Everyone loves a good evolutionary puzzle. Why do we have appendices? Why do we dream? Why do we blush? At first glance, memory would not seem to be in this category. It's clearly useful to remember stuff, after all—to know where to find food, to remember your mistakes so you don't repeat them, to recall who's friendly and who's fierce. In fact, though, certain aspects of memory—when you hold them up to the light—turn out to be quite puzzling indeed.

My guests today are Dr. Ali Boyle and Dr. Johannes Mahr. Ali is a philosopher at the London School of Economics (LSE); Johannes is a philosopher at York University, in Toronto. Both have written extensively about the functions of memory, and, in particular, about the functions of episodic memory—that capacity for calling up specific events and experiences from our own lives.

Here, Ali, Johannes and I lay out the textbook taxonomy of memory, and discuss how episodic memory has drawn the lion's share of philosophical interest. We pick apart the relationship between episodic memory and another major type of long-term memory, semantic memory. We sketch a range of different accounts of the evolved functions of episodic memory, including Johannes's proposal that episodic memory serves communication and Ali's proposal that it fuels semantic memory. And, finally, we consider what this all means for our understanding of memory in children and in animals. Along the way, we touch on Highly Superior Autobiographical Memory, infantile amnesia, evidential systems in language, imagination, "simulationist" theories of episodic memory, what it feels like to remember, collective memory, the hippocampus, cryptomnesia, and the cow's digestive system as a metaphor for memory.

If you're enjoying Many Minds, you might consider leaving us a rating or review on your platform of choice, or maybe giving us a shout-out on social media. Thanks so much in advance for supporting us, friends!

Notes

4:30 – For a broad orientation to memory research in the cognitive sciences, see here. For a broad orientation to the philosophy of memory, see here.

13:00 – See here for Dr. Boyle's paper on the "impure phenomenology" of episodic memory.

16:30 – For more on the idea of "WEIRD"-ness and the "WEIRD problem" in psychology, see our previous audio essay and our recent episode on childhood across cultures.

20:00 – For more on metaphors for memory in the cognitive sciences, see here (in which an apparently different "cow stomach" metaphor for memory is discussed). Note that cows do not, in fact, have four stomachs, but rather a single stomach with four distinct chambers.

24:00 – For an overview of the cognitive neuroscience of episodic memory, see here.

31:30 – For a discussion of the commonsense "mnemonic view" of episodic memory, see Dr. Boyle's recent article.

37:00 – For one influential articulation of a "simulationist" account of episodic memory, see here.

40:00 – For the proposal by Dr. Mahr and his colleague that episodic memory is for communication, see here and here.

45:00 – For more on evidential systems in language, see here and here.

48:00 – For the study by Dr. Mahr and colleagues on source memory in children, see here.

51:30 ­– For Dr. Boyle's proposal that episodic memory is for semantic memory, see here. For another of Dr. Boyle's discussions of the functions of episodic memory, see here.

1:02:00 – For more of Dr. Mahr's ideas about the cultural evolution of the "epistemic tag" that distinguishes episodic memory, see here.

1:03:00 – Partially digested stomach contents are sometimes known as "chyme."

1:07:00 – A news story about recent findings on infantile amnesia.

1:08:00 – A recent review article about Highly Superior Autobiographical Memory.

1:12:00 – An empirical study on the phenomenology of "cryptomnesia."

1:15:00 – For a recent discussion of episodic memory in animals, see this paper by Dr. Boyle and a colleague. Examples of Dr. Boyle's other work on memory in animals are here and here.

Recommendations

The Memory Palace (blog)

The Invention of Tomorrow, by Thomas Suddendorf, Jonathan Redshaw, & Adam Bulley (see also our episode featuring this book)

Searching for Memory, by Daniel Schacter

The Enigma of Reason, by Hugo Mercier & Dan Sperber

Many Minds is a project of the Diverse Intelligences Summer Institute, which is made possible by a generous grant from the John Templeton Foundation to Indiana University. The show is hosted and produced by Kensy Cooperrider, with help from Assistant Producer Urte Laukaityte and with creative support from DISI Directors Erica Cartmill and Jacob Foster. Our artwork is by Ben Oldroyd.

Subscribe to Many Minds on Apple, Stitcher, Spotify, Pocket Casts, Google Play, or wherever you listen to podcasts. You can also now subscribe to the Many Minds newsletter here!

We welcome your comments, questions, and suggestions. Feel free to email us at: [email protected].

For updates about the show, visit our website or follow us on Bluesky (@manymindspod.bsky.social).

It's hard to say exactly when, but some tens of thousands of years ago, our best friends were born. I'm referring, of course, to dogs. This didn't happen overnight—it was a long process. And it not only changed how those canids behaved and what they looked like, it also changed their brains. As wolves gave way to proto-dogs, and proto-dogs gave way to dingoes and dalmatians and Dobermanns and all the rest, their brains have continued to change. What can we learn from this singular saga? What does it tell us about dogs, about domestication, and about brains?

My guest today is Dr. Erin Hecht. Erin is an Assistant Professor in the Department of Human Evolutionary Biology at Harvard, where she directs the Canine Brains Project.

Here Erin and I talk about how dogs are the most anatomically diverse species on the planet—and how their brains are no exception. We sketch the different waves in the dog domestication saga and discuss scenarios for how that saga got underway. We talk about how brains change as they get bigger and about how they change during domestication. We discuss a recent study by Erin and colleagues comparing the brains of modern dogs with the brains of pre-modern dogs like village dogs and New Guinea singing dogs. We also talk about a new study from Erin's lab finding that domestic dogs share with humans a key language-related structure. Along the way we talk about the Russian Farm Fox experiment, the stereotype of the gentle giant, the left lateralization of language, the respiratory condition known as BOAS, the dog personality inventory known as C-BARQ, the limitations of the idea of a "domestication syndrome," and the puppy kidnapping hypothesis.

Longtime listeners will recall that we had Erin on the show to talk about her work on fermentation and brain evolution. Given how much fun we had with that one, it was only a matter of time before we had her back to talk about her main line of research on dog brains. So here you go friends—hope you enjoy it!

Notes

4:30 – For one recent study of the early domestication of dogs, see here. For a review of leading hypotheses about what drove the wolf-to-dog transition, see here.

13:00 – For Dr. Hecht's initial 2019 study of brain variation across domestic dog breeds, see here.

20:00 – For a classic paper on the neurodevelopmental scaling by Dr. Barbara Finlay and colleagues, see here.

23:00 – For more of Dr. Hecht's work on neurodevelopmental scaling laws as they apply to dogs, see here. For a study reporting correlations between body size and personality in dogs, see here.

29:00 – See Dr. Hecht and colleagues' recent paper on the evolutionary neuroscience of domestication.

31:00 – See Dr. Hecht and colleagues' recent paper on brain changes seen in the Russian farm-fox experiment.

37:00 – For more on the idea of "domestication syndrome," see our recent episode with Dr. Kevin Lala and this critical discussion. For a classic treatment of the idea that domestication involves reduction in brain size, see here.

41:00 – For the recent study by Dr. Hecht and colleagues comparing the brains of modern and pre-modern dog breeds, see here.

43:00 – For video of a New Guinea Singing Dog singing, see here.

47:00 – For more about the dog personality inventory known as the C-BARQ, see here.

51:00 – For Dr. Hecht and colleagues' recent study on an analog to the "arcuate fasciculus" in dogs, see here.

58:00 – For Dr. Hecht and colleagues' study on arcuate fasciculus in chimpanzees (and its relationship to communicative behavior), see here. For more discussion of the hemispheric lateralization of language, see our recent interview with Dr. Ev Federenko.

1:04:00 – The website of the Functional Dog Collaborative.

Recommendations

Dogs: A New Understanding of Canine Origin, Behavior and Evolution, Raymond & Lorna Coppinger

Evolving Brains, John Allman

It seems we've always had monsters among us. We've long been enthralled by dragons and giants, by the likes of Frankenstein and Godzilla and Dracula, by witches and werewolves and countless others. They roam our maps and creation myths; they crop up in our dreams, in our children's books, in our political rhetoric. Where do these beings spring from? What do they do for us? How have they changed over time? And, ultimately, what do our monsters say about their makers?

My guests today are Dr. Natalie Lawrence and Dr. Surekha Davies. Both are historians of science and authors of recent books on monsters: Natalie's book is Enchanted creatures: Our monsters and their meanings. Surekha's book is Humans: A monstrous history.

Here, Surekha, Natalie, and I talk about monsters as category breakers and boundary walkers—and about how monstrosity is in the eye of the beholder. We walk through a menagerie of monsters—from the apocryphal blemmyes of old travelogues, to a hairy-faced girl in 16th century France, to the figure of Caliban in The Tempest. We discuss the psychological and cultural forces that generate monsters. And we talk about whether anyone would want to live in a world without them.

Along the way, we touch on the "monstrification" of social groups; psychoanalysis; our primal fear of snakes; curiosity cabinets; therianthropes and the Cave of the Three Brothers; the relationship between monstrosity and geography; our long fascination with so-called monstrous births; the Muppet Show; dinosaurs and sea creatures; and the question of what monsters might do for children in particular.

Alright friends, it's the monstrous season and this is a fun one to help you celebrate. Enjoy!

Notes

3:00 – Grendel's mother has often been a subject of critical discussion and adaptation. See, for instance, the 2018 novel, The Mere Wife.

12:30 – For a classic history-of-science treatment of "wonders" (including monsters) and our conceptions of nature, see here.

18:30 – For those unfamiliar with muppets, an episode of the Muppet Show, which premiered in 1976.

24:00 – The blemmyes were often the subjects of illustration—for examples, see here.

26:00 – For more on Sir Walter Raleigh and the blemmyes, see Dr. Davies' recent newsletter post.

29:00 – One example of monsters at the margins of maps can be seen in the Psalter World Map.

32:00 – For more on Cave of the Trois-Frères and the Sorcerer, see here.

34:00 – For more on shamanism, see our recent episode with Manvir Singh.

37:00 – Therianthropes are relatively rare in cave art, but have nonetheless been widely discussed. For an example, see here.

39:00 – For more on Antonietta Gonsalvus and her family, including examples of how she was represented in paintings of the era, see here.

45:00 – The trope of monsters in creation stories is often called "chaoskampf."

47:00 – The meanings of Medusa have been widely discussed and debated. See here for an example.

52:00 – For more about Caliban, and the racial and colonial dimensions of the Tempest, see here.

57:00 – The Steinbeck quote comes from his book, The Log from 'The Sea of Cortez.'

Recommendations

The Ashgate Research Companion to Monsters and the Monstrous, edited by Asa Simon Mittman & Peter J. Dendle

Spectacle of Deformity, by Nadja Durbach

The Modern Myths, by Philip Ball

The Monsters and the Critics (and other essays), by J.R.R. Tolkien

No Go the Bogeyman, by Marina Warner

Where the Wild Things Are, by Maurice Sendak

Many Minds is a project of the Diverse Intelligences Summer Institute, which is made possible by a generous grant from the John Templeton Foundation to Indiana University. The show is hosted and produced by Kensy Cooperrider, with help from Assistant Producer Urte Laukaityte and with creative support from DISI Directors Erica Cartmill and Jacob Foster. Our artwork is by Ben Oldroyd.

Subscribe to Many Minds on Apple, Stitcher, Spotify, Pocket Casts, Google Play, or wherever you listen to podcasts. You can also now subscribe to the Many Minds newsletter here!

We welcome your comments, questions, and suggestions. Feel free to email us at: [email protected].

For updates about the show, visit our website or follow us on Bluesky (@manymindspod.bsky.social).

AI therapists and caregivers. Digital tutors and advisors and friends. Artificial lovers. Griefbots trained to imitate dead loved ones. Welcome, to the bustling world of AI-powered chatbots. This was once the stuff of science fiction, but it's becoming just the stuff of everyday life. What will these systems do to our society, to our relationships, to our social skills and motivations? Are these bots destined to leave us hollowed out, socially stunted, screen-addicted, and wary of good-old-fashioned, in-the-flesh human interaction? Or could they actually be harnessed for good?

My guest today is Dr. Henry Shevlin. Henry is a philosopher and AI ethicist at the Leverhulme Centre for the Future of Intelligence (CFI) at Cambridge University. In a series of recent papers, Henry has been exploring this brave new world of "social AI" and its philosophical, ethical, and psychological dimensions.

Here, Henry and I sketch the current landscape of social AI—from dedicated platforms like Replika and CharacterAI to the more subtly social uses of ChatGPT and Claude. We consider several tragic cases that have recently rocketed these kinds of services into public awareness. We talk about what's changed about AI systems—quite recently—that's now made them capable of sustained relationships. We linger on the possible risks of social AI and, perhaps less obviously, on the possible benefits. And we consider the prospects for regulation. Along the way, Henry and I also talk about his 81-year-old father, his teenage self, and, of course, the kids these days; we consider whether social AI, in its potential harms, is more like social media or more like violent video games; we talk about "deskilling" and it's opposite "upskilling"; and we of course take stock of a certain elephant in the room.

Alright friends, this is a fun one. We've been wanting to explore this dawning age of social AI for some time. And we finally found, in Henry, the right person to do it with. Enjoy!

Notes

3:00 – The piece in The Guardian—'It's time to prepare for AI personhood'—by Jacy Reece Anthis.

5:00 – The Replika subreddit.

9:30 – News coverage of recent research on the bedside manner of AI systems.

10:30 – For a recent paper on AI by the philosopher Ophelia Deroy, see here.

11:30 – For some of Dr. Shevlin's recent writing about "social AI", see here and here.

13:30 – OpenAI's recent report, 'How People Use ChatGPT'.

16:30 – For examples of popular media coverage of recent (tragic) cases involving chatbots, see here, here, here, and here.

21:00 – The paper by Rose Guingrich and Michael Graziano on how users describe their relationships with chatbots.

24:00 – The precise quote by Mark Twain is: "Nothing so needs reforming as other people's habits."

25:30 – The classic paper on Mary's room by Frank Jackson.

27:00 – Dr. Shevlin has also worked on questions about animal minds (e.g., here), as well as a number of issues in AI beyond "social AI" (e.g., here, here).

30:00 – The classic essay by Isaiah Berlin on hedgehogs and foxes.

32:00 – The classic paper on ELIZA, introduced by Joseph Weizenbaum in 1966. A version of ELIZA that you can interact with. For work by Sherry Turkle, see here.

34:00 – Dr. Shevlin's recent paper about the "anthropomimetic turn" in contemporary AI.

41:00 – For recent work on whether current chatbots pass a version of the Turing test, see here.

45:00 – Ted Chiang's story, 'The Lifecycle of Software Objects,' was re-published as part his collection of short fiction, Exhalation.

46:00 – For Dr. Shevlin's recent writing on machine consciousness, see here.

48:00 – For more on the possibility of consciousness in borderline cases (like AI systems), see our past episodes here and here.

52:00 – The study on whether people attribute consciousness to LLMs.

54:30 – A recent paper on griefbots by scholars at the University of Cambridge. A popular article about the phenomenon.

55:30 – A blogpost describing the so-called DigiDan experiment.

1:00:00 – Some of the potentially positive social qualities of AIs are discussed in this essay by Paul Bloom.

1:19:30 – For more on Iain Banks' culture series, see here.

1:20:30 – A popular article on the phenomenon of hikikomori.

Recommendations

The Oxford Intersections: AI in Society collection

The new podcast, Our Lives with Bots

Many Minds is a project of the Diverse Intelligences Summer Institute, which is made possible by a generous grant from the John Templeton Foundation to Indiana University. The show is hosted and produced by Kensy Cooperrider, with help from Assistant Producer Urte Laukaityte and with creative support from DISI Directors Erica Cartmill and Jacob Foster. Our artwork is by Ben Oldroyd.

Subscribe to Many Minds on Apple, Stitcher, Spotify, Pocket Casts, Google Play, or wherever you listen to podcasts. You can also now subscribe to the Many Minds newsletter here!

We welcome your comments, questions, and suggestions. Feel free to email us at: [email protected].

For updates about the show, visit our website or follow us on Bluesky (@manymindspod.bsky.social).

Birds do the darnedest things. They fly, of course. They sing. They hunt in pitch darkness. They hide their food and remember where they put it. They use tools and migrate over astonishingly vast distances—sometimes even sleeping while in flight. How do they do all this? What's going on in their brains that makes these and other remarkable behaviors possible? How did their evolutionary path mold them into the incredible creatures they are today?

My guests today are Dr. Andrew Iwaniuk and Dr. Georg Striedter. Andrew is a comparative neuroscientist and Associate Professor at the University of Lethbridge in Canada. Georg is a Professor of Neurobiology and Behavior at the University of California, Irvine. Together they are the authors of the new book, Bird Brains and Behavior: A Synthesis (available open access here).

Here, Georg, Andrew, and I consider the deep history of birds—how they skirted the mass extinction event that felled the dinosaurs, and then radiated out into the 11,000 plus species we know today. We talk about how bird brains differ from those of mammals and reptiles—in terms of their size, but also in terms of their major structures, and in terms of their wrinkliness. We tour some of the most peculiar and perplexing bird behaviors, and consider their neural and anatomical underpinnings. Finally, we consider what we can learn from bird brains, not just about birds but about brains in general—how they evolve, how they get wired up, how they do and do not vary. Along the way we touch on barn owls, hummingbirds, megapodes, mallards, pigeons, parrots, starlings, and underestimated waterfowl; we touch on how birds' brains change with the seasons; the enduring mystery of magnetoreception; the possibility of olfactory maps; the optocollic reflex; the social intelligence hypothesis and the extractive foraging hypothesis; precocial versus altricial bird species; split-body gynandromorphy; and the future of non-invasive work in bird neuroscience.

Season 7 of Many Minds is now gathering steam. We've got some great episodes in the works for you. Just a little reminder that we'd be grateful—thrilled, even—if you could help us get the word out about our show. You might do this by leaving a rating or a review, or by telling a colleague about us. We really appreciate the support, friends!

Without further ado, here's my conversation with Dr. Georg Striedter and Dr. Andrew Iwaniuk. Enjoy!

Notes

8:00 – For more on the deep history of the brains of birds and other vertebrates, see: Dr. Striedter's book (co-authored with R. Glenn Northcutt), Brains Through Time; this paper authored by Dr. Striedter and colleagues; and this paper authored by Dr. Iwaniuk and colleagues.

9:30 – The paper on neuron density in birds, by Dr. Pavel Němec and colleagues.

20:00 – For more about Dr. Striedter and colleagues revising some of the terminology for bird brain structures, see here and here.

24:00 – A paper by Dr. Striedter and colleagues on cortical folding.

34:00 – A recent paper describing seasonal neurogenesis in European starlings.

38:00 – A paper on the phenomenon of unihemispheric sleep across species.

42:00 – A video demonstrating the optocollic reflex in a bird.

45:00 – A paper on the puzzles of magnetoreception in birds and other animals.

51:00 – A classic paper on sound localization in barn owls.

54:00 – A paper by Dr. Iwaniuk and colleagues showing that harriers have an auditory system much like the (better-studied) owl.

58:00 – For more on place cells, the hippocampus, and cognitive maps, see our previous episode with Dr. Hugo Spiers. For more on the evolution of the hippocampus in birds and reptiles, see Dr. Striedter's paper here.

1:02:00 – For images of gynandromorphy in birds, see here and here.

1:10:00 – For a recent paper on "parental provisioning," the precocial-altricial spectrum, and brain size in birds, see here.

1:13:00 – For examples of research on the social intelligence hypothesis in birds and other animals, see here and here.

1:18:00 – For work by Dr. Iwaniuk and colleagues on some of the most interesting features of parrot brains, see here.

1:27:00 – The Avonet database.

Recommendations

Flight Paths, by Rebecca Heisman

An Immense World, by Ed Yong [former guest!]

Mind of the Raven, by Bernd Heinrich

Bird Brain, by Nathan Emery

Soul Made Flesh, by Carl Zimmer

Many Minds is a project of the Diverse Intelligences Summer Institute, which is made possible by a generous grant from the John Templeton Foundation to Indiana University. The show is hosted and produced by Kensy Cooperrider, with help from Assistant Producer Urte Laukaityte and with creative support from DISI Directors Erica Cartmill and Jacob Foster. Our artwork is by Ben Oldroyd.

Subscribe to Many Minds on Apple, Stitcher, Spotify, Pocket Casts, Google Play, or wherever you listen to podcasts. You can also now subscribe to the Many Minds newsletter here!

We welcome your comments, questions, and suggestions. Feel free to email us at: [email protected].

For updates about the show, visit our website or follow us on Bluesky (@manymindspod.bsky.social).

One afternoon you decide to snub your responsibilities and go for a hike. You spend a few hours in the woods or the mountains. You study the bark of trees, you bathe in birdsong, you let your eyes roam along a distant ridgeline. And you come back feeling better, restored somehow—like you have more energy, more patience, more bandwidth. We've all, I'm guessing, had experiences like this. But what's behind these effects? Why would nature restore us? What's the evidence that it really does? And what is even being restored, actually?

My guest today is Dr. Marc Berman. Marc is an Associate Professor in the Department of Psychology at the University of Chicago where he directs the Environmental Neuroscience Lab. Marc is also the author of a new book, Nature and the Mind: The Science of How Nature Improves Cognitive, Physical, and Social Well-Being.

Here, Marc and I talk about Attention Restoration Theory—the idea that nature experiences restore our limited capacity for directed attention. We discuss the broader field of "environmental neuroscience," which Marc helped kickstart and continues to lead. We range across studies from Marc's lab that show nature's beneficial effects—on attention, on mood, and on health. We talk about what the active ingredients in nature seem to be. And we discuss the field's prospects for understanding how nature impacts not just the mind, but the brain itself. Along the way, Marc and I touch on: soft versus harsh fascination; the elusive concept of "mental energy"; trees, wood, fire, and rain; the architect and theorist Christopher Alexander; the value of fake plants; fractalness in space and time; curvature and spirituality; and how nature tends to steer our thoughts in certain directions.

Needless to say, we're stoked to be kicking off a new season of Many Minds. If you're new to the show, welcome! If you're already a fan, perhaps you'd consider leaving us a rating or a review on your platform of choice. It really does help us reach new listeners.

Alright friends, on to my conversation w/ Dr. Marc Berman. Enjoy!

Notes and links

7:00 – For more on Attention Restoration Theory and the distinctions it makes between directed attention and involuntary attention, see this paper by Dr. Stephen Kaplan. For more on the construct of "directed attention" in general, see this paper by Dr. Kaplan and Dr. Berman.

12:00 – For an overview of the aims and scope of "environmental neuroscience," see this paper by Dr. Berman and colleagues.

17:00 – The 1989 book by Dr. Stephen Kaplan and Dr. Rachel Kaplan, The Experience of Nature

21:30 – For the "walk in the park" study that kickstarted Dr. Berman's research on environmental neuroscience, see here.

25:30 – For some of Dr. Berman and colleagues' work on nature sounds, see here and here.

27:00 – For a study on the possible benefits of nature for children with ADHD, see here.

30:00 – For more on the Garden of the Phoenix (aka the Osaka Garden) in Chicago, see here. For a news article about the benefits of "tiny forests," see here.

34:00 – See here for the follow-up to the "walk in the park" study with people experiencing depression.

38:00 – For the study on the relationship between tree cover and cardiometabolic health in Toronto, see here.

44:00 – For the classic study by Dr. Roger Ulrich on how the view from one's hospital room may impact recovery, see here.

47:00 – For more on the link between crime and nature in apartment complexes in Chicago, see here.

49:00 – A preprint by Dr. Berman and colleagues on the "compressibility" and memorability of natural images is here.

55:00 – For some of Dr. Berman's earliest work on the "low-level" visual features of natural scenes, see here.

57:00 – For the work, led by Kathryn Schertz, on how natural (or non-natural) images with curved edges direct our thoughts, see here.

1:01:00 – The firelight talk paper is here.

1:02:30 – For the study by Dr. Schertz, Dr. Berman, and colleagues comparing thoughts in the conservatory and at the mall, see here.

1:05:00 – For the study on a historical increase in the use of the generic term "tree" in English, see here.

1:06:00 – Christopher Alexander, the architect and theorist, is perhaps best known for his (co-authored) book, A Pattern Language. For the study by Alex Coburn, Dr. Berman, and colleagues, see here.

1:09:30 – To get a visual flavor of La Sagrada Familia, see here.

1:18:00 – The study on whether people can reliably predict how much they will enjoy a walk in nature.

1:20:00 – For some of Dr. Berman and colleagues' initial work on temporal "fractalness" in the brain, see here.

Recommendations

Greg Bratman et al., 'Nature and human well-being: The olfactory pathway'

Kim Doell et al., 'Leveraging neuroscience for climate change research'

Lucia Mason et al., 'Short-term exposure to nature and benefits for students' cognitive performance: A review'

Many Minds is a project of the Diverse Intelligences Summer Institute, which is made possible by a generous grant from the John Templeton Foundation to Indiana University. The show is hosted and produced by Kensy Cooperrider, with help from Assistant Producer Urte Laukaityte and with creative support from DISI Directors Erica Cartmill and Jacob Foster. Our artwork is by Ben Oldroyd.

Subscribe to Many Minds on Apple, Stitcher, Spotify, Pocket Casts, Google Play, or wherever you listen to podcasts. You can also now subscribe to the Many Minds newsletter here!

We welcome your comments, questions, and suggestions. Feel free to email us at: [email protected].

For updates about the show, visit our website or follow us on Bluesky (@manymindspod.bsky.social).

Hi friends!

We're taking a much-needed summer pause—we'll have new episodes for you later in September. In the meanwhile, enjoy this pick from our archives!

-------

[originally aired June 1, 2023]

There's a common story about the human past that goes something like this. For a few hundred thousand years during the Stone Age we were kind of limping along as a species, in a bit of a cognitive rut, let's say. But then, quite suddenly, around 30 or 40 thousand years ago in Europe, we really started to come into our own. All of a sudden we became masters of art and ornament, of symbolism and abstract thinking. This story of a kind of "cognitive revolution" in the Upper Paleolithic has been a mainstay of popular discourse for decades. I'm guessing you're familiar with it. It's been discussed in influential books by Jared Diamond and Yuval Harari; you can read about it on Wikipedia. What you may not know is that this story, compelling as it may be, is almost certainly wrong.

My first guest today is Dr. Eleanor Scerri, an archaeologist at the Max Planck Institute for the Science of Human History, where she heads the Pan-African Evolution research group. My second guest is Dr. Manuel Will, an archaeologist and Lecturer at the University of Tübingen in Germany. Together, Eleanor and Manuel are authors of a new paper titled 'The revolution that still isn't: The origins of behavioral complexity in Homo sapiens.' In the paper, they pull together a wealth of evidence showing that there really was no cognitive revolution—no one watershed moment in time and space. Rather, the origins of modern human cognition and culture are to be found not in one part of Europe but across Africa. And they're also to be found much earlier than that classic picture suggests.

Here, we talk about the "cognitive revolution" model and why it has endured. We discuss a seminal paper from the year 2000 that first influentially challenged the revolution model. We talk about the latest evidence of complex cognition from the Middle Stone Age in Africa—including the perforation of marine shells to make necklaces; and the use of ochre for engraving, painting, and even sunblock. We discuss how, though the same complex cognitive abilities were likely in place for the last few hundred thousand years, those abilities were often expressed patchily in different parts of the world at different times. And we consider the factors that led to this patchy expression, especially changes in population size.

I confess I was always a bit taken with this whole "cognitive revolution" idea. It had a certain mystery and allure. This new picture that's taking its place is certainly a bit messier, but no less fascinating. And, more importantly, it's truer to the complexities of the human saga.

Alright friends, on to my conversation with Eleanor Scerri & Manuel Will. Enjoy!

A transcript of this episode is available here.

Notes and links

3:30 – The paper by Dr. Scerri and Dr. Will we discuss in this episode is here. Their paper updates and pays tribute to a classic paper by McBrearty and Brooks, published in 2000.

6:00 – The classic "cognitive revolution" model sometimes discussed under the banner of "behavioral modernity" or the "Great Leap Forward." It has been recently featured, for instance, in Harari's Sapiens.

11:00 – Dr. Scerri has written extensively on debates about where humans evolved within Africa—see, e.g., this paper.

18:00 – A study of perforated marine shells in North Africa during the Middle Stone Age. A paper by Dr. Will and colleagues about the use of various marine resources during this period.

23:00 – A paper describing the uses of ochre across Africa during the Middle Stone Age. Another paper describing evidence for ochre processing 100,000 years ago at Blombos Cave in South Africa. At the same site, engraved pieces of ochre have been found.

27:00 – A study examining the evidence that ochre was used as an adhesive.

30:00 – For a recent review of the concept of "cumulative culture," see here. We discussed the concept of "cumulative culture" in our earlier episode with Dr. Cristine Legare.

37:00 – For an overview of the career of the human brain and the timing of various changes, see our earlier episode with Dr. Jeremy DeSilva.

38:00 – An influential study on the role of demography in the emergence of complex human behavior.

41:00 – On the idea that distinctive human intelligence is due in large part to culture and our abilities to acquire cultural knowledge, see Henrich's The Secret of Our Success. See also our earlier episode with Dr. Michael Muthukrishna.

45:00 – For discussion of the Neanderthals and why they may have died out, see our earlier episode with Dr. Rebecca Wragg Sykes.

Recommendations

Dr. Scerri recommends research on the oldest Homo sapiens fossils, found in Morocco and described here, and new research on the evidence for the widespread burning of landscapes in Malawi, described here.

Dr. Will recommends the forthcoming update of Peter Mitchell's book, The Archaeology of Southern Africa.

See Twitter for more updates from Dr. Scerri and Dr. Will.

Many Minds is a project of the Diverse Intelligences Summer Institute, which is made possible by a generous grant from the John Templeton Foundation to Indiana University. The show is hosted and produced by Kensy Cooperrider, with help from Assistant Producer Urte Laukaityte and with creative support from DISI Directors Erica Cartmill and Jacob Foster. Our artwork is by Ben Oldroyd. Our transcripts are created by Sarah Dopierala.

Subscribe to Many Minds on Apple, Stitcher, Spotify, Pocket Casts, Google Play, or wherever you listen to podcasts. You can also now subscribe to the Many Minds newsletter here!

We welcome your comments, questions, and suggestions. Feel free to email us at: [email protected].

For updates about the show, visit our website or follow us on Twitter (@ManyMindsPod) or Bluesky (@manymindspod.bsky.social).

Hi friends!

We're taking a much-needed August pause—we'll have new episodes for you in September. In the meanwhile, enjoy this pick from our archives!

_____

[originally aired February 8, 2024]

Where do memories live in the brain? If you've ever taken a neuroscience class, you probably learned that they're stored in our synapses, in the connections between our neurons. The basic idea is that, whenever we have an experience, the neurons involved fire together in time, and the synaptic connections between them get stronger. In this way, our memories for those experiences become minutely etched into our brains. This is what might be called the synaptic view of memory—it's the story you'll find in textbooks, and it's often treated as settled fact. But some reject this account entirely. The real storehouses of memory, they argue, lie elsewhere.

My guest today is Dr. Sam Gershman. Sam is Professor of Psychology at Harvard University, and the director of the Computational Cognitive Neuroscience Lab there. In a recent paper, he marshals a wide-ranging critique of the synaptic view. He makes a compelling case that synapses can't be the whole story—that we also have to look inside the neurons themselves.

Here, Sam and I first discuss the synaptic view and the evidence that seems to support it. We then talk about some of the problems with this classic picture. We consider, for example, cases where memories survive the radical destruction of synapses; and, more provocatively, cases where memories are formed in single-celled organisms that lack synapses altogether. We talk about the dissenting view, long lurking in the margins, that intracellular molecules like RNA could be the real storage sites of memory. Finally, we talk about Sam's new account—a synthesis that posits a role for both synapses and molecules. Along the way we touch on planaria and paramecia; spike-timing dependent plasticity; the patient H.M.; metamorphosis, hibernation, and memory transfer; the pioneering work of Beatrice Gelber; unfairly maligned ideas; and much, much more.

Before we get to it, one important announcement: Applications are now open for the 2024 Diverse Intelligences Summer Institute (or DISI)! The event will be held in beautiful, seaside St Andrews, Scotland, from June 30 to July 20. If you like this show—if you like the conversations we have and the questions we ask—it's a safe bet that you'd like DISI. You can find more info at disi.org—that's disi.org. Review of applications will begin on Mar 1, so don't delay.

Alright friends, on to my conversation about the biological basis of memory with Dr. Sam Gershman. Enjoy!

Notes and links

4:00 - A general audience article on planarian memory transfer experiments and the scientist who conducted them, James V. McConnell.

8:00 - For more on Dr. Gershman's research and general approach, see his recent book and the publications on his lab website.

9:30 - A brief video explaining long-term potentiation. An overview of "Hebbian Learning." The phrase "neurons that fire together wire together" was, contrary to widespread misattribution, coined by Dr. Carla Shatz here.

12:30 - The webpage of Dr. Jeremy Gunawardena, Associate Professor of Systems Biology at Harvard University. A recent paper from Dr. Gunawardena's lab on the avoidance behaviors exhibited by the single-celled organism Stentor (which vindicates some disputed, century-old findings).

14:00 - A recent paper by C. R. Gallistel describing some of his views on the biological basis of memory.

19:00 - The term "engram" refers to the physical trace of a memory. See recent reviews about the so-called search for the engram here, here, and here.

20:00 - An article on the importance of H.M. in neuroscience.

28:00 - A review about the phenomenon of spike-timing dependent plasticity.

33:00 - An article, co-authored by former guest Dr. Michael Levin, on the evidence for memory persistence despite radical remodeling of brain structures. See our episode with Dr. Levin here.

35:00 - A study reporting the persistence of memories in decapitated planarians. A popular article about these findings.

36:30 - An article reviewing one chapter in the memory transfer history. Another article reviewing evidence for "vertical" memory transfer (between generations).

39:00 - For more recent demonstrations of memory transfer, see here and here.

40:00 - A paper by Dr. Gershman, Dr. Gunawardena, and colleagues reconsidering the evidence for learning in single cells and describing the contributions of Dr. Beatrice Gelber. A general audience article about Gelber following the publication of the paper by Dr. Gershman and colleagues.

45:00 – A recent article arguing for the need to understand computation in single-celled organisms to understand how computation evolved more generally.

46:30 – Another study of classical conditioning in paramecia, led by Dr. Todd Hennessey.

49:00 – For more on plant signaling, see our recent episode with Dr. Paco Calvo and Dr. Natalie Lawrence.

56:00 – A recent article on "serial reversal learning" and its neuroscientific basis.

1:07:00 – A 2010 paper demonstrating a role for methylation in memory.

Recommendations

The Behavior of the Lower Organisms, by Herbert Spencer Jennings

Memory and the Computational Brain, by C. R. Gallistel and Adam Philip King

Wetware, by Dennis Bray

Many Minds is a project of the Diverse Intelligences Summer Institute, which is made possible by a generous grant from the John Templeton Foundation to Indiana University. The show is hosted and produced by Kensy Cooperrider, with help from Assistant Producer Urte Laukaityte and with creative support from DISI Directors Erica Cartmill and Jacob Foster. Our artwork is by Ben Oldroyd. Our transcripts are created by Sarah Dopierala.

Subscribe to Many Minds on Apple, Stitcher, Spotify, Pocket Casts, Google Play, or wherever you listen to podcasts. You can also now subscribe to the Many Minds newsletter here!

We welcome your comments, questions, and suggestions. Feel free to email us at: [email protected].

For updates about the show, visit our website or follow us on Twitter (@ManyMindsPod) or Bluesky (@manymindspod.bsky.social).

Hi friends!

We're taking a much-needed August pause—we'll have new episodes for you in September. In the meanwhile, enjoy this pick from our archives!

_____

[originally aired May 30, 2024]

Maybe your idea of spiders is a bit like mine was. You probably know that they have eight legs, that some are hairy. Perhaps you imagine them spending most of their time sitting in their webs—those classic-looking ones, of course—waiting for snacks to arrive. Maybe you consider them vaguely menacing, or even dangerous. Now this is not all completely inaccurate—spiders do have eight legs, after all—but it's a woefully incomplete and drab caricature. Your idea of spiders, in other words, may be due for a refresh.

My guest today is Dr. Ximena Nelson, Professor in the School of Biological Sciences at the University of Canterbury, in New Zealand. Ximena is the author of the new book, The Lives of Spiders. It's an accessible and stunningly illustrated survey of spider behavior, ecology, and cognition.

In this conversation, Ximena and I do a bit of 'Spiders 101'. We talk about spider senses—especially how spiders use hairs to detect the minutest of vibrations and how they see, usually, with four pairs of eyes. We talk about web-making—which, by the way, the majority of spiders don't do—and silk-making—which all do, but for more reasons than you may realize. We talk about how spiders hunt, jump, dance, pounce, plan, decorate, cache, balloon, and possibly count. We talk about why so many spiders mimic ants. We take up the puzzle of "stabilimenta". We talk about whether webs constitute an extended sensory apparatus—like a gigantic ear—and why spiders are an under-appreciated group of animals for thinking about the evolution of mind, brain, and behavior.

Alright friends, this one is an absolute feast. So let's get to it. On to my conversation with Dr. Ximena Nelson. Enjoy!

A transcript of this episode is available here.

Notes and links

3:00 – A general audience article about our "collective arachnid aversion" to spiders.

8:00 – An academic article by Dr. Nelson about jumping spider behavior.

8:30 – In addition to spiders, Dr. Nelson also studies kea parrots (e.g., here).

12:00 – A popular article about the thousands of spider species known to science—and the thousands that remain unknown.

16:30 – A popular article about a mostly vegetarian spider, Bagheera kiplingi.

18:00 – For the mating dance of the peacock spider, see this video.

20:00 – A recent study on spider "hearing" via their webs.

24:00 – The iNaturalist profile of the tiger bromeliad spider.

29:30 – A recent study of extended sensing in humans during tool use.

33:00 – A popular discussion of vision (and other senses) in jumping spiders.

40:00 – An earlier popular discussion of spider webs and silk.

45:00 – For a primer on bird's nests, see here.

48:00 – An article describing the original work on how various drugs alter spiders' webs.

49:00 – A recent salvo in the long-standing stabilimenta debate.

54:00 – A video about "ballooning" in spiders.

57:00 ­– An article by Dr. Nelson and a colleague about jumping spiders as an important group for studies in comparative cognition.

1:01:00 – A study of reversal learning in jumping spiders, which found large individual differences.

1:07:00 – A study of larder monitoring in orb weaver spiders.

1:10:00 – A study by Dr. Nelson and a colleague on numerical competence in Portia spiders.

1:16:00 – An academic essay on the so-called insect apocalypse.

Recommendations

Spider Behaviour: Flexibility and Versatility, by M. Herberstein

'Spider senses – Technical perfection and biology,' by F. Barth

'Extended spider cognition', by H. Japyassú and K. Lala

Many Minds is a project of the Diverse Intelligences Summer Institute, which is made possible by a generous grant from the John Templeton Foundation to Indiana University. The show is hosted and produced by Kensy Cooperrider, with help from Assistant Producer Urte Laukaityte and with creative support from DISI Directors Erica Cartmill and Jacob Foster. Our artwork is by Ben Oldroyd. Our transcripts are created by Sarah Dopierala.

Subscribe to Many Minds on Apple, Stitcher, Spotify, Pocket Casts, Google Play, or wherever you listen to podcasts. You can also now subscribe to the Many Minds newsletter here!

We welcome your comments, questions, and suggestions. Feel free to email us at: [email protected]. s

For updates about the show, visit our website or follow us on Twitter (@ManyMindsPod) or Bluesky (@manymindspod.bsky.social).

When you hear the word "shaman," I'm guessing a web of associations starts to form in your mind. Perhaps you imagine strange ceremonies and strong substances; maybe you think of an earlier time when magic and superstition reigned. But shamanism is not just some relic of the past, or a curio from exotic lands. It's part of our present, and it will almost certainly be part of our future. This is because the roots of shamanism lie within us all.

My guest today is Dr. Manvir Singh. Manvir is an Assistant Professor of Anthropology at the University of California, Davis and a regular contributor to The New Yorker. He's also the author of a new book—Shamanism: The Timeless Religion.

Here, Manvir and I talk about his fieldwork with Mentawai shamans in Indonesia. We discuss what makes a shaman a shaman and consider the cognitive building blocks that make shamanism so widespread and so appealing. We discuss the shamanic origins of Abrahamic religions. We consider how, over the course of history, shamanism has repeatedly resurged, despite attempts to snuff it out. And we also talk about the various forms and flavors that shamanism takes in contemporary Western societies. Along the way, Manvir and I touch on: drumming, fasting, and the "dark tent"; Jesus; experimental Edens; witches, prophets, and messiahs; glossolalia; disenchantment and re-enchantment; the rise of neoshamanism; Paleolithic rock art; hedge wizards and tech CEOs; Western exceptionalism; and the routinization of charisma.

If you enjoy this episode, I highly recommend that you check out Manvir's book—it's a captivating blend of narrative and ideas and it goes far beyond what we were able to talk about here. I'll also flag that this is Manvir's second time on Many Minds. Back in July of 2020 we had another conversation—broader in scope—where we talked about shamanism but also Manvir's work on witches, stories, and music. So you might check that one out as well.

Alright friends, on to my conversation with Dr. Manvir Singh. Enjoy!

A transcript of this episode is available here.

Notes and links

4:00 – For video examples of shamanic rituals from around the world, see Dr. Singh's recent thread on Bluesky / Twitter.

12:30 – On the idea of "cultural attraction" and "cultural attractors," see here and here. For a recent treatment of the idea of "super-attractors," see Dr. Singh's preprint here.

16:00 – On the case of cultural loss among the Northern Aché, see the recent work by Dr. Singh and a colleague.

17:30 – For more on Dr. Singh's theoretical framework for understanding shamanism, see his earlier academic paper.

19:00 – The 2005 review of altered states of consciousness by Vaitl et al. For more on psychedelics and altered states, see our recent episode with Chris Letheby.

29:00 – Mircea Eliade's classic work on shamanism—Shamanism: Archaic Techniques of Ecstasy.

34:00 – For the book by Martin Riesebrodt on the nature of religion, see here.

36:00 – For more on the human propensity for ritual, see our earlier episode with Dimitris Xygalatas.

43:00 – For one influential interpretation of Paleolithic rock art as evidence for shamanism, see David Lewis-Williams' book, Mind in the Cave: Consciousness and the Origins of Art.

52:00 – For a discussion of psychedelics and organized religion that touches on the "routinization of charisma," see this article by Michael Pollan.

54:00 – For more about the case of Alice Auma, see Dr. Singh's recent piece in The New Yorker.

1:00:30 – For more about neoshamanism and Michael Harner, see the website of the Foundation for Shamanic Studies—www.shamanism.org.

1:04:00 – For the analysis of financial managers by Samuel Johnson, see here.

1:06:00 – For more on the quasi-shamanic flavor of tech CEOs, see Rakesh Khurana's book, Searching for a Corporate Savior: The Irrational Quest for Charismatic CEOs.

1:08:00 – See, again, Dr. Singh's recent piece in The New Yorker in which he discusses Trump and prophet-like status.

1:13:00 – For Dr. Singh's work on other complex cultural traditions, see the website for his lab.

Recommendations

The Sambia: Ritual, Sexuality, and Change in Papua New Guinea, by Gilbert Herdt

The Falling Sky: Words of a Yanomami Shaman, by Davi Kopenawa & Bruce Albert

Many Minds is a project of the Diverse Intelligences Summer Institute, which is made possible by a generous grant from the John Templeton Foundation to Indiana University. The show is hosted and produced by Kensy Cooperrider, with help from Assistant Producer Urte Laukaityte and with creative support from DISI Directors Erica Cartmill and Jacob Foster. Our artwork is by Ben Oldroyd. Our transcripts are created by Sarah Dopierala.

Subscribe to Many Minds on Apple, Stitcher, Spotify, Pocket Casts, Google Play, or wherever you listen to podcasts. You can also now subscribe to the Many Minds newsletter here!

We welcome your comments, questions, and suggestions. Feel free to email us at: [email protected]. s

For updates about the show, visit our website or follow us on Twitter (@ManyMindsPod) or Bluesky (@manymindspod.bsky.social).