Tips on How to Become a Fossil

Earlier this summer, on a break from scraping Jurassic stone off dinosaur bones at an eastern Utah quarry, I wandered through the fantastical landscape of Arches National Park. While following the short Park Avenue trail, I noticed that the burnt orange sand running down the middle of the canyon retained the footprints of previous visitors.

Looking at the footprints, thinking about how long they might last, a peculiar question struck me: When I die, will I leave any traces behind in the fossil record?

Fossils are not just bones. A fossil can be part of an organism's actual form, of course, such as a skeleton or carbonized plant remains. But fossils can also be evidence that an organism passed that way long ago, like footprints or idle twirls left by a twig floating along a river bottom. Or like the "Blue Lake rhino," a 15-million-year-old mold of a two-horned rhino that was created when lava poured into a lake, surrounded the herbivore's body, and then cooled.

For most species, becoming a fossil is an accident. Those footprints along the Park Avenue trail, with my sandal impressions among them, could become preserved in a petrified slab for some paleontologist of the future to mull over. But for that to happen, the tracks would have to keep their form - perhaps given a little support by some morning moisture - while new sediment totally covered them. That's how early Jurassic dinosaur footprints found just outside Arches might have formed, back when Utah was covered by huge sand dunes.

Could footprints be future fossils? The rock of Arches preserves the steps of much older organisms.

Photograph from Travel Ink/Gallo Images/Getty Images

Given the choice, I'd prefer to leave a body fossil. Sure, my tracks across a patch of desert would record my behavior through the soles of my footwear, but I particularly relish the idea of leaving a skeleton - or at least parts of one - behind.

Bury Your Coffin-Free Body in Sediment

I can enhance my chances of winding up as a skeletal remnant of my present self by employing taphonomy—the study of the long-term postmortem history of organisms—in reverse.

Taphonomy tells me two things. First, I'll have to go without a coffin. The sooner I can be buried by sediment and kept safe from the various organisms that decay a body after death, the better.

More important, though, I'll have to carefully select where I wind up. Fossils en potentia have to be buried, which means that I'd need to find a place undergoing active deposition. That's why the vast majority of fossils are found in sedimentary rock —vestiges of lakes, rivers, seas, and dune-pocked deserts. We know virtually nothing of animals that lived on mountains or other habitats that undergo erosion.

Rapid burial also helps stave off the destructive actions of scavengers. I suppose scraps of my flesh and bone could end up in the feces of a scavenger and still count as part of the fossil record, but I'd prefer to stay relatively intact.

Scavengers aren't the only destructive agents to worry about. A body must endure an entire gauntlet of ecological recyclers—bacteria, fungi, burrowing insects, plant roots—before it even has a hope of becoming a fossil. So while I'd be tempted to have myself interred on a floodplain where my remains would be buried under tons of fine-grained sediment—much like the dinosaur-era sites I've been working on this summer—there's no guarantee that the natural cleanup crew wouldn't put my bodily resources to their own uses.

Die in the Desert or Near a Volcano

Not every sedimentary scene is equal. Different kinds of sediment, as well as other aspects of the environment, will affect the long-term history of my bones. If I choose a sandy river channel, my skeleton might be tumbled to different resting places, leaving behind a perplexing smattering of isolated bones and scraps.

A desert burial has some perks: My drying corpse might become home to beetles and other insects that burrow in bones, their circuitous pathways permanently recorded in my skeleton. Burial in the deep sea might yield a similar outcome. After sharks and crabs had their fill, my bones might become home for bone-eating snot-flower worms that rely on the skeletons of whales and other benthic bonanzas to carry out their peculiar life cycles. These strange organisms create fossils within fossils.

If I want my bones to stay together, and possibly have tatters of my hair and soft tissues preserved, burial in fresh volcanic ash might work. These sorts of deposits have yielded scores of feathered dinosaurs and Mesozoic mammals with halos of fur around them. (Although I'm disappointed that even fresh volcanic ash probably wouldn't preserve my "Future Transitional Fossil" T-shirt, which I will wear to my grave anyway in hope of making a future paleontologist smirk.)

Or Maybe in Muck

After carefully weighing all the options, I think I'd prefer to follow the example of Archaeopteryx and sink into oxygen-depleted muck. The early bird's remains settled at the bottom of an ancient lagoon over 150 million years ago, when Europe was an archipelago and the ocean floor's anoxic conditions were so hostile that even bacteria avoided it. Beautifully preserved bodies of crustaceans, fish, leathery-winged pterosaurs, and Archaeopteryx came down through the eons as some of the most gorgeous natural art ever seen.

Archaeopteryx knew how to go out in style. Particulars of where the early bird died preserved the fossil in high definition.

Photograph by James L. Amos, National Geographic

But even a perfect burial doesn't guarantee discovery. In the millions of years of Earth history that lie ahead, oceans and mountains will rise and fall, and the continents will shift. Should my remains actually become a part of the fossil record, they may rest in a place wholly inaccessible to any future explorers. Even if I come to my final rest at an accessible spot on the surface, erosion might expose and destroy what's left of me. Or there may not be any future explorers to find me. This is why the discovery of any fossil is a joyous occasion. In the face of so much destructive potential, a fragment of the past has survived and at long last been found.

Follow Brian Switek on Twitter. Read his Laelaps blog on National Geographic's Phenomena.