Science History Podcast

Due to recent technological advances, scientists have revolutionized our understanding of human evolutionary history. What appeared to be a relatively simple story of divergence from ancient hominids is instead a tangled mess involving repeated cycles of divergence and hybridization between evolving human species. Today my guest is Jason Wilder, who researches human evolutionary genetics and genomics. We discuss the genetics of malaria resistance and parallel evolution, CCR5 deficiency and resistance to HIV infection, gene editing and the creation of designer babies, gene editing to treat disease, and introgression between modern humans and archaic forms, including Neanderthals and Denisovans. Jason received his B.A. in biology at Williams College and his Ph.D. in Ecology and Evolutionary Biology at Princeton University. He then worked at the University of Arizona and Williams before joining the faculty at Northern Arizona University, where he is a professor of genetics and the Interim Dean of the College of the Environment, Forestry and Natural Sciences.

The brain is the most enigmatic of organs – it is really a collection of organs that undergoes a remarkable coordinated development that is driven in part by sex steroids. Today my guest is Margaret McCarthy, one of the leading researchers on sex differences in the brain. Here, we cover the history of research on sex and the brain, including the utility of animal models, the roles of hormones and sensitive periods in brain development, masculinization vs. feminization of the brain, epigenetic regulation of sex differences in the brain, differences between the sexes in the prevalence and age of onset of mental illnesses, and even the role of politics in the field of neurobiology. Margaret received her BS and MA degrees in biology at the University of Missouri in 1981 and 1984, respectively, and her PhD in behavioral neuroscience at Rutgers University in 1989. She then worked at Rockefeller University and the National Institutes of Health before joining the faculty at the University of Maryland, where she holds an endowed professorship and is the Chair of the Department of Pharmacology.

Today we explore the history of plutonium with Frank von Hippel, a retired but always active professor at Princeton University, where, in 1975, he co-founded Princeton’s Program on Science and Global Security in the Woodrow Wilson School of Public and International Affairs. In the 1980s, Frank was the chairman of the Federation of American Scientists, and in the Clinton Administration he was the Assistant Director for National Security in the White House Office of Science and Technology Policy. Frank has worked on nuclear arms control and nonproliferation since the 1980s, and received many awards for this work, including a MacArthur Fellowship. Frank received his B.S. in physics at MIT in 1959 and his Ph.D. in theoretical physics at the University of Oxford in 1962, where he was a Rhodes Scholar. Frank is also a co-author of the forthcoming book, “Plutonium: How nuclear power’s dream fuel became a nightmare.” We discuss the history of all things nuclear – the development of the bomb, the attacks on Hiroshima and Nagasaki, plutonium bomb accidents during the Cold War, breeder reactors, radioactive waste, trans-uranic elements and neutron capture, nuclear terrorism and dirty bombs, nuclear testing, nuclear energy, and the people involved.

We explore the history of the discovery of gravitational waves with Rai Weiss, including the relevance to special and general relativity, pulsars, supernovae, merging and binary black holes, space and time, neutron star collisions, dark matter, cosmic background radiation, gamma ray bursts, and even the viscosity of neutrinos. We also discuss really small numbers, the origin of the NSF and NASA, the LIGO scientific collaboration, the politics of science, and what all this has to do with Albert Einstein. Rai received his PhD at MIT in 1962, and taught at Tufts University and Princeton before returning to MIT. Among Rai’s many distinguished awards is the 2017 Nobel Prize in Physics, which he received along with Kip Thorne and Barry Barish “for decisive contributions to the LIGO detector and the observation of gravitational waves.”

In this supplemental episode with Matthew Meselson, I accepted his invitation to visit him in his office at Harvard, where we discussed yellow rain incidents in Southeast Asia. Meselson received his appointment as an Associate Professor of biology at Harvard in 1960 and his full professorship in 1964. He has been at Harvard ever since. Meselson has received many prominent awards throughout his career, including from the National Academy of Sciences, the Federation of American Scientists, the New York Academy of Sciences, and the Genetics Society of America, as well as the Guggenheim Fellowship and MacArthur Fellows Program Genius Award. 

Matthew Meselson organized the Herbicide Assessment Commission in 1970, which investigated the use of Agent Orange and other defoliants in Vietnam. The work of the commission helped to end Operation Ranch Hand, in which the United States sprayed nearly 20 million gallons – about 73 million liters - of herbicides and defoliants over the rainforest and mangrove forest canopies of Vietnam, Laos and Cambodia. I called Meselson to ask about his role in the Herbicide Assessment Commission, along with a host of other fascinating investigations to do with chemical and biological weapons, such as the anthrax accident in the Soviet Union and the yellow rain incident in Laos.  I also asked him about the U.S. Army’s insane plan in 1969 to ship 800 railroad cars filled with 27,000 tons of poison-gas weapons from the Rocky Mountain Arsenal to New Jersey for disposal at sea. Meselson completed his Ph.D. in 1957 under Linus Pauling at CalTech.  In 1958, in a classic experiment, he and Frank Stahl showed that DNA is replicated semi-conservatively, and in 1961 he along with Francois Jacob and Sydney Brenner discovered messenger RNA.  Meselson also made fundamental discoveries in DNA repair, the recognition and destruction of foreign DNA in cells, and, along with Werner Arber, he discovered restriction enzymes.  Meselson received his appointment as an Associate Professor of biology at Harvard in 1960 and his full professorship in 1964.  He has been at Harvard ever since.  Meselson has received many prominent awards throughout his career, including from the National Academy of Sciences, the Federation of American Scientists, the New York Academy of Sciences, and the Genetics Society of America, as well as the Guggenheim Fellowship and MacArthur Fellows Program Genius Award.

We live in a surreal and dangerous time – autocrats are on the rise and societies are regressing toward ethnic competition. Given this political moment, I decided to dedicate an episode of the podcast to the history of research on cooperation. My guest, Robert Axelrod, has been a professor of political science and public policy at the University of Michigan since 1974.  Prior to that, he was a professor at the University of California, Berkeley. He is a member of the U.S. National Academy of Sciences and a recipient of the MacArthur Foundation Fellowship, among many other awards. Pertinent to today’s episode, he received the 1990 National Academy of Sciences Award for Behavioral Research Relevant to the Prevention of Nuclear War. He also received the National Medal of Science from President Barack Obama. Axelrod is the author of seminal books in the field, such as The Evolution of Cooperation, published in 1984. In this episode, we discuss the famous computer competition on the prisoner’s dilemma that Axelrod ran in 1979, and the lessons learned regarding cooperation, altruistic behavior, kin selection, evolutionary stable strategies, and frequency dependent selection. The focus of our discussion is the winning strategy from the tournament, a strategy called tit for tat. We discuss modifications of tit for tat, including generosity and contrition to account for misunderstanding and misperception, and we discuss how this informs arms races and international relations. We also delve a bit into his interactions with Richard Dawkins, W.D. Hamilton, and E.O. Wilson, as well as his work related to cyberwarfare and cancer.

How did modern molecular biology become an integral component of forensic science? My guest, Bruce Budowle, played key roles in the development of genetic and microbial forensics, and he explains significant events in forensic science over the past four decades. Bruce joined the research unit of the FBI Laboratory Division in 1983 and rose in the ranks to become the Chief of the Forensic Science Research Unit and the Senior Scientist for the Laboratory Division. In 2009, Bruce left the FBI to become the Executive Director of the Institute of Applied Genomics at the University of North Texas Health Science Center. Bruce directs the Center for Human Identification and he is the Vice Chair of the Department of Microbiology, Immunology, and Genetics. He has published about 500 scientific articles and testified in over 250 criminal cases. Bruce and I discuss the missing children of Argentina’s Dirty War, the O.J. Simpson trial, the 9/11 terror attack on the World Trade Center, the subsequent anthrax letter attacks and the advent of microbial forensics, the DNA Fingerprinting Wars, DNA genealogies and forensics, and making mistakes in forensics.

Shortly after the al-Qaida terror attacks of September 11, 2001, a second wave of terror swept the United States – this time bioterrorism with anthrax mailed in letters as the weapon. Today my guest is Paul Keim, the scientist who conducted the genetic sleuthing and tracked down the source of the anthrax. Paul is the recipient of numerous scientific honors, and he is a professor of biological sciences at Northern Arizona University, where he directs the Pathogen and Microbiome Institute. In addition to the anthrax terror attacks, in today’s episode we discuss the Soviet and Iraqi anthrax weapons programs, the Haitian cholera outbreak sourced to Nepalese peacekeepers, virulent avian influenza, Scottish heroin addicts, and the Japanese doomsday cult Aum Shinrikyo.

One of the greatest mysteries in biology, until 1991, was how water moves across cell membranes. Today’s episode focuses on the history of the discovery of aquaporins, or proteins that act as water channels in cell membranes. My guest is Peter Agre, recipient of the 2003 Nobel Prize in Chemistry for his discovery of aquaporins. Among many other honors and leadership roles across his career, Peter became a member of the U.S. National Academy of Sciences in 2000 and served as President of the American Association for the Advancement of Science from 2009-2010. He is the Bloomberg Distinguished Professor in Molecular Microbiology and Immunology and in the School of Medicine at Johns Hopkins Bloomberg School of Public Health. Peter is also the Director of the Johns Hopkins Malaria Research Institute.