Sockeye salmon depletion in energy stores. Fat, protein, and somatic energy stores decrease from the final moments in marine migration through freshwater entry, spawning, and death. Sockeye salmon do not feed during reproduction. Feeding ends once they enter into freshwater, which can be several months before spawning. Embryos are maintained with only endogenous food supplies for about 3–8 months. Reproduction in the sockeye salmon has to be accomplished with the energy stores brought to the spawning grounds. How the salmon use their energy during migration and spawning affects how successful they will be reproductively; energy used for migration cannot also be used
The purpose of a system is what it does be balanced by a more straightforwardly descriptive view. The term is used in many fields including biology and management. The purpose of a system is what it does The purpose of a system is what it does (POSIWID) is a systems thinking heuristic coined by Stafford Beer. Stafford Beer coined the term POSIWID and used it many times in public addresses. In his address to the University of Valladolid, Spain, in October 2001, he said "According to the cybernetician, the purpose of a system is what it does. This is a basic dictum. It stands for bald fact, which makes