Variations in life history define key comparative and evolutionary biological questions, important for understanding the mechanisms of mammalian evolutionary divergence, developmental adaptability and plasticity. In this regard, the differences among predominantly altricial and precocial species represent a particularly significant, if still poorly understood and contested case. Here, it will be shown how the classical analysis of such ontogenetic variations, going back to the semantic biology of A. Portmann, can be expanded and synthesized with comparative physiological approaches, based on the negentropic (...) theory of ontogeny by I. A. Arshavsky and his school. In this little received but pioneering tradition, extensive comparative and experimental investigations were carried out on the role of musculoskeletal systems and stressors in driving life history variations, particularly in the altricial-precocial spectrum. As shown by Arshavsky and co-workers, by focusing on general allometric regularities, the approximations based on the classical energy rules of surface and mass offer valuable benchmarks, but also predictions that are frequently violated by the variability of physiological and metabolic scaling relationships among altricials and precocials, and thus, a complex and historical approach is needed to describe their local physiological mechanisms and systemic regularities. This paper shows how Arshavsky’s findings and framework can play an integrative role in this context, potentially helping to bridge the mainly descriptive approach of semantic morphology, as developed by Portmann’s school, with the more functional explanations predominating current ecology and life history theory. These problems can be important for biosemiotics by highlighting the contingent, activity-dependent, and surplus anabolic stress mechanisms underlying diversification in eutherian developmental systems and possibly, the epigenetic evolution of pace-of-life syndromes. (shrink)

This paper focuses on the links between Jakob von Uexküll’s theoretical biology and Adolf Portmann’s conception of organic life. Its main purpose is to show that Uexküll and Portmann not only share a view of the living being as an autonomous and holistically organized entity, but also base this view on the seminal idea of the subjectivity of the organism. In other words, the respective holistic principles securing the autonomy of the living being—the Bauplan, for Uexküll; the Innerlichkeit, for Portmann—share (...) an essentially subjective character. Such principles, indeed, express themselves in a centrally directed and formative way; moreover, in organisms endowed with a central nervous system, they also extend their influence on the overt behavioral sphere and on the organism’s capacity to give meaning to the surrounding reality. The conclusion of the article will show how, though starting from this common background, the two authors develop divergent positions on the issue of the anthropological difference. If Portmann emphasizes the special status of the relationship between the human animal and the world, Uexküll tends to see a substantial continuity in the biosemiotic processes through which human and non-human animals constitute their species-specific worlds of experience. (shrink)