First published 2 September 2013
Heterogeneity and complexity of a simulated terrestrial environment account for the superiority of the atruistic gene
Tadao Maekawa, Manabu Honda, Norie Kawai, Emi Nishina, Osamu Ueno, Tsutomu Oohashi
Recent research on the notion of altruism in terrestrial life has focused on certain altruistic behaviors, which are regarded as beneficial to animal life, especially with respect to individual animal species. Such findings throw light on individualoriented mechanisms and their evolution in helping to clarify so-called intentional interactions between individuals based on discrimination of other individuals and remembered information as advanced by developments in biological information processing, ranging from molecular recognition to activation of the neural system. In 2006, Nowak classified these mechanisms into five types. In the current study, we have zeroed in on the process of autolysis universally observed in all terrestrial lives, as characterized by genetically programmed death accompanied by altruistic self-decomposition, whose model we call the "programmed self-decomposition model (PSD Model)". In our view, altruistic phenomena target no specific individuals yet prove beneficial to the ecosystem, in part and as a whole. Using our PSD Model we ran evolutionary simulations of altruistic phenomena in the SIVA Series, which is an artificial life system designed to resemble a terrestrial ecosystem, and one that excludes both discrimination of individuals and interactions between individuals. In our simulations no individual-oriented evolutionary mechanism was observable while the ecosystem-oriented mechanism positively contributed to the evolution of the altruistic gene. Our research has thus sought to determine factors that promote superior evolutionary characteristics of altruistic phenomena in a terrestrial ecosystem model. The current study argues that the high heterogeneity and complexity of a terrestrial environment and the eternality of evolutionary time play an important role in the selective process of programmed death in the terrestrial ecosystem, which is accompanied by altruistic selfdecomposition. Based on the above findings, we investigated the inseparable relationship existing between a terrestrial ecosystem and the altruistic gene.