When speaking about evolution many people tend to use the past tense, as if we’re no longer evolving, as if our species is the same now as it was during the Paleolithic period. This is false. Similarly, many people believe that in order to maximize our health and longevity, we should imitate the lifestyles of our Paleolithic ancestors. According to Marlene Zuk, a biologist at the University of Minnesota, this is also false.
There are those who have embraced what anthropoligist Leslie Aiello calls “paleofantasies” or nostalgic visions of, as Zuk writes, “a time when everything about us — body, mind, and behavior — was in sync with the environment.” In her witty and well-researched prose, Zuk debunks these pseudoscience-based conceptions and proves that humanity did not have a time like the kind depicted by these fantasies; evolution has always been and will continue to be a key player in our species’ future.
Let’s take a closer look at what she means. Contrary to the belief of many, evolution is not a linear phenomenon; there is no straight and narrow path from one point to the next. Rather, Zuk prefers to think of it as a drunkard’s walk; there are detours, sidetracks, branch-offs, and reinstatements. The course is determined by environmental input, genetic mutations and natural selection.
Among many interesting points Zuk offers, her thoughts pertaining to immortality are particularly striking. While there are many steep prices to pay for immortality — watching friends and family die, never leaving a mark, etc. — there is one price greater than the rest: In a few thousand years you will realize that you’re an antiquated model of a now considerably more advanced species. You will be shorter, slower and dumber than your counterparts, and it’s very likely that no one will want you around.
Paleofantasies shouldn’t be applied to our current lives. For one, Zuk believes that relinquishing our grasp of them will allow us to live better by paying attention to how our bodies respond to healthy food and balanced diets, rather than going for any one extreme. Secondly, it may help us be aware of the type of footprints we leave on our environment, since we change it much like it changes us. Thirdly, hopefully we will strive for a better relationship with other organisms by letting go of our imagined monopoly over evolution if we accept that we all evolve in order to coexist.
Brain World had a chance to speak with with Zuk, author of “Sex on Six Legs: Lessons on Life, Love, and Language from the Insect World,” and “Paleofantasy: What Evolution Really Tells Us About Sex, Diet and How We Live.”
Brain World Magazine: Why did you embark on the very long endeavor to write “Paleofantasy,” which is about evolution and how we misperceive it?
Marlene Zuk: I suppose a lot of it came out of the long-standing frustration dealing with people who misunderstand it. At some level [evolution] is complicated, but, on another level, it really isn’t. And yet it seems like there is so much around us about how we can and can’t learn things from our ancestors, or from our evolutionary history that’s just misplaced. So scholars need to set the record straight and say, “No wait, here, this is how it really works!”
BW: Do you feel there are a lot of scholars trying to do this, or is there a certain amount of intellectual boxing-in?
MZ: I think there are a lot of scholars trying to do this but I think it’s not always easy. The material is complicated; I relied a lot on my colleagues and people who were doing some of the research. I was actually just telling someone that more than anything else I’ve written, I really had to tear myself away from continuing to do the research because new and exciting things are happening everyday — where you look at a journal and you say, “Ooh, I should really include that article,” but then again, the same thing will happen tomorrow, and the next day, and the day after that. So at some point you have to say, “I’m done.” I had to stop so that my editor could work; but I think that there are a lot of people trying to convey this.
BW: Your background is in biology, evolution and also behavior. In the last 3,000 years, people have assumed that evolution’s stopped, but you showed that in smaller organisms, evolution can occur in as many as a few generations back. As a behaviorist, how do you explain it?
MZ: It has been a really big thing in behaviorism. OK, people are alright with the fossils, and we can see that a horse’s bone changed over time because we have the different fossils from different periods to prove it. But behavior is so flexible to begin with that it’s not fossilized in any way. So how can you talk about behavior evolving the way you talk about traits like leg length evolving? When you get down to it — this has been a question that people who study animal behavior have been asking for as long as people studied animals. Behavior is a trait like all the other traits. It really isn’t any different than leg length because like leg length, it results from genes and input from the environment.
All traits, all the time, are always the result of input from the genes and input from the environment, so people will grow shorter if they don’t eat enough, but their leg length will also be determined by the genes and environmental input; there will always be an interaction there. Behavior is the same way! It may be more difficult to see and figure out — which component came from the environment and which component was the input from the genes — but it’s actually liberating to realize that it’s not any different. People ask, “How does behavior evolve?” and they ask that while throwing a stick for their dog that a few thousand years ago was an animal that would tear your arm off if you were in the same room with it. So, you’re going to tell me that behavior doesn’t evolve? Of course it does! We made it evolve, at least in our pets!
BW: Your argument is really compelling but still, half of the American population does not believe in evolution!
MZ: Believing in evolution is somewhat of a strange way to put it! I mean whether you believe in the germ theory or not, you’re still going to get sick with the flu; your belief is immaterial to the germ theory belief.
And then there is the whole argument about how scientists use the word “theory” differently from the rest of the general public. To me, this is almost all part of a great lack of understanding of and an appreciation for science, and for how much it explains about the world. To scientists, the evidence is overwhelming … Evolution and natural selection is just as well-supported as any other scientific theory we have. I think that people are stumped by the idea that, for however long, it’s not just fashions that are going to be different; our core would be different because evolution is constantly happening. I think it really is hard to think about it.