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Adam Maloof/NSF
Stromatolite column of bacterial mats in Australia; sponge fossils are between stromatolites.
Situ Studio/NSF
Stacking autotraced rock sections results in this image; the elliptical fossil is clearly visible.
Catherine Rose/NSF
Looking east from a low-flying plane over the Little Bunkers Ranges in South Australia.
Adam Maloof/NSF
Below a cliff, a reddish bed is one of many stromatolite bioherms containing fossil sponges.
Maloof Lab/Situ Studio/NSF
Limestone rock image containing fossils.
Adam Maloof
The stratigraphic section where the fossil sponges were discovered.
Adam Maloof
View of the Trezona Formation in the West Central Flinders Ranges, South Australia.
Adam Maloof/NSF
Researchers Laura Poppick and Blake Dyer hike down a stromatolite reef in South Australia.