定義： Component found in mineralized skeletal tissue, (a specialized form of biogenic tissue in which the extracellular matrix is mineralized, and which functions in mechanical and structural support.)
定義： 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.
定義： 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)
定義： The institution that holds a type specimen for a given species. The recommended best practice is to use the identifier in a collections registry such as the Biodiversity Collections Index (http://www.biodiversitycollectionsindex.org/).
定義： An eye that consists of a cluster of three or four pit eyes that form a single structural unit but are separated from one another by pigment layers
