Big Biology

This is a free preview of a paid episode. To hear more, visit bigbiology.substack.comOn this episode, we take a break from the regular format to talk with Itai Yanai and Martin Lercher of The Night Science Podcast, a show that explores the creative side of science with guests from across the globe. Itai is a professor in the Department of Biochemistry and Molecular Pharmacology at the NYU School of Medicine, and Martin is a professor in both the Institute for Computer Science and the Department of Biology at Heinrich Heine University Düsseldorf. We had a great time chatting with them about our respective podcast experiences, trading tips and reflecting on our passion for science communication and the ways that it has impacted our own research.Cover art by Keating ShahmehriDonate to our spring fund drive! Or, become a patron! Or both! – hey, we’re not picky!

This is a free preview of a paid episode. To hear more, visit bigbiology.substack.comWhat is the “infinitesimal model”? How has our understanding of complex traits changed recently?On this episode, we talk with Nick Barton, an evolutionary quantitative geneticist at the Institute of Science and Technology Austria. Quantitative genetics has changed a lot in the past 30 years, driven by massive advances in DNA sequencing power and by new statistical and computational approaches to harnessing the data flood. Nick works at the forefront of the field, developing and testing new theory, and we discuss both his research and his perspectives on these changes. We end by asking Nick about his advice for early career researchers who want to navigate the complex landscape composed of theory, computation, and data.Cover art by Keating ShahmehriDonate to our spring fund drive! Or, become a patron! Or both! – hey, we’re not picky!

This is a free preview of a paid episode. To hear more, visit bigbiology.substack.comWhat is mutation bias? How does it affect evolution?In this episode, we talk with Arlin Stoltzfus, a research fellow at the University of Maryland’s Institute for Bioscience and Biotechnology Research. Arlin studies mutation bias – the idea that some types of mutations occur more often than others – and how these patterns can influence the evolutionary trajectories of populations. In the chat, we contrast this mutation-centric approach to evolution with more standard views in which selection does most of the creative heavy lifting. We center the talk around Arlin’s 2021 book - Mutation, Randomness, and Evolution, which offers a new conception of variation as a difference-maker in evolution. Looking forward, Arlin argues that a better understanding of mutation will make it easier to predict the origins and outcomes of different cancers and the evolution of infectious diseases and crop pests.Cover art by Keating Shahmehri

This is a free preview of a paid episode. To hear more, visit bigbiology.substack.comWhat are network motifs, and how and why do they matter to biological networks?On this episode, we talk with Uri Alon, systems biologist at the Weizmann Institute of Science, about biological networks. In the early 2000s, Uri discovered some of the fundamental characteristics of these networks and, since then, has worked to understand networks across different levels of biological organization. His work shows that, from genes to whole organisms, networks are filled with repeating patterns of connections known as network motifs, such as feedback and feedforward loops. We talk about how the motifs arise and what they mean for the performance and evolution of the systems in which they’re embedded. Moving farther afield, we also talk about how scientists can productively move into new areas, and how Uri teaches early-stage scientists to leap confidently into the unknown. And a bonus: Uri sings and plays guitar for us!Cover art: Keating Shahmehri

This is a free preview of a paid episode. To hear more, visit bigbiology.substack.comWhy do humans look so different from one another? Why do we have different types of hair and different skin colors? And what do these traits have to do with the concept of race?On this episode, we talk with Tina Lasisi, incoming professor at the University of Michigan, about variation in human hair structure and skin color. We talk about why such variation may have evolved, and how biologists are studying it. We also discuss the implications of her work for the concept of race. Tina encourages scientists and the public to be curious about (rather than afraid of) human diversity, as it’s an obvious part of our world that should be understood from multiple perspectives, including biological.Also be sure to check out the Preprints in Motion podcast here!Cover art by Keating Shahmehri

Happy holidays from the Big Biology team! As a bonus episode this week, we are sharing Art's recent interview with James Fodor on The Science of Everything podcast. Art and James discuss various topics in evolution and genetics, covering material that spans years of Big Bio conversations.Enjoy, and see you next year! This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit bigbiology.substack.com/subscribe

This is a free preview of a paid episode. To hear more, visit bigbiology.substack.comWhat’s the smallest number of genes that cells need to grow and reproduce? Is it possible to synthesize minimal genomes and insert them into cells? What do minimal genomes teach us about life?In this episode, we talk to John Glass, leader of the Synthetic Biology Group at the J. Craig Venter Institute. Over the past decade, Glass and colleagues developed techniques for manipulating and synthesizing entire bacterial genomes. Starting with Mycoplasma bacteria, which have very small genomes, they determined the minimal number of genes (473!) required to support life. They experimentally confirmed this number by synthesizing genomes from scratch, containing just the essential genes, and putting them into other bacteria whose genomes were removed. Cells in this lineage, called JCVI-syn3.0, grow and divide approximately like wildtype cells do.We talk with John about how they pulled it off and what this minimal genome tells us about life more generally. We also chat about the functions of essential genes and what so-called non-essential genes may do in the wild. Finally, we touch on what if anything minimal genomes say about the origin of life and on the group’s ongoing efforts to synthesize entire cells – not just genomes! – from scratch.Cover art by Keating Shahmehri

This is a free preview of a paid episode. To hear more, visit bigbiology.substack.comHow will we find life beyond Earth? Can we use a molecule's complexity to distinguish life from non-life?A common way to search for extraterrestrial life is to look for signs of complex organic molecules on other moons and planets. One trouble with this approach, though, is that lots of complex molecules can arise from inorganic processes. To be sure that complexity indicates life, we also need to distinguish forms of complexity that could only be produced by information-rich processes – things that must be alive.On today’s show, we talk with astrobiologist Sara Walker about this idea in relation to a new theory, called assembly theory, that she and colleagues are currently developing. Assembly theory characterizes the complexity of objects, including molecules, by how many steps are required to make them – the more steps, the higher the object’s complexity index. This perspective reorients our attention from the traits of objects that make them complex to the historical sequence of events that must have occurred to create them. Sara proposes that this idea provides natural ways to think about a large set of interesting processes, including how information is manifest and used in living systems, the creative roles of natural selection in evolution, and the ever present problem of understanding levels of selection.This was Sara’s second appearance on the show, check out her first episode here.Cover art by Keating Shahmehri

This is a free preview of a paid episode. To hear more, visit bigbiology.substack.comWhat hidden life lies at the bottom of the deep ocean? How do so many species survive and even thrive with so little light and food and at such pressure?In this episode, we talk to Helen Scales, a marine biologist, writer, and broadcaster who has written the essential guidebook to the deep ocean titled “The Brilliant Abyss”. On our way to the bottom of the sea, Helen recounted her journey from academia to writing and shared some of the lessons for others looking to dive into science communication. She also introduced us to some of her favorite species and their unique adaptations for surviving at extreme depths as well as several threats that the deep ocean faces. Technology has not only opened up this ecosystem to exploration but also to exploitation. Helen lays out the current state of ocean conservation and offers some hope and advice to those looking to protect the planet's largest habitat.Cover art: Keating Shahmehri

This is a free preview of a paid episode. To hear more, visit bigbiology.substack.comWhat is eco-evo-devo? How can ants help us understand the evolution of development?There are 20 quadrillion ants in the world, and they come in lots of different shapes and sizes. We even see big differences within colonies, like ants in the genus Pheidole which have different castes: workers, soldiers, and, in some species, super soldiers. Super soldiers are the muscle-y brutes of the ant world that grow huge heads to defend the colony and attack large food items, like other insects. This variation is all due to developmental plasticity – the same ant genotype produces distinct phenotypes depending on the environment of their early lives.On this episode, we talk with Rajee Rajakumar, a professor at the University of Ottawa, who studies Pheidole ants to understand the interactions between their genes, their developmental environments, and their phenotypes. Rajee is also a HUGE ant fan! We talk with him about his 2018 paper in Nature about the mysterious organs that control these differences in development, and amazingly, how these organs could be socially regulated via pheromones.Cover art: Keating Shahmehri