An 5,500-Year-Old Forest in Yellowstone Melted Out of the Ice
Let’s start 2025 off strong by avoiding it entirely and escaping a thousand years into the past to an Amazonian civilization of forest islands, garden cities, and duck tales. From there, we’ll flee even farther from the present, though we’ll keep the “enchanted forest” vibe going strong.
Then, the BATS are SURFING. What else do you want to know? Close up shop; we’ve reached the pinnacle of enlightenment. And finally, want to see some robots hula hoop? You came to the right place.
Happy New Year to all who acknowledge the passage of time, and congratulations to anyone who has managed to transcend it.
The Ancient Garden Cities of Llanos de Mojos
It’s unwise to romanticize any past society or culture. Humans are reliably humans, with all that this entails, across time and continents. But when you encounter tales of garden cities linked by vast causeways and populated by people and their pet ducks, it can be a little hard not to indulge in daydreams about life there.
That’s the scene unveiled in a new study on the Casarabe culture, who lived in the Llanos de Mojos region of the Bolivian Amazon between 500 and 1400, before the arrival of Europeans. Over the centuries, these people built roughly 200 monumental mounds linked by more than 600 miles of canals and causeways. The sprawl included primary urban centers and small forest islands, which are cultivated patches of trees amid the wetland plains.
“The sheer volume of sites and their architectural layout, divided into a four-tier settlement system…indicate that the people of the Casarabe culture created a new social and public landscape through monumentality, leading to low-density urbanism,” said researchers led by Tiago Hermengildo of the Max Planck Institute of Geoanthropology. “The extent and complexity of the Casarabe settlement network present a unique context in the South American lowlands.”
To better understand the diets and lifestyles of these people, Hermengildo and his colleagues collected isotope data from the remains of 86 humans and 68 animals (including mammals, reptiles, birds, and fish) that lived in Llanos de Mojos between 700 and 1400. The results revealed that maize was the central staple of the Casarabe diet—both for its people, and its ducks.
“We provide evidence that muscovy ducks (Cairina moschata), the only known domesticated vertebrate in the South American lowlands, had substantial maize intake suggesting intentional feeding, or even their domestication, from as early as 800 CE,” said the team. “Similar isotopic evidence indicative of maize feeding practices was also reported in muscovy duck from Panama, suggesting that maize was a key element in the domestication of ducks throughout the American continent.”
Feeding ducks: a meditative passtime for the ages. Though the birds were raised for sustenance, I like to imagine a few charismatic drakes and hens earned a role as companions.
But regardless of the charm quotients of bygone ducks, these findings are part of a wave of emerging research revealing that ancient cultures in the Amazon Basin were far more complex and extensive than previously realized—and researchers have only started to scratch the surface of many of these sites. Get your brain checked now, because this field is going to be throwing out head-spinners and mind-bogglers for years to come.
Yellowstone’s Lost Woods
As global temperatures rise, alpine snowpack and glaciers are receding, a pattern that often exposes fossils, artifacts, and other relics that have been locked in ice for millennia.
For instance, scientists recently discovered an eerily well-preserved forest of whitepark pines that melted out of an ice patch on Yellowstone’s Beartooth Plateau. This forest stand thrived about 5,500 years ago, but the ice left it in such pristine condition that scientists were able to measure tree rings and reconstruct the climate these trees experienced over five centuries.
“The extraordinary quality of wood preservation at the…ice-patch site provides an opportunity to generate a multicentury, mid-Holocene record of high-elevation temperature during the life of the forest stand, and to elucidate the climate conditions that contributed to the stand’s demise and subsequent growth of the ice patch,” said researchers led by Gregory Pederson of the U.S. Geological Survey.
The treeline in the Beartooth Mountains was at a much higher elevation 5,500 years ago due to a multi-century warm spell. Then, around 5,100 years ago, Iceland went on an epic volcanic bender, as it is prone to do from time to time, causing a “summer cooling anomaly” that “led to rapid ice-patch growth and preservation of the trees,” according to the study.
In other words, Iceland’s stinky lava breath likely killed off this forest all the way in Wyoming by cooling the Northern Hemisphere, which entombed the stand in ice.
The study notes that the treeline is likely to creep back up the slopes again as anthropogenic climate change melts ice off at high elevations. Pines may grow once more on the ancestral grounds of this ancient forest, as a consequence of human activity.
BATS SURF
Hurme, Edward et al. “Bats surf storm fronts during spring migration.” Science.
Bats surf.
Let that sentence breathe. Just two words, yet it may well be the shortcut to nirvana. Dust to dust. Hallelujah. BATS SURF.
In addition to being my new incantation for 2025, “bats surf” is a scientific discovery reported this week. Researchers outfitted 71 female common noctule bats (Nyctalus noctule) with tags and followed their spring migration across Europe, which lasted about 46 days and covered nearly 700 miles. Some of these batgirls covered an astonishing 237 miles in just a single night, much farther than previously recorded flights.
The noctules were able to achieve these distances by timing their flights to coincide with warm fronts that buoyed them along with strong winds. In other words, bats surf the tropospheric waves. This skill is especially important for female noctules, as they must navigate migrations at the same time they are gestating future surfer pups in their bellies.
“Females are generally pregnant in spring and can delay the embryo’s development through torpor,” said researchers led by Edward Hurme of the Max Planck Institute of Animal Behavior.
“As these bats wait for the right migration conditions, they must either invest in their embryo while increasing their own energetic cost of flight or delay the development of the embryo, possibly affecting the pup’s survival,” the team said. “This phenological flexibility may be key for their long-term survival and maintenance of migration.”
Parenthood is hard enough without having to worry getting literally weighed down by your brood on the road. There’s no hanging loose for these bats; they are truly on a journey of surf-ival.
Robots Taking Hula Hoop Jobs
You might be a scientist if you look at a hula hoop and think “this familiar playtime activity can serve as an archetype of the challenging class of problems involving parametric excitation by driven supports and the mechanics of dynamic contact points with frictional and normal forces.”
That’s a quote from a new study that investigated the complex dynamics behind “hula hoop levitation,” which describes how skilled hoopers synchronize their body movements in ways that appear to defy gravity. The study belongs to one of my favorite research traditions—the earnest examination of an outwardly trivial item, a class that also includes the nano-pasta work we recently covered and a legendary 2022 breakdown of the fluid dynamics of Oreos.
“Seemingly simple toys and games often involve surprisingly subtle physics and mathematics,” said researchers led by Xintong Zhu of New York University. “The physics of hula hooping was first studied as an excitation phenomenon soon after the toy became a fad, and more recent interest has come during its renewed popularity as a form of exercise and performance art.”
In addition to outlining the physical underpinnings of levitation, the authors took the inspired step of experimenting with a variety of hula-hooping robots. The study is punctuated by frankly delightful footage of these machines hooping their cold metal hearts out. See for yourself; the study will be open-access for six months.
The upshot: We now have experimental confirmation that people (or robots) with “sufficiently curvy” figures have a hooping advantage. The team notes that “an hourglass-shaped body of hyperboloidal form successfully suspends the hoop.”
Shout out to all you hyperboloids out there! Happy hooping.
Thanks for reading! See you next week.
