Physiological energetics of the intertidal sea anemone Anthopleura elegantissima : III. Biochemical composition of body tissues, substrate-specific absorption, and carbon and nitrogen budgets.

Lipid is the major energy storage molecule, and protein is highly conserved when food availability is low in high- and low-intertidal individuals of Anthopleura elegantissima. Under laboratory conditions zooxanthellae were lost from anemones, and tissue carbohydrate was mobilized to support metabolic demands. Routine catabolic requirements for carbohydrate are probably met by translocated photosynthate. Substrate-specific absorption efficiencies were greater than 95% for protein and lipid, but considerably lower (10 to 60%) for carbohydrate. This pattern of absorption is directly related to very low levels of dietary carbohydrate compared to the other substrates. High-intertidal anemones absorbed more lipid than low-intertidal anemones. Integrated budgets for organic nitrogen, the first reported for any cnidarian, indicate that low-intertidal anemones require larger daily rations than high-intertidal anemones to meet their higher metabolic demands for protein. These results are considered in relation to potential importance of zooxanthellae in nutrient cycling.

A conceptual framework for organismal biology: linking theories, models, and data.

Implicit or subconscious theory is especially common in the biological sciences. Yet, theory plays a variety of roles in scientific inquiry. First and foremost, it determines what does and does not count as a valid or interesting question or line of inquiry. Second, theory determines the background assumptions within which inquiries are pursued. Third, theory provides linkages among disciplines. For these reasons, it is important and useful to develop explicit theories for biology. A general theory of organisms is developed, which includes 10 fundamental principles that apply to all organisms, and 6 that apply to multicellular organisms only. The value of a general theory comes from its utility to help guide the development of more specific theories and models. That process is demonstrated by examining two domains: ecoimmunology and development. For the former, a constitutive theory of ecoimmunology is presented, and used to develop a specific model that explains energetic trade-offs that may result from an immunological response of a host to a pathogen. For the latter, some of the issues involved in trying to devise a constitutive theory that covers all of development are explored, and a more narrow theory of phenotypic novelty is presented. By its very nature, little of a theory of organisms will be new. Rather, the theory presented here is a formal expression of nearly two centuries of conceptual advances and practice in research. Any theory is dynamic and subject to debate and change. Such debate will occur as part of the present, initial formulation, as the ideas presented here are refined. The very process of debating the form of the theory acts to clarify thinking. The overarching goal is to stimulate debate about the role of theory in the study of organisms, and thereby advance our understanding of them.

IRREVERSIBLE NONGENETIC TEMPERATURE ADAPTATION OF OXYGEN UPTAKE IN CLONES OF THE SEA ANEMONE HALIPLANELLA LUCIAE (VERRILL).

1. Isogenic clones of H. luciae were raised at each of two developmental temperatures, 18° and 28° C. Despite prolonged acclimation to common thermal conditions, oxygen uptake rates differ according to the temperature of reproduction, regeneration and development. 2. The effects of developmental temperature, however, are masked by body size differences. Only when this variable is eliminated can the underlying effect of developmental temperature be detected. 3. The irreversible change is not due to an increase in the gas exchange surface area at the primary site of O2 uptake, the tentacles. 4. No qualitative changes in banding patterns for five enzymes (HK, PGI, IDH, MDH, G-6-PDH) were found.