SUMMARY: Jean-Bernard Caron, Curator of invertebrate Palaeontology at the Royal Ontario Museum, explains the process of getting from a flat fossil to a 3-D reconstruction of the animal. (2:24)

Caron holds the flat fossil up to the camera
DESCRIPTION: Caron holds the flat fossil up to the camera

"So this is a specimen called Sidneyia inexpectans from the Burgess Shale. When I tilt the specimen you can see the difference in reflectivity and the very fine details. This is a fossil that is very flat, which originally was three-dimensional. How do we go from a fossil that is flat, to a three-dimensional object? Well, scientists like myself use many specimens, some preserved dorsal-ventrally, some preserved laterally to be able to reconstruct the animals in three dimensions. It takes a lot of patience and care to be able to look at different specimens, and usually we have to write very detailed accounts of our research in a monograph series like this one."

Caron points to illustrations in a book
DESCRIPTION: Caron points to illustrations in a book

"This is a study by Dr. Bruton, published in 1981, and after all this description, Bruton draws some schematics of what he thought to be the organization of the fossil of this animal in three dimensions. So he reconstructed the animal with the dorsal view, the ventral view and the lateral view. But this is a two-dimensional drawing. And we are interested, obviously, to better understand what the animal would have looked like with a three dimensional model. We basically have to cast and mold some of these elements and put them together."

Caron holds up the 3-dimensional model, ventral view
DESCRIPTION: Caron holds up the 3-dimensional model, ventral view

"So we are lucky at the ROM here to have one of these models of Sidneyia inexpectans; this is the one we have here and this was created during that study. This is a ventral view of the animal showing the antennae at the front, and all the series of appendages at the back here. All the structures are ventral, and you can see the gill, the very small elements that are reconstructed here."

Dorsal view
DESCRIPTION: Dorsal view

"So I'm going to flip this animal and you can see on the dorsal view, the smooth surface of the animals, the eyes here, and again the antennae."

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