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Illuminating Fossils: Light’s Importance in Paleontology

Emily Hughes brings us tales of adventure and discovery from the Australian Outback as she and her mother search for unbelievably ancient fossils. Her team digs up the creatures that form the evolutionary boundary between microorganism and animal—the Ediacaran biota. 

Any professional photographer can tell you how important light is for their job. The right lighting can illuminate the tentacles on an octopus, show the shadows on mountains, or soften the features of a human being. As the light changes throughout the months, days and hours, the way we perceive the world also changes. But light isn’t important solely for aspiring photographers and photojournalists, it’s important for anyone with a camera, and paleontologists who just want to find fossils.

A cascade of light and color in the Outback. (Photo credit Mary Droser)
A cascade of light and color in the wintry Outback. (Photo credit Mary Droser)

Mary Droser, a professor of Paleontology at the University of California, Riverside (and also my mom), wakes up each morning and immediately looks out the window at the sky. If the day is sunny, she is extremely happy, and if it is cloudy, she is not. This is because the sky is one of the most important (and variable) aspects of getting our job here done. With good lighting, fossils are illuminated so that each curve and line is prominent in the rock. We can take photos of the fossils, log them, and map the beds when the lighting is nice, and when it is not we have a whole suite of activities reserved for cloudy days.

Here is a photo of a Dickinsonia in bad lighting, in the middle of the afternoon on a cloudy day.

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A fossil in darkness, faintly seen… (Photo credit Emily Hughes)

Now, here is another photo of the same Dickinsonia, still in the afternoon but with a clear sky.

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…Gives way to light that has shined since the dawn of life… (Photo credit Emily Hughes)

And lastly, here’s a photo of the Dickinsonia at dusk, the best time to take photos, along with early morning. Why is this the case? Well, the lines, bumps and curves of a fossil are all but invisible during the afternoon with the sun beating down on them. But in the morning and late afternoon, they are shadowed, so we can see where they are and what they look like. It’s also a good way to take photos that actually depict the whole fossil, and not just a weak outline.

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…Revealing a solid form lurking in the depths of time. (Photo by Emily Hughes)

If we search for fossils on a cloudy day in one spot, and then again in the same spot on a sunny day, often we see many more than before. Areas that can look depleted 0f any 560-million-year-old organisms one hour are bursting with fossils the next.

We find ways to have fun on cloudy days, too. Recently, there was a rain storm, and a huge rainbow appeared out of the dreary sky. Everyone screamed, “Rainbow!” and rushed to take photos of it, because rainbows are a bit of a rare occurrence out here.

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The infamous double-rainbow graces the team with its presence. (Photo by Emily Hughes)

Even rainbows are an example of the importance of light. If light isn’t important because of its use in photography, paleontology, and just seeing things in different ways, then surely—surely it’s important because of its beauty.

Read More by Emily Hughes