Humanity, like all other species of Earth before and with us, is evolving — and evolution, for humans as for all species, is neither predictably linear nor solely Darwinian. Earth’s nearly four billion years of evolutionary experience reveals reliable patterns that give us hope, inspiration and valuable guidance for getting ourselves through the unprecedented confluence of enormous crises in which we humans quite suddenly find ourselves. Here we see the evolutionary Big Picture, including the amazingly complex lives of our remotest bacterial ancestors, who had Earth to themselves for fully half of evolution, and much of whose experience we seem to be mirroring now. They engaged in hostilities, generated global crises of hunger and pollution as great as ours today, and solved them without benefit of brain! Along the way they invented electric motors, atomic piles and the first World Wide Web of DNA exchange; then, in the greatest of all evolutionary ventures, formed cooperatives that became nucleated cells. These cooperatives were the basis for the evolution of our own hundred-trillion-celled human bodies, which role model amazingly sustainable economies. Learning from newly revealed problems and solutions in biological evolution, we too are finding out how to survive and even thrive into a better future despite — perhaps because of — our greatest challenges. That would indeed be cause for celebration.
It is shown how both the principles of extremum of entropy production, which are often used in the study of complex systems, follow from the maximization of overall system conductivities, under appropriate constraints. In this way, the maximum rate of entropy production (MEP) occurs when all the forces in the system are kept constant. On the other hand, the minimum rate of entropy production (mEP) occurs when all the currents that cross the system are kept constant. A brief discussion on the validity of the application of the mEP and MEP principles in several cases, and in particular to the Earth’s climate is also presented.
In a recent paper  Reis showed that both the principles of extremum of entropy production rate, which are often used in the study of complex systems, are corollaries of the Constructal Law. In fact, both follow from the maximization of overall system conductivities, under appropriate constraints. In this way, the maximum rate of entropy production (MEP) occurs when all the forces in the system are kept constant. On the other hand, the minimum rate of entropy production (mEP) occurs when all the currents that cross the system are kept constant.
In this paper it is shown how the so-called principle of “minimum energy expenditure” which is often used as the basis for explaining many morphologic features in biologic systems, and also in inanimate systems, is also a corollary of Bejan’s Constructal Law .
Following the general proof some cases namely, the scaling laws of human vascular systems and river basins are discussed as illustrations from the side of life, and inanimate systems, respectively.
Excerpted from: http://library.fora.tv/2011/10/26/Growth_Has_an_Expiration_Date Tom Murphy is an associate professor of physics at the University of California, San Diego. He currently leads a project to test General Relativity by bouncing laser pulses off of the reflectors left on the Moon by the Apollo astronauts, achieving one-millimeter range precision. Murphy’s keen interest in energy topics began with his… Read More