Urolite is a term compound of two Greek words, uro- meaning "urine

Urine

Urine is a typically sterile liquid by-product of the body that is secreted by the kidneys through a process called urination and excreted through the urethra. Cellular metabolism generates numerous by-products, many rich in nitrogen, that require elimination from the bloodstream...

" and lithos meaning "stone

STONe

is a Japanese manga written and illustrated by Sin-Ichi Hiromoto. Kodansha released the two bound volumes of the manga on April 23, 2002 and August 23, 2002, respectively.The manga is licensed for an English-languague released in North America be Tokyopop...

" and was first used to differentiate the fossil of a nonliquid urinary secretions, produced by some groups of reptiles

Reptile

Reptiles are members of a class of air-breathing, ectothermic vertebrates which are characterized by laying shelled eggs , and having skin covered in scales and/or scutes. They are tetrapods, either having four limbs or being descended from four-limbed ancestors...

, in relation to coprolite

Coprolite

A coprolite is fossilized animal dung. Coprolites are classified as trace fossils as opposed to body fossils, as they give evidence for the animal's behaviour rather than morphology. The name is derived from the Greek words κοπρος / kopros meaning 'dung' and λιθος / lithos meaning 'stone'. They...

s. The first evidence of occurrence of liquid waste elimination attributed to a dinosaur was presented to the public in 2002, but no scientific paper had been reported a fossil evidence of liquid waste of tetrapods

Tetrapod

Tetrapods are vertebrate animals having four limbs. Amphibians, reptiles, birds and mammals are all tetrapods; even snakes and other limbless reptiles and amphibians are tetrapods by descent. The earliest tetrapods evolved from the lobe-finned fishes in the Devonian...

 elimination to assume that dinosaur

Dinosaur

Dinosaurs are a diverse group of animals of the clade and superorder Dinosauria. They were the dominant terrestrial vertebrates for over 160 million years, from the late Triassic period until the end of the Cretaceous , when the Cretaceous–Paleogene extinction event led to the extinction of...

s urinated.

In 2004, a paper of the paleontologist Marcelo Adorna Fernandes brought a studied of trace fossil

Trace fossil

Trace fossils, also called ichnofossils , are geological records of biological activity. Trace fossils may be impressions made on the substrate by an organism: for example, burrows, borings , urolites , footprints and feeding marks, and root cavities...

s that had been preserved in three aeolian flagstone

Flagstone

Flagstone, is a generic flat stone, usually used for paving slabs or walkways, patios, fences and roofing. It may be used for memorials, headstones, facades and other constructions. The name derives from Middle English flagge meaning turf, perhaps from Old Norse flaga meaning slab.Flagstone is a...

s.
These trace fossils show a pattern that could be formed by an abundant falling stream of fluid and that is different from the structures described before in other occurrences in the paleontological records. The aspect of these urolites is very similar to the deformation caused in the soil by elimination of liquid wastes of modern ostrich

Ostrich

The Ostrich is one or two species of large flightless birds native to Africa, the only living member of the genus Struthio. Some analyses indicate that the Somali Ostrich may be better considered a full species apart from the Common Ostrich, but most taxonomists consider it to be a...

es, and certain groups of dinosaurs could have a similar urinary physiology. These urolites are the first evidences of the liquid waste attributed to dinosaurs.