Radiolab – “The Spark of Life”

Date: September 19, 2025
Host: Molly Webster
Guest: Narosha Marugin (Applied Biophysicist, Wilfrid Laurier University, Canada)
Theme/Purpose:
This episode explores the enigmatic border between biology and physics, focusing on the astonishing idea that all living things emit light—a phenomenon that may not just be a byproduct, but could have deep implications for signaling, health, and perhaps consciousness itself. Through conversation with biophysicist Narosha Marugin, the episode investigates the science, skepticism, and possible future of “biophoton” research—even touching life’s brightest beginning and its “final salute.”

Key Discussion Points and Insights

1. The Biology-Physics Divide and the “Lock-and-Key” Dilemma

• Molly introduces the classic view that biology and physics are separate fields—biology being “messy, physical stuff” and physics as “the abstract: waves, energy, invisible particles.” (01:14)
• Narosha describes her discomfort with the prevailing “lock and key” model of cellular signaling, where proteins randomly bump into each other to activate biological processes. She questions the feasibility of such a process occurring so quickly in the chaotic interior of a cell.

  “Imagine you're one of those janitors with a big ring of keys. How do you find that right key for the right lock in that right amount of time to induce signaling?... The probability of you finding your shape in one thousandth of a second…” – Narosha Marugin (04:46)

• Molly echoes the incredulity:

  “It's like the janitor took the ring of keys and just threw it at a lock. And somehow the right key on that ring gets into the lock and, like, it makes it across the space, even though there's so so much in the middle.” (05:36)

2. The Leap: Could Light Be the Fast Messenger in Biology?

• Driven by this skepticism, Narosha asks: Could there be a faster, non-physical signaling mechanism—like light?
  • She draws an analogy to “tap card” access vs. an old school lock-and-key:

    “What can be faster that cells can use to communicate? What is the fastest signal that we know? Light.” (07:08)

• Narosha discovers research from the 1920s by Russian biologist Alexander Gurwich, who found evidence that onion roots emitted light, suggesting all biological life emits light (biophotons).

3. Biophotons: The Science of Biological Light Emission

• The conversation establishes that all living cells emit photons, though the light is extremely faint and not visible to the naked eye.

  “Every cell in your body does give off light.” – Narosha Marugin (09:12) “Heart cell, liver cell, brain cell...literally everything that is alive emits light.” – Narosha Marugin (09:33)

• The light’s wavelength (color) can vary depending on the metabolic activity of the cell.

  “Different rates of metabolism will induce different wavelengths of light. So different colors.” – Narosha Marugin (10:26)

4. Where Does the Light Come From?

• The likely source: mitochondria, the cell’s “powerhouse.”
  • As electrons get passed along the mitochondrial chain and drop to a lower energy state, a photon (light energy) is emitted.

    “In that process, the electron goes from a high energy all the way down to a low energy state…during that hop, it releases energy, which is light.” – Narosha Marugin (12:20)

• Estimates of photon emission:

  “If you take a dish of brain cells…probably get around 100 photons a second.” – Narosha Marugin (13:30) “When you activate them…signals anywhere from 1,000 to 2,000 photons a second.” – Narosha Marugin (13:59)

5. Scientific Skepticism and Shifting Attitudes

• Narosha recounts professional resistance:

  “Oh, this is noise. This is not science. You're going to jeopardize your career. Stop this. Go back into cell biology.” – Narosha Marugin (15:01)

• The field has become more accepted internationally, though many scientists now see biophoton emission as “noise” rather than meaningful.

6. Biological Purpose: Is Internal Light More Than a Byproduct?

• The episode explores whether this light is merely “waste” or could serve a signaling role—perhaps carrying information like a neural “fiber optic cable.”
  • The sun’s role in vitamin D synthesis and circadian rhythms is brought up as evidence of biological light sensitivity.

    “We are essentially like energetic converters converting sunlight into energy for our life.” – Narosha Marugin (17:43)

• Narosha details ongoing research into whether internal cellular photonic emissions also play a purposeful role, noting that cells have evolved to both emit and receive light.

  “There are many, many elements of our cells that are able to absorb light.” – Molly Webster (18:26)

Notable Quotes & Memorable Moments

• “So I was a bio major, and we had to take maybe one physics class, and then we never thought about it again.”
  – Molly Webster on the bio/physics split (01:14)

• “When I burnt myself…how quickly that information of me burning my hand went into my body…Think of the probability of you finding your shape in one thousandth of a second.”
  – Narosha Marugin’s scientific epiphany (02:37, 05:25)

• “Biology emits light?”
  – Molly Webster’s disbelief (08:20)

• “Why can't I see it?”
  – Molly Webster, probing further (09:56)

• “We are essentially like energetic converters converting sunlight into energy for our life.”
  – Narosha Marugin (17:43)

Timestamps for Key Segments

• Bio/physics split and the lock-and-key model – 01:14–06:57
• Light as a biological signal & the Gurwich discovery – 07:08–09:12
• Every cell emits light (biophotons) – 09:12–11:04
• The mitochondria and photon emission – 11:14–13:16
• Photon measurement and metaphor (“cellular fireworks”) – 13:23–14:26
• Scientific skepticism (“noise, not science”) – 14:38–15:20
• External vs internal light, vitamin D, sun as a source – 16:09–18:26
• Purposeful use of light in the body? The unanswered question – 18:49–19:31
• Breaking: Can the cell’s cytoskeleton guide light? – 24:18–27:02
• Microtubules as “fiber optics” – a new hypothesis – 26:28–27:02
• Biophoton links to neural activity and information transfer – 27:19–28:49
• Could biophotons be tied to consciousness? – 28:55–29:13
• Potential for medical diagnostics: cancer detection – 29:50–31:47
• Life/death as photon signature: “death flash,” hospice anecdotes – 32:34–34:40
• The “life flash” at conception (calcium influx video) – 35:05–36:33
• Personal reflection – meaning of light at start and end of life – 36:15–37:16

Theoretical and Practical Implications

1. Diagnostics and Medical Use

• The potential use of biophoton emission to detect cancers at inception, before a tumor forms, based on their unique “light signature.”

  “With confidence, I can say as we've published papers on this now, so we can tell whether there is cancer within an animal as soon as that we've injected it... within day one there's something. There's cancer there.” – Narosha Marugin (31:11)

2. Philosophy, Life & Death

• Photons as a mark of life:

  “You can tell when an animal is alive and dead just by looking at their photon signatures.” – Narosha Marugin (32:23)

• Speculative accounts of a “death flash” as the body’s final energetic release at death; similarly, a “life flash” at fertilization (the calcium influx and photon emission).

3. Open Questions

• Is the light meaningful, purposefully used by biology, or only a side effect?
• Could the cytoskeleton or microtubules function as a “fiber optic” guidance mechanism for intracellular signaling?
• Might biophotons relate to neural function or even consciousness itself?

Final Reflections & Emotional Note

Molly closes with a personal story, connecting the science to her father’s final days in hospice.

“I did not see a flash of light. I certainly felt one. I’m going to miss you, Pops. Thanks for always listening.” (37:53)

Summary Table: Biophoton Concepts

| Concept | Description / Key Insight | Notable Quote / Timestamp | |----------------------------------|--------------------------------------------------------------|------------------------------| | Every cell emits light | All metabolically active cells emit photons (“biophotons”) | 09:12–09:33 | | Source: mitochondria | Mitochondrial electron chain reaction emits photons | 12:20–13:16 | | Purpose: yet unproven | Hypothesis: photons could communicate biological information | 18:49–19:31; 27:19–29:13 | | Medical application: cancer | Cancer cells have discernible light signatures | 31:00–31:47 | | Markers of life & death | Living vs. dead can be distinguished by photon emission | 32:23–33:40 | | Life's “spark” and “final salute”| Photon emission at conception and (anecdotally) death | 35:15–37:16 |

For Further Listening/Reading

• Research on Alexander Gurwich and the “mitogenetic ray”
• Studies on biophoton emission and the mitochondria
• Research and videos on the fertilization “calcium flash”

Radiolab, ever curious, points to the twilight zone between hard science and humbling mystery, inviting us to reconsider what it means to be alive—and perhaps, what it means to glow.