Määritelmä: The number of fossil occurrences in the Paleobiology Database (https://paleobiodb.org) that are identified as belonging to a particular taxon or any of its subtaxa.
Määritelmä: Description of the relationships among individuals within a population of organisms, including reproductive relationships (mating system), relationships within each sex, adult – young interactions, helpers and cooperation (group living).
Määritelmä: where individuals of the same species (conspecifics), maintain spatial proximity with one another over time with mechanisms of social attraction
Määritelmä: A group of species that exploit the same food resources, and/or use the same feeding or foraging methods. http://en.wikipedia.org/wiki/Guild_(ecology)