定義: A taxon is Extinct when there is no reasonable doubt that the last individual has died. A \r\ntaxon is presumed Extinct when exhaustive surveys in known and/or expected habitat, \r\nat appropriate times (diurnal, seasonal, annual), throughout its historic range have failed \r\nto record an individual. Surveys should be over a time frame appropriate to the taxon’s life cycle and life form.
定義: The marine benthic biome (benthic meaning 'bottom') encompasses the seafloor and includes such areas as shores, littoral or intertidal areas, marine coral reefs, and the deep seabed.
定義: muscular waves propelling an animal over a mucus layer overlaying the substrate; alternating regions of muscular contraction and expansion create traveling waves that shear the mucus, resulting in translation of the animal.
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)