As I write, the Snowmass Water and Sanitation Department District is busy digging, damming, and filling the Ziegler Reservoir on top of one of the world's only known high-altitude Ice Age fossil sites -- and "without question" the world's finest mastodon site, according to Denver Museum of Nature and Science VP Kirk Johnson -- near Snowmass Village, CO, a ski resort.
Fortunately for us, the DMNS had 70 days spread over two seasons to get in, dig like hell, and get out. In the process, they managed to collect some 5,000 large bones of elephant-like mammoths and masotodons, and ice-age deer, sloths, camels, giant bison, horses, and, of course, beavers, and perhaps 10,000 more microfossils (salamander bones, beetle carapaces, pressed plant parts, etc.) while somehow managing to not freeze their arsses off (or at least not complain about it publicly) in the cold mud and thin air at over 8,000 feet during 10-hour days. I doff my hat to them.
Last fall I took a tour of their autumn finds and did a little photo tour here. For still more on this story (I will omit most of the background from this post since I want to focus on the finds themselves), see the fine New York Times article of July 4 here, or this piece from (of all places) the Aspen Business Journal. A few weeks ago, the museum held another one-day public display of finds from Snowmastodon Dig Round II ( they stopped for winter, and the spring dig wrapped up at the beginning of July) to show off about 30 bones of their 5,000. Both out of curiosity, and because I'm the only Scientific American blogger in Colorado, I took another trip down to see them**.
For your viewing entertainment, I present another short tour of the finds. I apologize in advance for the quality of the photos. In addition to owning a cheap, hand-me-down camera, the bones were displayed on black cloth with white labels in a dim room. Not the best composition for a cheap photosensor, as I'm sure Alex Wild could explain in detail. I'm saving up for that $500 Canon PowerShot S95, I promise.
Here we have the bones laid out as they were that day. In the one-day public display, there were three long tables of this size. In front you see a mastodon acetabulum, the "little vinegar cup" that is the socket of the hip ball-and-socket joint. Think about how big the one was on the human skeleton in high school biology. This is the joint that goes out frequently on old folks and has to be replaced with a bionic ball or socket. In the mid-ground is a mastodon tooth and tusk fragment, and in the background are various leg bones . . .
. . . like this mastodon tibia and assorted carpals and phalanges. Carpals and phalanges are, as you will recall, secret bio-nerd code names for finger and toe bones.
Here we have a genuine bio-nerd in the flesh, my dear friend Nathan, proprietor of the fine bird vocalization blog earbirding.com. He is demonstrating the difference between an H. sapiens femur (upper leg bone) and a juvenile mastodon femur. Juvenile, folks. Juvenile.
So, if you ever wondered how big a mastodon vertebra is, here is your answer. In the foreground are two mastodon (guessing here) thoracic and/or lumbar vertebrae. Answer: BIG.
And here is a mastodon sacrum (the bit right before the coccyx, or tail bone, in humans, and a cervical vertebra (C3), one of the first few just below the skull in the background.
Now we move to the sloth section of our program. The discovery of giant ground sloth bits at Snowmastodon was probably one of the most surprising finds of the dig. No one suspected they lived at high altitude. On the left, an admittedly warped-looking (to my eyes) tibia, and at right, one of their claws. Said claws were deployed thusly:
As you'll recall, today's sloths are known for moving so slowly and insouciantly that they grow algae in their fur as camoflauge. So these giant ground sloths are a bit of a departure from our typical sloth image. Perhaps sloth is not the best name for this particular flavor. Perhaps "slash" would be better. I have been informed that the business-in-the-front, business-in-the-back spines of the North America's honey locust trees evolved for defense against giant ground sloths, and have stuck around(!) even after sloth extinction, until intrepid plant scientists gave us yard-friendly spine-free forms. In similar fashion, North American pronghorn, the fastest mammal in the Western hemisphere, may have evolved to outrun extinct American cheetahs. The cheetahs are gone, but the pronghorn still run fast.
Which brings us to the bison. Note the fragment of horn and skull in this photo. Note also the baby mastodon ulna. I'll pause here while you collectively think, "BABY mastodon ulna!!! AWWWWWW!"
The giant bison skull and horn (of the species Bison latifrons) are notable for their size. Like seemingly everything else from the Ice Age, they were on a larger unit scale than mosts beasts of our time. The horn in the photo above is probably at least a foot long, and it's broken or worn. For comparison, here's Bison antiquus, another extinct bison that is still slightly larger than the bison we have today. Note that its horns are only about 5 inches long.
Contemplate the scale of the giant Bison latifrons. According to the Wikitron, this translated into a height of 2.5 meters (8.5 feet) at the shoulders, and a horn-span of over 2 meters (6.5 feet). DAMN. Here's a photo of a complete rack from the American Museum of Natural History, already suitable for mounting on the grill of your nearest Texas Cadillac or Wyoming half-ton pickup.
Here we have a crappy photo of the only plant entry in the field that day, but it is an interesting one. It appears to be a wood burl, or a section of tree where a plant parasite of some sort -- virus, bacterium, or fungus -- got in and secreted a plant growth hormone mimic. Essentially, it was demanding food. In response, the tree grew quickly but deformedly around the invader, feeding it and warping the wood. This sort of thing happens all the time today (just look in your nearest forest for tree warts or tumors), but it is really cool to find evidence of it happening tens of thousands of years ago. It's all covered in plastic wrap to prevent the wood from flaking apart.
I had to take a picture of Snowy, the dig's mastodon mascot, operated and performed by paleopuppeteer Mr. Bones, who has also designed and built his own moveable, wearable T. rex. Kids could not wait to walk up and touch Snowy, and were mesmerized by the lifelike movements. I did a google search for this guy in order to give him credit and publicize his awesomeness, but I could not find him. Who IS that be-mastodoned man?? I don't know who you are, Mr. Bones, but I take my hat off to your paleontology-performance art fusion, construction skills, and nerd-tastic attention to detail. This even extended to proper licensing . . .
That's a Colorado "Snowy" personal plate, but it wasn't stamped by the state. He hand-made and painted it himself. The street cred is really off the scale here.
Here we have a comparison of the teeth of elephant (left), mammoth (middle), and mastodon (right). As you can see, elephants and mammoths are closely related, but masodons and mammoths are not. Elephants and mammoths were grazers (grass-eaters), while mastodons were browsers (broadleaf eaters). You can also see why mastodon means breast-tooth, and how the Tetons got their name. I still think mammoth and elephant teeth look like some sort of fossil coral -- or scrub brushes. I guess they kinda operated that way too. And yes, those are plush toothbrushes and dental picks so the wee ones could practice proper mammoth dental care . . .
Now here is something I had definitely not seen before . . .
In the background we have a photo of the Snowmastodon site as a whole. Note the excavation equipment and trucks at bottom. Note the ski slopes DIRECTLY ABOVE. I knew it was near the slopes, but not *that* near. Let it never be said that world isn't still full of wonderful surprises in unexpected places . . .
Finally, we have this bad boy. It was lurking in the lobby near the cafeteria. I hadn't noticed it until I was on my way out.
Obviously, it's a fossil prepared in age-old paleontolgical fashion by entombment in plaster. Here's a closeup:
As you can see it is a Fossil plaster jacket containing CLAY MAMMOTH Fossil, it is from Ziegler Rervoir, near Snowmass Village, CO (near Aspen, CO), and was prepared on or near June 19 of this year. Several of the diggers or preparators took guesses as to its weight; someone named Ian Miller guessed 9,231 #. Someone named George Sparks guessed 9,450 lb. on July 2, just above the H in mammoth. They were close. As you can see, the final weight was 10,000 lbs -- five tons. Give or take, I'm sure.
We debated amongst ourselves whether this baby was airlifted by helicopter or driven out by truck, since under his guess, George wrote "Fly home!". Yet a semi seemed a much more practical choice.As the Car Talk boys say, if you think YOU know, write it on the back of a Canon PowerShot S95 Digital Compact Camera with 10.0 Megapixel sensor with the DIGIC 4 Image Processor, f/2.0 Wide-Angle Lens, professional-style control ring, 3.8x Optical Zoom with Optical Image Stabilizer, and a 28mm Wide-Angle Lens, and mail it to Jennifer Frazer, c/o Scientific American Magazine, New York, NY, USA. You'll be glad you did.
*As a not uncoincedent reminder, yes, I AM available for freelance science writing work. : )
**plus woolly mammoths, mastodons, and giant sloths fall well within the purview of this blog, which is about the diversity of all life. And how can you not love a 13-foot tall Snuffleuppagus? Unless, I suppose, you were on the business end of a charging one.