Scientists say Charles Darwin’s evolutionary law goes beyond living beings
Evolution is not limited to living beings as minerals evolve, too
A new paper in the Proceedings of the National Academy of Sciences describes “a missing law of nature,” recognising for the first time an important norm within the natural world’s workings.
In essence, the new law states that complex natural systems evolve to states of greater patterning, diversity, and complexity. In other words, evolution is not limited to life on Earth, it also occurs in other massively complex systems, from planets and stars to atoms and minerals, says a press statement.
The paper has been authored by a nine-member team, leading scientists from the Carnegie Institution for Science, the California Institute of Technology (Caltech) and Cornell University and philosophers from the University of Colorado.
The statement adds that the laws of nature, motion, gravity, electromagnetism and thermodynamics, codify the general behaviour of various macroscopic natural systems across space and time.
Law of increasing functional information
The “law of increasing functional information” published today complements the 2nd law of thermodynamics, which states that the entropy (disorder) of an isolated system increases over time (and heat always flows from hotter to colder objects.
The statement adds that “macroscopic” laws of nature describe and explain phenomena experienced daily in the natural world. Natural laws related to forces and motion, gravity, electromagnetism, and energy, for example, were described more than 150 years ago.
The new work presents a modern addition, a macroscopic law recognising evolution as a common feature of the natural world’s complex systems. The scientists say that they are formed from many different components, such as atoms, molecules, or cells, that can be arranged and rearranged repeatedly.
The report adds that they are subject to natural processes that cause countless different arrangements to be formed and only a small fraction of all these configurations survive in a process called “selection for function.”
Regardless of whether the system is living or non-living, when a novel configuration works well and function improves, evolution occurs, say the scientists.
The statement adds that the Law of Increasing Functional Information, developed by the scientists, states that the system will evolve if many different configurations of the system undergo selection for one or more functions.
“An important component of this proposed natural law is the idea of ‘selection for function,’” says Carnegie astrobiologist Dr Michael L Wong, first author of the study.
The report adds that in the case of biology, Darwin equated function primarily with survival, the ability to live long enough to produce fertile offspring. It says that the new study expands that perspective, noting that at least three kinds of function occur in nature.
The most basic function is stability as stable arrangements of atoms or molecules are selected to continue. Also chosen to persist are dynamic systems with ongoing supplies of energy. The third and most interesting function is “novelty”, the tendency of evolving systems to explore new configurations that sometimes lead to startling new behaviours or characteristics.
The statement adds that life’s evolutionary history is rich with novelties, photosynthesis evolved when single cells learned to harness light energy, multicellular life evolved when cells learned to cooperate, and species evolved thanks to advantageous new behaviours such as swimming, walking, flying, and thinking.
Evolution occurs in minerals, too
The same sort of evolution happens in the mineral kingdom. The earliest minerals represent particularly stable arrangements of atoms. Those primordial minerals provided foundations for the next generations of minerals, which participated in life’s origins. The evolution of life and minerals are intertwined, as life uses minerals for shells, teeth, and bones.
“Indeed, Earth’s minerals, which began with about 20 at the dawn of our Solar System, now number almost 6,000 known today thanks to ever more complex physical, chemical, and ultimately biological processes over 4.5 billion years,’’ says the report.
In the case of stars, the paper notes that just two major elements, hydrogen and helium, formed the first stars shortly after the big bang. Those earliest stars used hydrogen and helium to make about 20 heavier chemical elements. And the next generation of stars built on that diversity to produce almost 100 more elements.
“Charles Darwin eloquently articulated the way plants and animals evolve by natural selection, with many variations and traits of individuals and many different configurations,” says co-author Robert M Hazen of Carnegie Science, a leader of the research.
“We contend that Darwinian theory is just a very special, very important case within a far larger natural phenomenon. The notion that selection for function drives evolution applies equally stars, atoms, minerals, and many other conceptually equivalent situations where many configurations are subjected to selective pressure,” he adds.
“In this new paper, we consider evolution in the broadest sense, change over time, which subsumes Darwinian evolution based upon the particulars of ‘descent with modification. The universe generates novel combinations of atoms, molecules and cells. Those combinations that are stable and can go on to engender even more novelty will continue to evolve. This is what makes life the most striking example of evolution, but evolution is everywhere,” adds Wong.
The press statement adds that the new paper will help in understanding into how differing systems possess varying degrees to which they can continue to evolve. “Potential complexity” or “future complexity” have been proposed as metrics of how much more complex an evolving system might become.
