"The Mesozoic trend to sauropod gigantism led to the evolution of immense microbial vats unequalled in modern land animals."

~ David M.Wilkinson, University of Lincoln (2012)

Scientifically speaking, coprolites are fossilized poop. Over millions of years, minerals, such as chalcedony and quartz, replaced the original organic material. This process creates a rich, colorful matrix that allows us to study the diet and lifestyle of long-extinct creatures.

Coprolites can come from reptiles, dinosaurs, and even ancient mammals. Depending on their origin, coprolites may contain a variety of minerals such as phosphorus and calcium. Scientists use these trace fossils to help identify the species responsible for the droppings and to learn more about their diet.

Our specimens come from the Morrison Formation in Utah. One of the most studied fossil beds of the upper Jurassic Period, the region was once home to a large floodplain ecosystem 150,000,000 years ago. Coprolites of this size are typically attributed to sauropods.

This image provides incredible detail of several curious samples: (a) conifer wood fragments (b) decayed wood fragment. (c) irregular, knobby cuticle (d-f) cylindrical appendage embedded in coprolitic groundmass (e) thin section of appendage shown in fig d. (f) higher magnification photomicrograph of appendage cuticle in fig d. (g-h) small cuticle fragment (h) Scanning electron micrograph of specimen in (g) revealing perpendicular diagenetic growth of crystals (i-j) Thin section showing a >6 mm long cuticle fragment embedded in fecal groundmass. Yellow rectangle indicates area shown in (i) and blue rectangle shows area of microprobe maps. (j) Close-up image of cuticle in (i). Exocuticle is at right of photo and probable pores are evident. (k-m) distributions of calcium, magnesium, and phosphorus of cuticle in (i). Brighter colours indicate higher element concentrations. Note that distributions of magnesium and phosphorus follow the laminar structure of the cuticle.