Harold Morowitz, a leading figure in shaping the scientific and popular understanding of the chemical origins of life on Earth, passed away March 22 in Fairfax, Va.
At the time of his passing Morowitz, 88, was the Robinson Professor of Biology and Natural Philosophy at George Mason University and Science Board Chair Emeritus of the Santa Fe Institute.
Read the obituary in the New York Times (April 3, 2016)
A longtime advocate for the science of complex systems, he was among the prominent scientists whose presence bolstered the Institute’s scientific credibility and research during the formative years after the Institute’s founding. He remained an SFI ally and collaborator for 30 years, attracting a number of younger scientists to the Institute and helping firm its programs in biophysics.
“Harold was a key figure and friend in the development and maturation of the Santa Fe Institute – one of those figures who personifies the Institute’s ambition and mission,” says SFI President David Krakauer. “He is greatly missed.”
Morowitz’s career focus was on applying the principles of thermodynamics to the study of living systems, and his talent in describing the important insights at the forefront of biophysics for nearly seven decades influenced generations of scientists who followed him, says longtime friend and collaborator D. Eric Smith, an SFI external professor.
His voice, at once scientifically reasoned and popularly accessible, played a significant role in identifying and isolating promising hypotheses about life’s origins, says Smith. His “continuous out-of-left-field originality” often pointed to unlikely solutions and nudged his colleagues in promising new directions, he adds.
“Harold wasn’t the originator of the most important theories he was interested in,” Smith says. “But he was instrumental in changing people’s minds and in shifting the way they think.”
Morowitz, a child prodigy, began undergraduate school at Yale at the age of 16. Many years later he often told his own undergraduate students the story of his switch from physics to biology. In a freshman physics lab, Morowitz said, he had been paired with another child prodigy, the 15-year-old physics student Murray Gell-Mann.
The two were competitive, with Gell-Mann usually outperforming his lab partner. (Once, Morowitz said, he outscored Gell-Mann on a test by a couple of points, an event he later realized was to be his greatest achievement in physics.) The young Morowitz decided that if that Gell-Mann was a typical physicist, he should change fields. Gell-Mann, another major figure in the Institute’s founding and history, received the Nobel Prize in physics in 1969.
With his unique background, Morowitz the physicist-turned-biologist zeroed in on a key issue at the intersection of the two fields. The 2nd Law of Thermodynamics calls for increasing entropy (disorder) in a closed system, but living systems seem to evolve continually toward ever-increasing order. He joined other biophysicists in noting that patches of increasing order may form within a large closed system – in this case, the universe – without violating the 2nd Law.
He began to focus on how energy pathways might provide the necessary direction for chemical networks to evolve into self-replicating chemical systems and, eventually, living systems. In particular, he resonated with hypotheses that a buildup of energy in a chemical system might drive energy-dissipating pathways that equalize such energy imbalances – in essence, chemical lightning bolts that distributed stored chemical energy more evenly across the system.
His 1968 book Energy Flow in Biology was influential on both the scientific and popular fronts. Its key idea – "the energy that flows through a system acts to organize that system” – was quoted on the inside front cover of Stewart Brand’s magazine The Last Whole Earth Catalog. Some leading biophysicists, among them Eric D. Schneider, have suggested that Morowitz may have discovered a "fourth law of thermodynamics" in proposing that in a steady state system, the flow of energy through the system from a source to a sink will lead to at least one cycle in the system.
Much later, in the 1990s, Morowitz became an advocate of the hypothesis that given early Earth’s mineralogy and energy sources, such dissipative energy pathways could have driven the self-organization of a citric acid cycle – the chemical process of metabolism – but in reverse. In particular, he suggested that the chemical, energy, and temperature conditions near deep-sea hydrothermal vents might have been adequate to jump start the earliest self-replicating biological systems.
Morowitz writings played a significant role in the emergence of the second of two distinct, but both incomplete, candidate explanations for life’s origins: known as “metabolism first” and “RNA world.” These hypotheses became the nuclei of two outspoken scientific tribes, a division that has persisted for decades – although more recent insights and a contemporary focus on common problems may begin to reconcile the scientific differences between the two camps, notes Smith.
SFI External Professor Walter Fontana recalls that Morowitz was spellbound by the idea that the emergence of new phenomena from interactions at any level of description was a “channeling of the infinite possibilities collectively enabled by these interactions into a select few.” This process of disciplining the infinite into the finite Morowitz referred to as “pruning.”
“He therefore sought the pruning law that would get you from the infinite possibilities opened up by chemistry [of the early Earth] to the finite types of self-maintaining chemical networks that catapult the physical world into a pre-Darwinian trajectory of selective chemical accretion and extension until the first appearance of stable reproducing individuality ignites Darwinian selection as we know it,” Fontana says. “Harold believed that the core cycle of present-day metabolism is the only possible outcome of this pre-Darwinian pruning in the space of early-Earth chemistry.”
Morowitz spent most of his career at Yale University, where he was professor of molecular biophysics and biochemistry and served for five years as master of Pierson College. He joined George Mason University in 1988 and was among the founding faculty of the Robinson Professors program, which recruits distinguished faculty from senior positions at other institutions and brings them to GMU to focus on undergraduate teaching.
He helped established the Krasnow Institute for Advanced Study at GMU and served as its founding director from 1993 to 1998.
Morowitz authored or co-authored hundreds of papers in biophysics, biochemistry, and molecular biology. He served as the founding editor of the journal Complexity.
He also is author of numerous books. Among his titles are The Foundations of Bioenergetics, The Facts of Life, Mayonnaise and the Origins of Life, Cosmic Joy and Local Pain, The Beginnings of Cellular Life, The Thermodynamics of Pizza, Entropy and the Magic Flute, The Kindly Dr. Guillotin, and The Emergence of Everything.
His most recent book co-authored with Smith, The Origin and Nature of Life on Earth: The Emergence of the Fourth Geosphere, is due out in May from Cambridge University Press. It explores the origin of life as a planetary process, combining principles from geology, geochemistry, biochemistry, microbiology, evolution, and statistical physics to develop the argument that the emergence of life was a necessary cascade of nonequilibrium phase transitions that opened new channels for chemical energy flow on Earth.
Fontana calls the book Morowitz’s “grand opus,” and in an online review states it is “the most significant book on the origin of life hitherto written.”
Morowitz’s view that life on earth emerged deterministically from the laws of chemistry and physics led him to the conclusion that it is highly probable that life exists widely in the universe.
He was a longtime consultant for NASA and served on the committees that planned the quarantine procedures for Apollo 11 and the biology experiments the Viking probe carried to the surface of Mars. He was a member of the science advisory committee for Biosphere 2.
In 1981 he testified in "McLean v. Arkansas" that creationism should not be taught as science in public schools. Based in part on his testimony, the court ruled that creation science is not science, an outcome that has influenced subsequent rulings around the country on the teaching of creationism in classrooms.
In 1987 at SFI, he organized a summer workshop on the “Matrix of Biological Knowledge.” The workshop was influential in catalyzing what became the field of biological informatics and in fueling some of the Institute’s emerging research threads in origins of life, artificial life, and autocatalytic loops, to name a few.
In the mid 2000s, Morowitz was principal investigator on the multi-institution NSF-funded grant “From Geochemistry to the Genetic Code,” nucleated at the Santa Fe Institute. As part of the grant, a sweeping exhibit on life’s origins was developed by students at New Mexico Highlands University in partnership with the New Mexico Department of Cultural Affairs. The exhibit is on display at the New Mexico Museum of Natural History & Science in Albuquerque.
During his seven-decade career, Morowitz influenced the thinking of many scientists. Tom Knight, a pioneer in synthetic biology, for example, credits Morowitz’s writings for convincing him that the mysteries of biology could be unraveled in the service of human technology.
Carnegie Institution geologist Robert Hazen has noted that a naive question Morowitz asked him during a 2006 cocktail party changed Hazen’s thinking about early earth’s mineralogy, leading to important new ideas about the co-evolution of minerals and biological systems.
Morowitz’s book Foundations of Bioenergetics played a major role in helping biologists writ large understand relevant issues in basic physics, says Smith.
But Morowitz’s greatest impact, notes Smith, might have been convincing generations of scientists that questions about the origins of life are worthy of their careers. Many SFI scientists, directly and indirectly, benefited from Morowitz’s deep thinking at the intersection of biology and physics, among them Stuart Kauffman, Chris Langton, Walter Fontana, Andreas Wagner, Steen Rasmussen, David Krakauer, Eric Smith, Rogier Braakman, and others.
“Harold’s books and his way of talking about science made him a voice to an enormous wider world that science was friendly,” says Smith. “This, I think, attracted a whole generation of young scientists to science and to biophysics.”
The Santa Fe Institute invites friends and colleagues of Harold Morowitz to share memories of his life and career in the comments below (moderated).
Read GMU President Angel Cabrera’s eulogy to Morowitz (March 29, 2016)
Read the obituary in Yale Daily News (April 11, 2016)