KOZLOWSKI, Jan; Jagiellonian University, Institute of Environmental Sciences, Krakow, Poland: The meaning of terms �growth rate� and �adult size� in determinate and indeterminate growers

Basically all organisms can be classified as determinate growers if their growth stops or almost stops at maturation or indeterminate growers if growth is still intense after maturation. Adult size for determinate growers is relatively well defined, whereas in indeterminate growers usually two measures are used: size at maturation and asymptotic size. The latter term is in fact not a direct measure but a parameter of a specific growth equation, most often Bertalanffy�s growth curve. Growth rate in determinate growers depends on physiological constraints as well as on investments in repairs and other mechanisms that improve future survival. Growth rate in indeterminate growers consists of two phases: juvenile and adult. Mechanisms determining juvenile growth rate are similar as in determinate growers, whereas allocation to reproduction (dependent on external mortality rate) seems to be main factor limiting adult growth. In many papers these two kinds of organisms are mixed, which often causes misinterpretation of field data. The reasons why some organisms stop growing after maturation and others continue to grow will be also discussed.