The Skeptics' Guide to the Universe · Dr. Steven Novella

The Skeptics Guide #1081 - Mar 28 2026

March 28, 2026

The windows finally open. Stephen Novella gives the date, the full panel checks in, and spring weather turns into a dry comparison of Northeast seasons and L.A. seasons. L.A. gets its seasons too: fire, heat, atmospheric rivers, and maybe oil spills. That banter sets the table before the excerpt cuts toward science. Then the cloning story lands. Over twenty years, researchers produced more than 1,200 cloned offspring and kept the line going through generation after generation. Early on, it looked fine. Behavior and lifespan did not throw obvious warning signs, which makes the later collapse feel worse than a simple failed experiment. Generation 27 shifts the mood. Birth rates decline, the work keeps going, and by around generation 57 the panel describes things as seriously grim. Generation 58 is the wall. The animals die out, and the researchers cannot keep the cloning chain alive. The mechanism is the interesting part. The panel looks past the head count to accumulated mutations and DNA abnormalities, while being clear that the full explanation still is not settled. Nuclear reprogramming comes in through the genome and epigenome, with the panel separating inherited coding from the layers that help control which genes turn on and off. That distinction matters. The experiment needed an epigenetic modification reagent to promote nuclear reprogramming, so the cloning process was never a clean copy button. The science stays messy. The skepticism here is not anti-cloning drama. It is the colder point that repeated cloning can look stable while biological costs pile up out of sight. Then Descartes gets clipped. The ending ties his name to Cartesian dualism, with the panel joking that he should have doubted that one harder. Very SGU: banter, definitions, genetic detail, and a little philosophical side-eye without pretending the evidence is neater than it is.

As heard by us

SGU turns a long cloning experiment into a clear discussion of epigenetics, mutation buildup, and why uncertainty belongs in science.

The Skeptics' Guide to the Universe #1081 opens in familiar panel mode, with Stephen Novella, Bob Novella, Cara Santa Maria, Shane Novella, and Evan Bernstein turning spring-weather small talk into a science segment with sharper stakes.

Read the full review in PlayNext →

Why you'd press play

You want a skeptical, plain-English breakdown of a cloning study that ran for 20 years and then hit a wall.

Read the full recommendation in PlayNext →

Listen to the show on

Apple Podcasts Spotify