Adaptation by means of natural selection depends on the ability of populations to maintain variation in heritable traits. According to the Modern Synthesis this variation is sustained by mutations and genetic drift. Epigenetics, evodevo, niche construction and cultural factors have more recently been shown to contribute to heritable variation, however, leading an increasing number of biologists to call for an extended view of speciation and evolution. An additional common feature across the animal kingdom is learning, defined as the ability to (...) change behavior according to novel experiences or skills. Learning constitutes an additional source for phenotypic variation, and change in behavior may induce long lasting shifts in fitness, and hence favor evolutionary novelties. Based on published studies, I demonstrate how learning about food, mate choice and habitats has contributed substantially to speciation in the canonical story of Darwin’s finches on the Galapagos Islands. Learning cannot be reduced to genetics, because it demands decisions, which requires a subject. Evolutionary novelties may hence emerge both from shifts in allelic frequencies and from shifts in learned, subject driven behavior. The existence of two principally different sources of variation also prevents the Modern Synthesis from self-referring explanations. (shrink)

In biosemiotics, living beings are not conceived of as the passive result of anonymous selection pressures acted upon through the course of evolution. Rather, organisms are considered active participants that influence, shape and re-shape other organisms, the surrounding environment, and eventually also their own constitutional and functional integrity. The traditional Darwinian division between natural and sexual selection seems insufficient to encompass the richness of these processes, particularly in light of recent knowledge on communicational processes in the realm of life. Here, (...) we introduce the concepts of semiotic selection and semiotic co-option which in part represent a reinterpretation of classical biological terms and, at the same time, keep explanations sensitive to semiosic processes taking place in living nature. We introduce the term ‘semiotic selection’ to emphasize the fact that actions of different semiotic subjects (selectors) will produce qualitatively different selection pressures. Thereafter, ‘semiotic co-option’ explains how semiotic selection may shape appearance in animals through remodelling existing forms and relations. Considering the event of co-option followed by the process of semiotic selection enables us to describe the evolution of semantic organs. (shrink)

The final version of the paper is published pp. 117-166 in: Myrdene Anderson and Floyd Merrell (eds.): On Semiotic Modeling . Mouton de Gruyter, Berlin and New York, 1991.

We develop here a semiotic model of evolution. We point out the role of confusion and choice as a condition for semiosis, which is a precondition for semiotic learning and semiotic adaptation. Semiosis itself as interpretation and decision-making between options requires phenomenal present. The body structure of the organism is largely a product of former semiosis. The organism’s body together with the structure of the ecosystem serves also as a scaffolding for the sign processes that carry on the ontogenetic cycle (...) and the organisms’ behaviour, providing the experience-based channels for decision making in the indeterminate situations of choice. The stability and persistence of ontogenesis and behaviour are based on the plasticity, or the multiviality of organic dynamics. The same plasticity or multivial dynamics is providing the material for further potential evolution. Evolution has occurred when some change becomes irreversible via its stabilization, and it usually means a modification of existing constraints, or scaffoldings. Some examples of these processes are described in the article. (shrink)

The threshold from unicellularity to multicellularity has been crossed only in three major living domains in evolution with any lasting success. The hard problem was to create a multicellular self. Such a self is vulnerable to breakdown due to the unavoidable appearance of mutant anarchistic cells, and stringent semiotic scaffoldings had to emerge to prevent this. While a unicellular self may go on to live practically forever, the multicellular self most often must run through an individuation process ending in the (...) death of the individual. Due to basic differences in cells of plants, fungi and animals this individuation process poses very different challenges in the three kingdoms of plants, fungi and animals, and the solutions found to these differences are discussed. In the same time as multicellularity ushered life into the epoch of mortality it logically also led to the appearance of fertilization and thereby the need for a whole new set of elaborate semiotic scaffoldings. Multicellularity also opened the door to the formation symbiotic relations where cells with different genomes might collaborate or at least coexist inside the same body. All in all multicellularity led to an enormous diversification both of morphology space and the space of sensomotoric elaborations. New means for scaffolding of this expansion and diversification of possible life forms into functional patterns called for a corresponding growth in the space of semiotic tools and initiated a growth in semiotic freedom, that has continued to our days. (shrink)