How Do We Know the Moon?

“‘I know the moon,’ said the fox”

My colleague read this title line aloud from a children’s book recently, as part of a staff training. At first, I was just as enchanted with the story as she was. The fox goes on to describe how the Moon is like a rabbit that he can chase across the night. I nodded at this description. Long ago I encountered a lovely retelling of an Ojibwe story called Rabbit and the Moon. In an act of friendship and generosity, Crane carries Rabbit to the Moon, since Rabbit cannot jump that high. Whenever I see a full Moon, I try to pick out the shadows that hint at Rabbit’s long ears. I also see a rabbit in the Moon.

Can you see a rabbit in the moon? I see him looking up to the left, with long ears at the top right. Photo by Emily Stone. 

The moth disagrees with the fox, though. They see the Moon as a great cocoon. The owl knows the Moon as light shining out of a window. The bullfrog sees a lily pad floating on the surface of a pond. The language is poetic and the descriptions are whimsical, but in a children’s book there must be a lesson. The animals start bickering about who’s right. They decide to visit A Man of Science, and each Being hopes that he will confirm their perspective.

Bullfrog knows the moon as a lily pad... and here it floats on Lake Namakagon!
Photo by Emily Stone. 

I was enjoying the story immensely up to that point, and even related to the idea that everyone wants science to support their favorite theory. Then the Man of Science spoke from his high tower. He declared that the Moon was nothing more than cold, dusty, crusty sand, plus a slew of facts and figures. As you can imagine, the animals weren’t happy with that answer. But, united against the scientist’s perspective, they went home with a greater appreciation of the many ways their group of friends knows the Moon.

The moon comes in many shapes and sizes! Photo by Emily Stone.

I felt ashamed. I think of myself as a very science-minded person, and I sensed that the author was trying to make some point about how the facts and figures of science are out to squash wonder in the world. How horrible that would be!

But as I thought about the depiction of the stuffy old man in a tower spouting information from books and declaring “To be sure, the moon is that and nothing more,” I realized that the author had constructed a strawman argument by setting up a simplistic imagined opponent that’s easy to knock down.

In real life, I don’t know any scientists who even remotely resemble the Man of Science in this story. The scientists I know are full of wonder and excitement about whatever it is they study, and pretty much everything else as well. As scientists, they are open to new information that might change their current understandings, and are well aware that we don’t know even a fraction of everything there is to know.

For example, the Man of Science declares that the Moon is made of sand, as if that’s boring. But sand here on Earth is fascinating! In one of my early geology classes, Professor Tom Fitz jumped on a desk because he was so excited by a rock. Each sand-sized clast in the stone was perfectly polished quartz with a billion years of history. They had paused their journey in an environment of deposition so unique that each clast was almost exactly the same size as every other one. Later that year I walked on a beach—the tombolo at Stockton Island in the Apostle Islands—made from similar sand grains and they sang beneath my shoes.

The well-sorted (all the same size) sand grains on Stockton Island's tombolo squeak when you walk on them! Photo by Emily Stone. 

I wonder if the piping plover I saw on Stockton Island had squeaky footsteps, too? Photo by Emily Stone. 

When I taught kids in California, we looked closely at handfuls of sand born in the uber productive waters of the Pacific Ocean. Not only did a rainbow of minerals shine like jewels, but fragments of every type of seashell and tidepool detritus taunted us with mysterious patterns as we tried to guess their origins.

Of course, sand on the Moon is neither rounded and sorted nor full of seashells. From a Radio Lab podcast I learned that Moon sand is razor sharp! With no wind or water to bang pieces of rock against each other, there’s no mechanism to round off the corners of rock fragments created by impacts from tiny micrometeorites or impressive asteroids.

Impacts to the moon don't just create craters, they also make razor sharp sand! Photo by Emily Stone. 

As for the Moon being what that strawman knows and nothing more, scientists haven’t even agreed on exactly how the Moon was formed, and we’re continually learning about how it impacts life on Earth. Midwesterners don’t often encounter the Moon’s tug on ocean tides, but the pull of the Moon on the core of the Earth likely contributes to the maintenance of the Earth’s magnetic field, as well as shifts in the magnetic field’s strength that influences plants, snowshoe hares, lynx, and more.

Photo by Emily Stone. 

New discoveries about the Moon abound, and the scientists are excited. In my view, it’s lucky that this book by Stephen Anderson is out of print. Scientists deserve a place in our worldview right alongside those animals to look up at the Moon and think about all the possibilities it contains. Teaching kids—and everyone—to practice empathy and open-mindedness is great, but giving children an incorrect view of science and scientists isn’t going to help them navigate our changing world. It isn’t going to help them to know the Moon.

How do we know the Moon? Everyone has their own relationship with the Earth’s beautiful satellite. Photo by Emily Stone. (The Super Moon on November 16, 2016.)

Emily’s third book, Natural Connections3: A Web Endlessly Woven, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Our Winter Calendar is open for registration! Visit our new exhibit, “Becoming the Northwoods: Akiing (A Special Place). Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.


Here's a few fun links to info about the Moon: 

https://radiolab.org/podcast/the-moon-itself/transcript

https://cablemuseumnaturalconnections.blogspot.com/2021/06/whip-poor-will.html

https://cablemuseumnaturalconnections.blogspot.com/2018/09/stranger-than-we-can-imagine.html

https://www.sciencealert.com/our-moon-is-curiously-lopsided-and-a-massive-impact-could-be-to-blame

https://www.amnh.org/exhibitions/permanent/meteorites/meteorite-impacts/on-the-moon

https://science.nasa.gov/moon/tidal-locking/

https://science.nasa.gov/moon/weather-on-the-moon/

https://science.nasa.gov/moon/formation/

https://science.nasa.gov/moon/composition/

https://www.universetoday.com/articles/moons-insides-still-hot-hot-hot-after-billions-of-years-of-formation-study

Why Woodpeckers Don’t Get Concussions

Years ago, Lois Nestel, the Museum’s founding director, wrote:

“I was stalking a pileated woodpecker whose calls and rapid fire hammerings seemed to come consistently from one area of trees not far from the house. These big, wary birds are not easy to pursue, so reasonable caution was necessary.

“Silence ahead seemed to indicate that the big bird had flown, but the apprehension was dispelled as, from a pine stub ahead, there came a staccato burst and bits of flying wood. A stealthy approach, timed with the pecking, ended abruptly when a large black beak topped by bright eyes and a flame red cockade was suddenly thrust around the side of the stub. With much scuffling of feet the crow-sized black body came into view. Unaware of being watched, the big bird seemed to talk to himself with soft knocking notes as if trying to decide where to drill the next hole.

Pileated woodpeckers have been increasing in numbers as we allow trees to get big and old. Photo by Emily Stone.

“Some unwary movement or sound on my part suddenly alerted him. There was a brief eye-to-eye confrontation; then the broad wings spread and with a few swooping beats bore the great woodpecker into the safety and seclusion of the forest.

“The pine stub bore evidence of much work. Large openings had been chopped through the shell and into the honeycombed interior. Breaking open a piece of this riddled wood revealed the dormant bodies of large black ants. This was what had attracted the woodpecker and would undoubtedly bring him back again. I might not be around to see, but the sound of drumming would bring to mind a clear picture of a great black bird with a flaming topknot—a memory to treasure.”

Lois’s experience with the woodpecker in the forest is timeless. How many of us have had the thrill of seeing or hearing these large birds swoop across the road, tear apart a backyard stump, or disappear into the forest? Actually, far more of us than in Lois’s day. Unlike many birds, populations of pileated woodpeckers have been increasing since 1966 due to the regrowth of large trees and the conversion of some large trees into food-rich snags. I’m sure Lois would be thrilled!

These days, during my own frequent encounters with pileated woodpeckers, I can think about the science behind the question I asked in the first chapter of my second book: “How can that little bird bang his head against trees all day and not develop debilitating headaches?”

Some of the initial research into this question, starting in the 1970s, proposed that areas of sponge-like bones in a woodpecker’s skull act as shock absorbers to protect the brain. Subsequent research, and logic, has disproved that. Pounding with a squishy hammer means that you have to pound harder to get the work done! Instead, newer research shows that a woodpecker’s muscles engage in a way that stiffens their body and transfers energy more efficiently. This seems to include exhaling with every bill strike—just the way I grunt to stabilize my core while picking up something heavy.

This female hairy woodpecker can pound away all day and not get a concussion. Several simple adaptations make that possible. Photo by Emily Stone.

When I wrote about pileated woodpeckers in February 2022, I was excited that some scientists had celebrated the woodpecker’s tongue as a brain-protector. Woodpeckers have a long tongue that wraps around the back of their skull. A Y-shaped bone called a hyoid apparatus supports the tongue and helps it extend into tree holes and extract insects for lunch. The researchers hypothesized that it also acts like a seatbelt for the brain. This was a fun “fact” to share with people!

After a neighbor suggested recently that I write about pileated woodpeckers again, I decided to see if there was any new research. Indeed! In 2024, James M. Smoliga of Tufts University School of Medicine summarized and critiqued the research on woodpecker brain protection. He criticized the hyoid seatbelt hypothesis for making conclusions based on preserved tissues with altered characteristics and the biomechanical properties of a human tendon. I will have to stop telling people that a woodpecker’s tongue cushions their brain.

Downy woodpecker with a sharp, stiff beak.  Photo by Emily Stone.

Smoliga concluded that, as far as current research shows, woodpeckers survive banging their heads against trees because they have less fluid in their brains than we do, which limits the “sloshing” of their brains within their skulls. And, in contrast to the impacts that cause concussions in humans or concussion-like symptoms in birds who have hit windows, woodpecker’s strikes are short, intentional, and involve coordinated muscle movement from back to front in a linear vs rotational way. The newest calculations, made with the most accurate modern technology, predict that a woodpecker would have to strike a tree twice as hard as usual to give themself a concussion.

Of course, any of these conclusions might be proven wrong or incomplete as scientists discover new information in the future. The beauty of science is that it requires us to be able to change our minds in light of new evidence. One thing that doesn’t need to change is the magic we feel, as Lois did, when we watch a great black bird with a flaming topknot spread their broad wings and with a few swooping beats disappear into the forest.

Emily’s brand-new third book, Natural Connections3: A Web Endlessly Woven, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Our Winter Calendar is open for registration! Visit our new exhibit, “Becoming the Northwoods: Akiing (A Special Place). Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.

Cute Bits of Camouflage

The wide brown trunk of an ash tree in front of my house makes a good backdrop for assessing the density of falling snowflakes, their potential impact on the ski trails, and the unique beauty of a particular storm. While gazing at it last week, a bit of the bark began to move. The optical illusion lasted only a second before I recognized the small oval of brown-and-white patterning as a bird.

Brown creepers are cute little bits of camouflage with white bellies. This one moved upward in staccato motions, a bit to the side, around to the back, back to the front, and up some more. Pausing, the bird used their thin, downward-curving bill to explore a bark furrow. Perhaps they had spotted an overwintering insect larvae or antifreeze-protected spider for their lunch. Near the limit of my view out the window, the creeper suddenly launched off the tree and fluttered downward toward another tree trunk, out of sight.

Chickadees taking turns grabbing sunflower seeds at my feeder distracted me for a second, until movement at the base of the same tree again caught my eye. The brown creeper (or their mate?) was spiraling upward again. Apparently, there are enough crevices in a big tree like this that it pays to make many trips around the trunk.

Can you see the long claws and curved beak on this brown creeper? Photo by Emily Stone. 

The creeper hopped with both feet at once, and I knew that their curved claws were gripping tight. Their long, stiff tail braced against the bark. Just above a knothole, the creeper paused again and probed excitedly in a crevice until a flurry of motion brought a red-breasted nuthatch to that spot and the creeper flew off. The nuthatch circled, probing in the bark with their long, straight beak. Thief!

Having cleaned out that crevice, the nuthatch continued foraging downward on the trunk. Nuthatches are also known for their agility in navigating tree trunks, but whereas creepers go up, nuthatches specialize in going down. They are assisted by one backward pointing toe with a long claw on each foot. Nuthatches can hop in every direction, though, and even dangle on the twig tips with acrobatic chickadees. Their very short tail stays out of the way.

Nuthatches are known for climbing head-down, but are pretty versatile. Photo by Emily Stone. 

The first lesson in my first ornithology class back in college used these two birds as an example of how to identify a species by their behavior. Brown creepers hop up a tree, then fly down to the next one. Nuthatches walk down and then fly back up.

Classic nuthatch behavior! Photo by Emily Stone. 

Although both nuthatch and creeper populations are thought to be stable, I see and hear many more nuthatches while I’m out in the woods. This is partly due to their brighter colors and louder calls. Nuthatches shout their distinctive yank! yank! yank! pretty consistently as they feed in mixed flocks with chickadees and woodpeckers. Brown creepers, on the other hand, have thin, high voices that are easily lost among the contact calls of other birds. I’m not the only one who tunes out their songs. A study published in The Canadian Field-Naturalist journal in 2020, discovered that brown creepers do sing in the dawn chorus, but it took an automated recording to notice them consistently.

It's not just that nuthatches are easier to see and hear. They are also far more numerous. There are almost three times as many red- and white-breasted nuthatches in the world as brown creepers! Perhaps this is because brown creepers have some unique habitat requirements.

Brown creepers need forests with large trees for both foraging and nesting. They build their nests behind pieces of loose bark, which are more common on large trees that are dead or dying. Big trees also have deeper furrows for hiding the tasty insects and spiders that creepers prefer. Creepers occasionally eat seeds or suet, but rarely visit feeders. One study found that the gnarly bark of large yellow birch trees make good habitat in the East, while they are found in conifer forests in the West. These populations of creepers may actually be different subspecies, but physically they blend in with each other as much as they do the trees. It’s only through DNA studies that scientists are learning to separate them.

Nuthatches seem to thrive in a wider range of habitats and ages of forests. Nuthatches reuse old woodpecker cavities for nests, and sometimes excavate a hole themselves, but these can be in smallish trees. Both red-breasted and white-breasted nuthatches are much more likely to eat seeds than creepers, which expands their options to include bird feeders.

Happily, the greedy nuthatch didn’t scare away the brown creeper for long. As the snowflakes drifted down, the cute little bit of camouflage returned to the tree for another expedition up, lifting my spirits as they went.

Emily’s brand-new third book, Natural Connections3: A Web Endlessly Woven, is available to purchase at www.cablemuseum.org/books and at your local independent bookstore, too.

For more than 50 years, the Cable Natural History Museum has served to connect you to the Northwoods. Our Winter Calendar is open for registration! Visit our new exhibit, “Becoming the Northwoods: Akiing (A Special Place). Follow us on Facebook, Instagram, YouTube, and cablemuseum.org to see what we are up to.