Fossil feces from a carnivorous dinosaur. This specimen was found in southwestern Saskatchewan, Canada. Scale bar is 15 centimeters (6 inches) long.

The Saskatchewan coprolite is an elongated, fractured mass of rock that is approximately 44 x 16 x 13 centimeters (17 x 6 x 5 inches). About 200 associated fragments weathered downslope from the larger mass and would have contributed to the original volume of the feces—estimated to have been over 2.4 liters (2-1/2 quarts). The specimen contains fragments of bone, and its great size distinguishes it as the largest individual carnivore coprolite yet described. It is usually very difficult to determine the identity of the producer of a coprolite, but the great size and geologic and temporal context of this specimen indicate a tyrannosaur origin. Of the carnivorous dinosaurs (theropods) and crocodilian species known from the area in which this specimen was found, only Tyrannosaurus is likely to have produced such a sizable fecal mass.

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