I had the opportunity to write about a fascinating topic: nautical archaeology of 19th-century steamboats.
Let’s start with archaeology. Archaeology is the study of the material remains and other evidence of humans and their ancestors. Much of this involves studying artifacts. Things like projectile points (most of which are not actually arrowheads, by the way), ceramics, clothing, baskets, beads, nails, bricks, glass, and butchered or transported bones. On a very basic level, archaeologists perform excavations, find artifacts and study them, but there’s a lot more to it than that. Archaeologists are very careful in their excavations. They don’t just dig up and collect artifacts – they record many details about the site as they excavate. For example, archaeologists keep notes about things like the color and texture of the soils in which artifacts are found (and the ones where no artifacts appear, which is also important to know). Each artifact retains a label that tells researchers which soil level it came from, what part of the site it was found in, whether it was found in a feature (we’ll get to that), and other important information that would otherwise be lost once the artifacts are out of the ground. And there are lots of important parts of a site that aren’t artifacts. For example, features. Features are physically IN the soil – things like graves, building foundations, hearths and outhouse pits. These, too, are part of the context.
Finally, it’s not just about finding artifacts. It’s about placing these artifacts in a larger context. It’s about what was found with what. Does this piece of pottery match up with that one from a different area of the site? These pottery pieces (and the other artifacts that were found in the same layer with them) were probably deposited at the same time. Is this shell pendant from a dark, stained soil that lines up with a bunch of other dark stains? Likely it was dropped when someone was digging postholes for the the wall whose logs have long since rotted out, leaving a line of stains in the soil. Someone used to live here. Someone built a wall. Someone’s necklace fell off. (And about that shell. Is it local? Or is it from an animal that lives a few hundred miles away? Hello, trade network.) In other words, archaeology is like trying to put together a puzzle — all the pieces need to come together, and it’s their relationship to each other that reveals the real picture of what was happening at a site.
Now, paleontology. It’s a pretty broad term. Many people hear paleontology and instantly think dinosaurs. That’s accurate, just not comprehensive. Paleontologists also study: clams leaves pollen mammals non-dinosaur reptiles amphibians birds oysters plankton insects bones shells footprints worm burrows the sediments around all these thingsYou get the idea.
Paleontology is the study of animals or plants or other living things that have died and (hopefully) been preserved in some way. And there are lots of different ways for something to get preserved (that’s a blog post in itself and – hmmm- yeah, I’ll write that one too). Sometimes bones or shells or leaves – in other words, the remains of living things – are what actually gets fossilized. Sometimes, just an imprint or a cast of them does. But sometimes, a moment or a behavior gets preserved instead. Footprints are an example of this. So are burrows on the ocean floor, created by marine invertebrates. You can see them in the preserved sediments of these environments. In fact, the study of these types of fossils has a name: ichnology.
Paleontologists carry trusty field notebooks and pens and labels, just like archaeologists do, and for the same reason. It’s important to document what was found where, and with what. Paleontologists keep notes about the type of sediment or rock where fossils were found. They write down the rock formation, the location, and possible interpretations of the sedimentary context (there’s that word again).
It turns out that paleontology and archaeology share several interesting similarities and even overlap. For one thing, when things get old enough (from the perspective of modern humans and their ancestors and extinct relatives), sometimes it’s hard to know who’s an archaeologist and who’s a paleontologist. Excavating and studying the remains of fossil hominins can be fairly described as a paleontological pursuit (just as studying their tools is an archaeological pursuit) – especially if the research partially includes studying the fossils of animals from the surrounding area (which helps scientists to reconstruct the environment in which hominids lived). Other ancient creatures and organisms also help to inform archaeological questions. For example, there are archaeologists who study pollen in order to place the sites they study in environmental context, and to understand how humans may have impacted their environment.
And there are similarities in the actual pursuits themselves. Both are looking for evidence of the past in sediments or rock – the image of the excavator holding a trowel, a pickaxe, a rock hammer, a shovel, is so iconic that I’m guessing it’s part of the reason anyone mixes these fields up in the first place. But importantly, both archaeologists and paleontologists often end up with… nothing. Just because you dug a hole somewhere doesn’t mean there’ll be artifacts it. Just because you walk an outcrop doesn’t mean there’ll be fossils eroding out just there. Finding nothing is something all excavators have to get used to and accept as part of the job. A day in the field is still a day in the field, though, and there’s not an archaeologist or a paleontologist I know who would call that nothing.And finally, in both archaeology and paleontology, context is everything. Check out these two sentences:
The bone fragments, along with shards of ceramic of a style dated to about 6,000 years ago, were located in the same soil stratum and within a concentration of fire-cracked rock.
The bone was found among Pleistocene gravels and rocks representing a lag deposit.
The sentences have a couple of things in common. A few things are different, too. In one case we’re clearly talking about bone and rock that are from an archaeological site, and it’s substantially younger than the other site, which also has bone and rock but seems to be paleontological, not archaeological, in origin. In other words, their context is what tells us how to interpret them.
If you’re like me, then just the words “bone” and “rock” are at least a little exciting. But the fact is, there’s not much to go on without the complete sentences. This is why archaeologists and paleontologists constantly look at things in context. And it’s why excavating carefully and documenting the context is so important.
Context always matters. It’s how these pieces of the past go from isolated syllables to telling their – our – story, decades or millenia after they found their way into the record. It’s how we pull together a shard of this and fragment of that, and put together the story of life on earth, with our little piece of it, falling into place.
Here’s an example of a way that we can consider and care for wildlife by providing corridors.
See below for my original (brief) post on this topic:
In ecological terms, a corridor is a pathway of natural habitat between two larger patches of habitat. Animals can use corridors to travel from one living space to another. As more and more space is developed, we are sacrificing these ecologically crucial pathways. Here’s one reason that corridors matter.
My new story in EARTH magazine: a new look at the Ice Free Corridor, with implications for how and when humans first entered the Americas!