Your Inner Fish: A Journey into the 3.5-Billion-Year History of the Human Body book club questions

1. 1.

   Shubin found Tiktaalik by reasoning about what age and type of rock a fish-tetrapod transitional form would be found in. How does this kind of predictive search change how you think about fossil evidence?

2. 2.

   The bones of your arm correspond directly to bones in a 375-million-year-old fish fin. Does knowing that change how you experience your own body, or does it remain abstract?

3. 3.

   The middle ear bones being modified jaw bones is documented in the fossil record through a series of transitional forms. Why do you think this example doesn't appear more often in public discussions of evolution?

4. 4.

   Human hiccups appear to be an inherited reflex from amphibian gill-breathing. Does knowing the origin of a reflex change how you think about it? Does it feel different to call it 'vestigial' versus 'evolutionary inheritance'?

5. 5.

   The recurrent laryngeal nerve is a clear example of bad design that makes sense only evolutionarily. How would you respond to someone who argued that God could have designed it this way for reasons we don't understand?

6. 6.

   Pax6 — the gene controlling eye development — is so conserved that a mouse version works in a fly. What does that level of conservation across 500 million years of evolution tell us about the constraints on biological design?

7. 7.

   Shubin teaches anatomy to medical students using evolutionary comparisons. Does knowing why the human body is structured as it is make it easier to understand or remember? What would be lost if anatomy were taught without evolutionary context?

8. 8.

   Many human health problems — hernias, back pain, difficult childbirth — are direct consequences of our evolutionary history. Does that knowledge change how you think about medicine or about the human body's 'design'?

9. 9.

   The fossil record of the ear bone transition from jaw to ear is unusually complete. Does the completeness of one transition make you more or less skeptical about other claimed transitions for which the record is less complete?

10. 10.

    Shubin moves between fieldwork in the Arctic and the anatomy lab in Chicago. How does his personal experience as both discoverer of Tiktaalik and anatomy teacher shape the book's authority?

11. 11.

    The book argues that understanding human evolution is practically useful — it explains vulnerabilities in our anatomy. Should that utility change how we teach biology in schools?

12. 12.

    After reading the book, which fact about the evolutionary origin of the human body do you find most surprising or compelling?

How to run the discussion

• Pick six to eight, not all of them. An hour of real discussion covers fewer questions than anyone expects, and racing the list is what makes a book club feel like homework.
• Open with what people noticed, not what they concluded. Asking for a verdict first hardens opinions before anyone has heard each other.
• Let the disagreement run. The questions below that split a room are the ones worth the time; the ones everyone answers the same way can be skipped.
• Ask the quiet person a specific question. A direct, narrow question is far easier to answer than an open invitation to contribute.