Cities to the world every single year,” Beiser said in an episode of 99% Invisible.

As we search for new sources of sand, we have to look in less easy places, and that means big environmental impacts. Because water’s force shapes the best sand, finding new sand means doing a lot of damage to rivers, lakes, and marshes.

Are there alternatives? Could we use bamboo or recycled materials to make concrete instead? Maybe you will be the materials scientist who finds out.

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Learn more:

“The World is Running Out of Sand,” New Yorker https://www.newyorker.com/magazine/2017/05/29/the-world-is-running-out-of-sand

“Build on Sand,” 99% Invisible podcast https://podcasts.apple.com/ca/podcast/99-invisible/id394775318?i=1000444077857

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Photo of cell phone on sidewalk by olle svensson used under CC BY-2.0 license.
Photo of sand by Ian Strain used under CC BY-NC-ND-2.0 license.

Carpenter Bees

Last weekend I had an unwelcome visitor. A carpenter bee decided that my deck would be a good place to raise a family. I disagreed. If you don’t know about these amazing insects, here goes:

 Carpenter bees are quite different from honey bees. Carpenters don't make honey and they don't live in communal hives. They seldom sting - only the female (queen) is capable of stinging. The males will buzz around you and try to intimidate you, but are actually harmless.

A carpenter bee, without a tool belt.
Photo: Daniel Schwen.

How do you recognize a carpenter bee? If you’re lucky you may also be able to see one wearing a tiny tool belt, with saw, hammer, pliers etc. Otherwise they look a lot like bumble bees, but they have a black shiny bum, instead of a furry one. But the dead giveaway is that they drill beautifully round ½” holes in any piece of wood that they fancy for a nursery. 

This carpenter bee chose a tree.
Photo: ZooFari.

 Here’s a picture of the hole that “my” carpenter bee drilled under the railing of my deck. 

 This is actually the second hole. The light-coloured stuff is Play-doh which I used to fill in the first hole, in a vain attempt to stop her. I chased her off the second time and sprayed the hole with insecticide which evidently she didn’t like.  

Carpenter bees are good pollinators and we need them, so perhaps I should have been more generous. But I selfishly want to keep my deck, and carpenter bees don’t really care. If I had let this queen carpenter alone, she would have drilled out a long (about 6 inches) passage at right angles to the initial hole. She would have alternated filling the chambers of the passage with pollen and eggs. The eggs would have hatched and larvae would have fed on the pollen. Then the larvae would have become pupae which would have become adult carpenter bees, The process would have taken seven weeks to produce a bunch more carpenter bees to continue carving up my deck. 

You can see why I didn’t want my deck to become a carpenter bee nursery.

Snakes at the Seaside and Birds in the Bush

By Claire Eamer

"Snake!" yelled 8-year-old Carys, and dove for the grassy bank beside the trail. She emerged clutching a deeply puzzled garter snake at least 60 centimetres long, with elegant checkerboard markings on its sides and a jagged yellow stripe running the length of its back.

Western garter snake, found at Pipers Lagoon Park, Nanaimo.

The rest of the group -- more than two dozen kids and adults, with an age range from 8 to 80-ish -- crowded around to admire her catch. Our leader, biology professor Tim Goater of Nanaimo's Vancouver Island University (VIU) identified it as a female western garter snake (Thamnophis elegans), almost certainly pregnant, and the largest specimen he had seen at Pipers Lagoon, the small seaside park we were exploring. Western garter snakes have a variable diet, depending on where they live, he explained. Carys's prize catch would specialize in hunting intertidal fishes among the park's rocks and tidepools.

Professor Tim Goater with
a large clam at Pipers Lagoon.

Once everyone had admired the snake, we put her back on the slope beside the trail and watched, fascinated, as she disappeared into the grass and undergrowth in less than a second.

The mixed group of kids and adults wasn't just a casual group of visitors to the seashore. We were students in a class called Explorations of Animal Diversity, one of 10 offerings at this year's edition of Grandkids University. The two-day program is open to kids aged 7 to 13 and to their grandparents or grandparent-equivalents (other senior relatives or special friends).

Carys, left, entranced by birdbanding.

Carys and I (I'm her great-aunt) were in our second year at Grandkids University this year. Her brother, Rowan, was in his third year. He and his special friend, Susan, spent two days in the chemistry lab, making soap, slime, invisible ink, instant ice cream, and pop-bottle rockets -- and learning a considerable amount of chemistry along the way.

Over two days, Carys and I got to see and handle garter snakes both in the lab and in the field, peer at insects through a dissecting microscope, search for animals in the intertidal zone, visit a bird-banding station, dissect a ratfish in search of parasites, and tour VIU's International Centre for Sturgeon Studies.

Master bander Eric Demers shows the wing feathers
of a Common Yellowthroat.

And, at the end of the two days, we all attended a graduation ceremony in the university's theatre. VIU's symbols -- a mace and a beautifully decorated steering paddle -- were formally piped through the theatre to the stage. Then, the VIU registrar, in full academic robes, presented each adult and child with a completion certificate. Kids and adults who had attended Grandkids University for 5 years also received "Masters" medals. (Both Rowan and Carys are determined to get their Masters!)

A female American Goldfinch receives its individualized band.

This is the 11th year for VIU's Grandkids University, and it drew a record 163 participants. Almost a dozen former kid participants have grown up to become VIU students, and a number of the participating adults also take VIU classes. Clearly it's part of the university's recruiting program, but it does more than just generate students.

Carys found a seastar that had lost one arm
and was still regrowing its replacement.

Both the kids and the grandparents learn things -- about the subject they are studying and about each other. For two days, they are equals, experiencing the pleasure of learning something new and interesting. The kids can see that adults don't know everything, but that they can learn. The adults get a chance to see how bright and capable the kids are.

And everyone is reminded that learning isn't drudgery. It's fun.

All photos by Claire Eamer.

The (Missing) Link Between Smartphones and Horns

by L. E. Carmichael

Last weekend, suffering from an airplane cold and soaking my coughing muscles in a hot tub while listening to old episodes of The Daily Show on Sirius on Demand, I heard an incredible story about how smartphone use is causing millennials to grow horns. Here's the link to coverage at the BBC.

Image by Shahar D. and Sayers M., Scientific Reports, 2019/CC BY 4.0

Hacking up my second lung, my first thought in reaction to this story was, well, sure. Because I use the internet regularly and have therefore been exposed to a lot of conversation about the evils of both millennials and smart phones, so the equation

millennials + smartphones = inevitable emergence of inner demons

seemed completely logical.

My second thought, emerging from my life-long exposure to both the sciences and oft-times sketchy science reporting, was that this story was indeed incredible, in the  sense of "impossible to believe."

My second thought was the way to go, as this plain-language article from PBS outlines in some detail.

TL/DR version: the authors of the original study didn't actually measure cell phone use in their subjects, meaning they are blaming a skeletal anomaly on a specific behaviour based on... absolutely no data.

Another red flag? The authors recommend preventative postural education, and one of them runs an online store that sells posture-correcting pillows.

In science speak, that's called a conflict of interest. It doesn't necessarily mean that the results of the research are biased, but it absolutely means that readers should apply an extra filter of critical thinking before accepting them.

I encourage everyone to read the PBS article, because it's a great primer on scientific literacy that provides tools for assessing all science reported in the media. In the meantime, you can probably stop poking your skull in search of horns.

What are your thoughts on this story? Do you have other favourite examples of incredible results to share?