Thursday, April 15, 2010

I get e-mail too!

T. G. Dobzhansky, a prominant evolutionary biologist once said...

"Nothing in biology makes sense except in the light of evolution" 

Recently, I received a request from a Tom Paine's Ghost reader to answer some questions about public perceptions of evolution. The questions, along with my responses follow.

Reader: How is evolution relevant to the lives of everyday people?

TPG: I will here talk about medicine, childhood obesity, and sex.

ResearchBlogging.orgThe first topic that springs to mind when I think about this question is antibiotics. Most people reading this will have, at one point in their life, been prescribed an antibiotic. The more people understand evolution the more likely they'll be to use medicine in a more effective manner. Rather than a doctor saying "take these pills twice a day everyday because I TOLD YOU SO" people who understand the underlying REASON they should take their entire course of prescribed medication will be more likely to do so. This in turn leads to a more aware and educated public who have the concerns of both society AND themselves in mind as they make health care decisions.

For people already fearful of pharmaceutical companies and medical doctors, it might be easy to misinterpret what I just said in the last few sentences to mean this..."understanding evolution will help people take more antibiotics"  THAT IS NOT WHAT I AM SAYING. If fact, understanding evolution, and specifically the rapid evolution of asexual, gene swapping bacteria would make a person less likely to go ask for an antibiotic straight away.  BUT, in the case that an antibiotic is in fact needed, that person would be more likely to use that medicine in a more effective manner. 

Understanding evolution by natural selection does not mean individuals must succumb to the brutality of nature. Quite the opposite is true.  Understanding evolution gives us the ability to reason our way out of the stone age and into an ever-updated age of enlightenment.

The next topic that comes to mind is obesity.  Obesity is becoming a worldwide epidemic. It has become such a rampant scourge that children born in the United States today will be the first generation of Americans whose life expectancy will actually be shorter than their parents’ life expectancy. This is the first time mortality rate will have gone up since the industrial revolution.  As the gap between third and first world narrows more and more people become obese. The reasons starving people still exist on earth is another topic based in politics an economics, and one Frances Moore Lappe addresses quite well. But here I am focused on evolution literally going haywire when it comes to the pre-loaded sweetness software that comes standard with nearly all homo sapiens operating systems.     Why does simple sugar taste "good" or sweet - to most people? In the context of evolution this question has an answer.  Sweet foods taste sweet because they have a lot of calories.  Organisms that had an intrinsic desire to taste sweet things could survive and reproduce. Those unable and perhaps unwilling to seek out the nutrition they needed went extinct and therefore most humans now like the taste of sweet things. Why is fruit sweet and crushed seed bitter?  For that answer one must take the evolutionary perspective of the plant in question. The plant wants It is beneficial for the mother plant if the seeds are transported, therefore incentive has evolved for hungry animals to ingest the seed. The incentive being a coating of sugary goodness - the fleshy part of most fruit. But if that animal happened to have the unfortunate accident of being born with a stomach enzyme that would destroy the seed's hard shell, then that animal would probably not live to pass its faulty genes on to the next generation.  This is so because many plants have evolved to contain toxins in their seeds (IE apple seeds have cyanide inside them). This makes sense, because if every time an animal ate the fruit from a plant it destroyed the seeds, then that plant would not survive to prosper on down through the generations. But, if the plant had these toxins it would assure that only friendly animal stomachs transported their seeds to new planting grounds. Going back to obesity, the problem of rampant obesity arises in many cultures because calories become so easy to get and in such massive quantities that this, once useful, survival mechanism turns into a health hazard. 

Though there are many more human-centered topics an understanding of evolution would help us cope with I'll limit myself to three. The last being sex.  I said before that understanding evolution does not mean we must all succumb to the brutality of nature.  This is a funny argument in the daunting topic of human sexual interactions.  As gross as this rhyme sounds, the "urge to merge" as my father so disgustingly put human inclination towards sex,  is known to be built into the wiring of most human brains.  Why do humans desire sex? Why do men cheat on their wives? Why do women cheat on their husbands? Why do people stay faithful to one another? - I'm not arguing that a cheating man or woman can plead - "evolution made me do it" but I am saying that evolution - "survival" - does play a big role.  Just like humans have learned that eating food off the ground is not very healthy or safe, we've also learned that sleeping around is not very healthy or safe. Though evolution might make our brains want sex our reasoning brains tell us no (most of the time), or at least give us the insight to use birth control of some sort.  There are several methods society uses to try and curb rampant sexual hedonism. Religions try by bringing in fear of eternal damnation, but understanding evolution gives a less fear-mongering lesson in why the monogamous mating strategy might be a good idea.  Here I will digress a bit into my observations of society. I acknowledge that classic nuclear families (where man and wife stay together for their entire lives) do exist and I am happy to see those scenarios, but I also observe that it the real world many couples split even after having children.  I'm not making a value judgment here but I am saying that society might become less judgmental of alternative family structures if the tendencies and behaviors built into all organisms were understood and appreciated more widely. 

Reader: Is evolution important for the public to understand? If so, why?

TPG: In my opinion, yes, it is extremely important for the public to understand evolution. I think this because of the atrocities history has seen come out of the misunderstanding and misinterpretation of evolution, namely world war II and the holocaust. A most egregious misinterpretation of evolution is the fallacy that evolution has a goal. There is no such thing as "highly evolved" only highly adapted. People have, since the publication of On the Origin of Species tended to take the human-centered view intrinsic to most religious belief systems and apply it to the understanding of evolution. This type of misplaced certainty lead to the eugenics movement - technology misapplied in the most horrific way imaginable.  The observation that organisms evolve via natural selection because of descent with modification does not mean humans are at the top of some scheme to get to an evolutionary apex. With this more sophisticated understanding of evolution one can easily see that some bacteria are far more adapted to their environments when compared to homo sapiens.  In terms of survivability  some extremeophile bacteria are  far more likely to survive an extinction level event such as the disaster that lead to the annihilation of the dinosaurs.

It has taken hundreds of years for the concept that earth is NOT the center of the universe to be accepted. So the relatively nascent notion of evolution by natural selection (and its blind eye to human accomplishments) is only beginning to be comprehended and appreciated by the global population here in the year 2010. Sadly, in the United States acceptance of evolution is disturbingly low and could be playing a role in our rapidly declining position in the world regarding science math and engineering skills.  Even more sad is the fact that leadership at the National Science Foundation (NSF) and a members of the National Science Board (NSB) - do NOT think data collected about the public understanding of evolution are real "indicators" of our national average understanding of  science in general. 

Reader: Natural selection, or survival of the fittest as Herbert Spencer coined it, is often thought of as a ruthless force where the strong survive and the weak are left to die. Can natural selection favor qualities like cooperation and altruism, as Dawkins and others have proposed?

TPG: Of course evolution can favor cooperation and altruism. I use the fact that these characteristics exist at all to prove that evolution CAN favor them. These concepts can be further refined and understood as "reciprocal altruism"   Here I refer to the later chapters of Richard Dawkins' book The Selfish Gene. Dawkins does a nice job using game theory to explain how reciprocal altruism beats out other strategies and becomes a sustainable system with all other factors remaining the same, food supply, territory, etc. etc.  But I will repeat myself.. Understanding evolution by natural selection does not mean individuals must succumb to the brutality of nature, quite the opposite is true. 

Reader: What is the relationship between evolutionary theory and the origin of life? Are they separate fields and topics, or is there relevant overlap?

TPG: In short, I see no overlap between these two areas of study. In my understanding, the process of evolution and abiogenisis (literally the origin of the first life form) have nothing to do with one another. From logic this is easy to see.  Put it like this - if there is a rule like 1+1 = 2  was that rule true before any person ever existed to think of the number 1 in the first place?  It's like that.  The concept and rules of evolution are true no matter if we were having this conversation 4.5 billion years ago or two days from now.  Observing how evolution works that is biology, that is chemistry, that is geology etc etc.

Miller, J. (2006). SCIENCE COMMUNICATION: Public Acceptance of Evolution Science, 313 (5788), 765-766 DOI: 10.1126/science.1126746

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