Author’s note: This is Part Five in a series of conversations with Stuart Burgess, author of Ultimate Engineering: An Engineer Investigates the Biomechanics of the Human Body.
Q. Continuing our series on your University of Bristol colleague Lucy Hyde’s ill-informed claims of bad design, she talks about the pelvis and says that childbirth “presents one of the most profound evolutionary compromises.” You have an entire chapter on the biomechanics of childbirth. Why is she, yet again, wrong on this?
A. Once again, she has this assumption that humans have evolved from quadrupeds. Now a quadruped’s feet are quite far apart when walking, but humans, because of bipedal walking, have our feet close together. So our pelvis is narrower than that of apes.
She’s claiming that human mothers have a painful birth due to the evolution of a narrow pelvis, but the truth is that the female pelvis is a good example of multi-objective optimization. You’re trying to achieve two things that need a trade-off. You’re trying to achieve a birth canal big enough for a baby to come through, but at the same time, you don’t want the pelvis to be too big, because you want females to be able to run efficiently and enjoy running in activities such as sports.
An engineer would say that the female pelvis is the perfect compromise, the perfect size. It’s just wide enough for a baby to be born, but it’s just narrow enough that women can run remarkably fast at sprinting and long-distance running. In the Olympics, it is surprising how women are not that far behind the fastest male athletes. If the female birth canal were any larger to make birth easier, running would be much more difficult because the legs would be too far apart. If the birth canal were any smaller, birth would be really difficult. So an engineer looks at the pelvis and says, it’s the perfect compromise.
Gross Misunderstanding of Design Concepts
What Lucy Hyde may not understand is that all design involves compromise. You can’t have everything; you’re always trading off. With your eyes, for example, you’re trading off side vision with accurate forward vision. Everything you do involves a compromise, and she seems to miss that point with the pelvis.
As to the question of why an intelligent designer would design something that’s painful and risky, Jonathan Witt, the editor of Discovery Institute Press, really helped me on this one. He had a lovely phrase, which I put in my book: “Nothing ventured, nothing gained.”
Some of the most exciting things in life involve a risk. Climbing a mountain is risky, but you don’t then say, well, I’m not going to do it. Skateboarding, BMXing, skiing, they’re risky. But — nothing ventured, nothing gained. And giving birth is risky. And it is your choice. If you don’t like that risk, you could choose not to get pregnant.
Lots of things in life involve a risk. Lots of things in life can be painful. When a baby is teething, it’s painful. Pain is a reality in life. Risk is a reality in life. And childbirth, yes, it’s risky. Things can go wrong. But that doesn’t mean it’s badly designed.
Her article seems to be saying, Why would a designer allow pain in life at all? And that’s getting into, well, that’s the way the world is.
Q. From the Judeo-Christian standpoint, we do have an explanation for why it’s risky and why things go wrong.
A. Yes, Christians have a theological explanation about the origin of pain and, in particular, the origin of pain in childbirth. These are theological questions and separate matters from design in the human body.
Shallow Criticisms
One last point I would make, which applies to all her examples, not just the pelvis, is this: Lucy Hyde cannot propose a better design. With each of her criticisms, she’s not saying, “This is what I would change to make it a better design.” No one has ever explained how childbirth could be better designed. In fact, in my book, I quote from research papers showing that it’s an incredibly well-designed process.