Määritelmä: 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.
Määritelmä: overall repetitive or reflective pattern in the body of one individual of this taxon. eg: bilateral symmetry, rotational symmetry, radial symmetry
Määritelmä: a type of pectoral-fin-based swimming, also known as mobuliform locomotion. Lower frequency than fin undulation; can be described as the production of less than half a wave on the fin, similar to a bird wing flapping. Pelagic stingrays use oscillatory locomotion.
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
