Friday, October 18, 2013

Eggs, Turtles, and Toast: When Pareidolia Meets Paleontology

Discoverer: "Hi, Unicorn Scientist. I have made a cool discovery. At least I think I'm on to something. Can you take a look and tell me what it is?"

Unicorn Scientist: "Sure! We like seeing new things, and like people coming in with possible finds. Let's take a look."

Discoverer: "Now, I don't want to influence your opinion, but I think it is a saddle that Bigfoot uses to ride unicorns."

There is at least a minute of respectful study of the piece of shoe leather.

Unicorn Scientist: "Well, I can see why it looks like a piece of Bigfoot unicorn saddle, but saddles for unicorns are all made out of taffeta, and are stitched together with candy-floss because unicorns have such delicate skin. There are eyelet holes here for the laces of a shoe. It has the [insert your favorite shoe brand here] symbol partially preserved."

Discoverer, Version #1: "Why aren't you confirming my interpretation? It's shaped like a unicorn's back! I thought you were an expert on unicorns!"

Discoverer, Version #2: "Well OF COURSE you would say that! You've been brainwashed by Big Unicorn and are too close-minded to see the Cover-Up of the Truth!"

Discoverer, Version #3: "You have dared to disagree with my most insightful observation. I will not rest until I expose you for the fraud that you are, for the sake of all those who wish to see a Bigfoot ride a unicorn!"
* * *
Do any of these scenarios sound familiar to you? I'll bet they do. I'll bet that if you're in a profession that is remotely scientific, you've had one of these encounters.

First, I want to state that most people who bring fossils into the museum for identification do not behave like the above Discoverer. If they bring in a funky shaped rock and I tell them that it's a cool funky shaped rock, it usually spurs a series of questions which turn that funky shaped rock into a teachable moment about erosion and different rock types. Even better, if they seem really keen we can give them a behind the scenes tour and show them tonnes of real fossils, and we may even interest them in volunteer work. Of course, the pleasant encounters stick in my mind as the general warm fuzzy feeling I get when I think about the joys and passions of being in paleontology. Those fuzzy moments are thrown into sharp abrasive contrast by those other encounters.

The other encounters involve that person who, on finding a rock or an odd-shaped shadow on a photo, have already convinced themselves of the identity of the find. It's usually a fairly spectacular find (in their mind) with an even more spectacular interpretation (again, in their mind). The person brings their find to their local scientist. The local scientist offers a different, yet less fantastic identification. The person, on seeing that the scientist does not agree with them, becomes defensive and/or outraged. Sometimes the scientist never hears from this individual again. Sometimes the scientist will have to deal with this person for the rest of their career.

My first encounter with a person like the Discoverer was back in 1999 when I was still an undergraduate. I was visiting my parents over summer break and joined them on a day of antiquing. I was browsing through the store when my parents called me over to the front counter. They had been talking with the proprietress of the shop, and somehow it came up in conversation that I was studying paleontology. The woman was very excited to talk to me: she had a fossil to show me. Before showing me the fossil, she gave me a long background explanation of finding it in the badlands of southern Alberta (promising). She had even done some preliminary research and thought it might be a scapula from a hadrosaur. Needless to say I was intrigued.

This was my first lesson in fossil identification: the bigger the set-up, the less likely the accuracy of said set-up. Lying on the counter in front of me was a glacial erratic composed of metamorphic rock. There were even garnet crystals embedded in the surface. The only aspect of this specimen that was bone-esque was that it was elongate. During my examination the proprietress stared at me with eager anticipation.

I tried my hand at tact and diplomacy (also a first). "It does have a similar shape to a bone (it really didn't, but I was trying to let her down gently), but there is no bone structure present. This is a metamorphic rock that is shaped like a bone." I pointed out the different minerals. I showed her the garnet crystals, which I thought were cool because they were of a decent size and a deep red. I told her what bone texture looks like.

She wasn't impressed. The eagerness was quickly replaced with indignant exasperation. "I thought you were a paleontologist. Clearly you don't know what you're talking about," she huffed.

I'm sure my expression was one of stunned surprise. "Well, I do, and that's not bone," was my only response. (Note: I was taken off guard by her response, and I bypassed diplomacy and defaulted to direct and blunt. I probably should have held on longer to try to educate her.) She bundled up her prize and walked away. Since my first encounter I have had many people bring in non-fossils for identification, and some are pretty darn convincing. There was a rock shaped like Pac-Man that just had to be a skull (that one was not convincing, but I had to mention it because it still amuses me.) Concretions are brought in as either eggs or turtles. A piece of railway slag looked like a bison skull. There are river-eroded igneous and metamorphic rocks that look like bone. I was once asked to identify a Bigfoot tooth (piece of calcite).

The pseudo-egg on the right is the most convincing: there are even "pores" present.
One of our largest pseudo-turtles. Concretions often preserve with what looks like shell ornamentation.
OK Nature: now you're just f**king with me. The most convincing pseudo-bone I have ever seen.
What would be the "medial" side if this were something other than eroded metamorphosed sandstone.
These wonderfully deceiving rocks are pseudofossils. I make it a point to always have some pseudofossils on hand for when someone brings in a fossil that is not a fossil. Being able to explain to the person that they are not the only ones who were "tricked" by a funky rock can go a long way to ease the disappointment. This works beautifully with kids. I love identifying rocks and fossils for kids. Even when they bring in a non-fossil, it always cheers them up to hear they have a pseudofossil.

Seeing orderly shapes where no shapes exist is the well-documented phenomenon of pareidolia: the phenomenon of perceiving patterns in randomness. One well-known example of pareidolia is the "Face on Mars" which, on thorough examination, was only an illusion visible from one angle. Our brains are likely hard-wired to do it. If you see a pony in the clouds it's your brain trying to organize information that seems unordered. Pareidolia can also send our species' reasoning skills down the path of the illogical. Dieties appear in toast and other starchy foods. A wisp of mist in a photograph becomes a shrouded ghost (same with camera straps, insects, dust specs illuminated by flash, water spots or smudges on lenses...). Skeletons are seen on Mars.

Unfortunately, pareidolia often teams up with pseudo-reasoning to create the most frustrating experience a scientist can face when working with the public. Convinced that their eyes and brains would never deceive them, those being coached by the Pareidolia-Pseudoreasoning Double Team not only are damned sure they have something, but there is no amount of evidence to the contrary will sway their interpretation. This is what science ISN'T. Science does not cherry-pick the data to support a pre-set interpretation. A proper scientific investigation looks at all the available data and then sees which interpretation best explain the data. Unfortunately, this is not how science is viewed by society: based on the Comments section of science articles, scientists are only publishing the data that support their ideas. By extension, that's how one engages in a scientific discussion.

I will be the first to admit that when I was an ichnology newbie I used pareidolia often. My mentors, being the very patient educators that they are, checked out every depression (for natural moulds) and odd-shaped sedimentary river rock (for natural casts) I though might be a track. For each pseudo-ichnite (there were many explanations that started with the phrase "That's very interesting, but...") they would carefully explain why it wasn't an actual ichnite. I think ichnofossils are more prone to pareidolia than other fossil types. Ichnofossils are, in essence, shapes in the rock (you can't look for bone texture in an ichnite), but they are shapes made by specific biologic processes.

I continued to ask questions about objects I found when prospecting, but I also paid close attention to what my mentors were showing me when we encountered actual ichnofossils. I studied the tracks of extant animals in various different sediment types. Eventually I saw enough ichnites of many different types (mammal, dinosaur, bird, turtle, crocodile, pterosaur, invertebrate burrows, etc.) that my brain began to recognize those patterns: I had developed a search image.

Does pareidolia still creep in when I am prospecting? I admit that it does, but I now use it as a prospecting aid. When I'm prospecting, I give my brain two tasks. One, I let it process shapes in the rock. If my brain applies order to the chaos of a rock ("Hey Strange Woman, that looks footprint-esque,") I stop and examine it more closely. Two, I use the accumulated experience of having seen what is and isn't a track and look for ichnologic indicators (repeated biologic structure such as digits, slide marks, skin impressions, etc.). The process is now automatic for me, but in the beginning it was a learning curve with which I struggled. If I can't apply biologic or evidence-based support to the pattern detected by my brain, I move on.

The difference between someone who is truly trying to learn and someone who is just trolling to "win a debate" with a scientist is what that person does when they are told their discovery is not a fossil. If a recent thread I've been following on a paleontology Facebook page is any example, there is no amount of data or explanation that can re-train a brain devoted to the Pareidolia-Pseudoreasoning Double Team.

"But Strange Woman", some may ask, "surely these people just need to be educated about the facts and the scientific method?" A more likely question might be "Why feed these trolls?"

Most of the scientists I know are natural educators. They see every opportunity to turn a seeming frustrating conversation into a teachable moment. When misinformation rises from the depths like a pseudological Kraken, scientist are there with the recent data (and their years of experience) to slay the Pseudoscience Beast. What is sad is that these efforts might actually feed the Beast. A recent study (link here: it's pay-walled) on the political perceptions of the public suggests that offering corrections to previously read inaccurate statements failed to reduce misperceptions (1). In fact, the study also shows that corrections tended to strengthen political misperceptions rather than correct them. If people's minds work the same way with misinformation in science (I would love to read a study on that), what hope do we have of countering misinformation, especially when those misinformation is potentially detrimental (e.g. climate change deniers, misinformation on reproductive health, anti-vaxxers, etc.)?

It's likely we will never find the magic formula of words that will break through that armor of pseudologic. That won't stop us from trying. No matter what, scientists will continue to ensure that the correct information is out there for those not caught on the circular reasoning merry-go-round.

So, Dear Reader, we are more than happy to take a look at your funky specimen. Please don't be insulted if it is not a fossil. We're not trying to trick you, just teach you. We want you to develop a fossil search image and discover something cool for science!


1. Nyhan, B. and J. Reifler. 2010. When corrections fail: the persistence of political misperceptions. Political Behavior 32(2):303-330.


  1. Great post! I had a friend show me two "fossils" she had saved over the years. One at quick glance looked like a little like maxilla and had a nice skull-y color and texture. It was a eroded piece of internal ammonite shell. The other didn't look at all like a fossil. I strongly suspect it's a stone axe head. But I'm no archaeologist so it could be rebound pareidolia...

    1. I've had a few ammonite fossils come in for identification, and usually as either vertebrae or as maxillae/dentaries. One instance was of an ammonite with ornamentation, where the ornamentation was interpreted as skull horns. Those instances the discoverers seem to leave a bit more satisfied: they still have a fossil, just not the fossil they thought they had.

      I love the term "rebound pareidolia."