Ichnology is the branch of paleontology that deals with plant and animal traces. These traces are useful because they often hint at the behavior of the organism. The division of ichnology dealing with trace fossils is paleoichnology, while neoichnology is the study of modern traces. Parallels can often be drawn between modern traces and trace fossils, helping scientists to decode the possible behavior and anatomy of the trace-leaving organisms if no body fossils can be found. In a case in which there are trace fossils but no body fossils to represent a given species, an ichnospecies is erected. Ichnotaxa follow different rules in zoological nomenclature than do normal taxa (see trace fossil classification for more information). Ichnological studies are based off of the discovery and analysis of biogenic structures: features caused by an organism while it was still living. Therefore, burrows, tracks, trails and borings are all examples of biogenic structures. A cast or a mold of a dead organism's body is not an examples of a biogenic structure and is therefore non-important to the study of ichnology.
A person whose primary area of study and research is ichnology is known as an ichnologist.