Sunday, January 22, 2017

Hunting Fossils - Part 3

By the end of the day, I’m whipped. Sweating, dusty, gritty, I take my haul back to the office. I have plastic bags marked with slips of paper as N14V-1, N14V-2, and so on. These markings are unique in this year, and they correspond to entries Marcie has made in the log book. The codes connect to her written description and to photos taken of the site. Or, in my case, a single photo, as the hillock I worked on yielded nothing spectacular.

Today, nothing spectacular was found by any of us. For the whole month, the best find was a single entelodont tooth in perfect condition, probably an m1, or lower molar. The woman in the group with the smallest hand could not close her hand around it--it’s that big. Had we found a canine--the fang--it would have been longer than the largest hand of the group. And we looked for it. (image-google “entelodont tooth” to see some, as there are no images in the public domain I can use here)

When the grad student found the entelodont tooth, another joined her to search the area all around it. But it was a lone tooth, probably washed from the full skeleton by water. As entelodonts were alpha predators, the teeth and bones wouldn’t have had the typical distribution of prey animal fossils.

There is such a thing, though I don’t know if there’s a mathematical description of the dispersal of bones. Because we were hunting fossils in a rural area, there were plenty of chances for the paleontologists to keep track of local predator kills. If a fox killed a rat, the kill was left alone, and a scientist would go out twice a week and check out the way the bones were being pulled away by scavengers. He might pick one up briefly to study tooth marks in the bone, but he’d carefully replace it where it had been. In two months, he’d have a movie running in his head of the way the bones dispersed, were trodden, moved away from one another. And that knowledge, he’d apply to hunting for fossil bones.

A.Weith, Wikipedia. Predators disperse bones

Some fossil bones are dispersed like that. Some are not. One of the easier ways to find them is when they’ve been dragged into a den of a dog or weasel or extinct burrowing creodont. Then you might find a whole bundle of them together. But watch out! You might be looking at the bones of four different kills, so it takes care to identify them all correctly.

Local hunters know that the scientists here are always on the lookout for recent kills. Sometimes, they also bring in a dead animal, and the lead paleontologist takes it home, boils it up (outside on the grill, his wife emphasized during a party she hosted) and turns it into only bones. The bones are set out, dried, and labeled. We use these to examine the processes and notches and foramina -- bumps and holes on bones -- to compare to fossil bones we find. Is this single fossil bone, unattached to anything else, an tarsal or a coccyx or something else? Modern anatomy comparisons can help identify this and give a basis for comparison of animal size. A cabinet in the museum is dedicated to modern bones used for this purpose. Bobcats, martens, beavers, a dog killed on the road, and more each have their separate box, filled with smaller boxes of bone groups, each carefully labeled.

“Carefully label” might as well be the job description here. I’ve learned some of the work of a curator of a fossil collection during my time here, too, and the working in a computer system used throughout the federal government for natural history collections. I’ve done spot checks on inventory. Pulled out specimens for visiting scientists to study. Pulled out rare specimens to be cast and sent to other museums and universities, either for study or display. Some sharing of actual specimens takes place, but if they are needed, they are quite rare, and instead of parcel service mailing, sometimes a skull is driven, in a carefully padded box, eight hundred miles, under the watchful eye of a professional, before it is handed over to another trusted professional. When she’s done with it, she has to drive it back. Parties are de rigueur on both ends of that trip. (Paleontologists party. A lot.)

Fossil collection drawer, much like the ones I worked with

“What are all these fossils worth?” some people ask. The truth is, I don’t know. Serious scientists don’t value fossils in dollars, and they don’t buy them, and they frown on any museum that does. That encourages pilfering and, as I mentioned a couple of posts ago, amateurs stealing fossils out of the ground means that nothing can be learned from them. Sure, the kiddies at the Field Museum might be impressed by the display...but it’s irresponsible of the museum to pay cash and drive an illegal trade in fossils. And quite frankly, the kiddies would have been equally impressed with a plaster replica as with a true fossil skeleton. I’ve caught the disdain of the scientists here for the few big natural history museums that engage in cash exchanges for fossil bones. And don’t ask them what they think of fossils sold on E-bay, not unless you want a ranting earful.

Knowledge is priceless. To the scientists I have met, putting a dollar value on a fossil is like putting a dollar value on a kid’s love for his grandma. Impossible to quantify.

When I have made sure the paperwork is all in order, I leave as quickly as I can to get into a shower. I’ve never taken showers this cold before, but my body is so overheated by the end of the afternoon in the searing canyon, I need it. I shower until I shiver. Then I rehydrate.

Tomorrow I’ll come back and work on the second part of the process, making a fossil found two years ago come fully out of the rock it was in.

(series will finish next week)

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