Posts Tagged ‘evolution’

Saturday’s Biology Recap

January 16, 2010

I hope for this to be a recurring theme on the blog here: looking at recent scientific developments, or age-old scientific arguments, about biology.  In particular, I find the theory of evolution and its opposers extremely intriguing.  Perhaps I’ll expand on that another day.  In the mean time, here are some interesting stories related to the world of biology from the last week.

Of Fish and Flies: The Evolutionary Role of Genes

The NPR takes a look at the role that genes, and gene expression, play a role in evolution.  The stickleback fish and its many varieties are considered.  David Kingsley, a biologist from Stanford University, discusses how the stickleback found in environments with a large number of insects typically have less spines: insects eat sticklebacks by attaching them to those spines.  So it follows that those who grow less spines in that environment have a fitness advantage and are able to propel their genes on into the future.  Having found the gene responsible for building these spines, Kingsley also discovered that the gene plays a role in the development of the brain, jaw, and in the hind quarters.  Even more intriguing, the roughly identical gene is found in all sticklebacks; the difference between the varities is how and where the genes are activated or switched on.

The journalist then takes up a conversation with Sean Carroll, the author of Endless Forms Most Beautiful and, more recently, From Eternity to Here.  Carroll gives a similar example to that of the stickleback, arguing that fruit flies living at higher altitudes are darker than their lower-altitude counterparts because of a genetic mutation changing how these genes are expressed.  As Carroll puts it:

“If we take a big picture of our genome,” says Carroll, “only about 1 1/2 percent of the 3 billion letters of our DNA code for proteins. And we think that several more percent is involved in doing just this. Of controlling how those genes that encode proteins are being used.”

Meat may be the reason humans outlive apes

Of interest to biologists is a simple fact of life: if homo sapiens sapiens share 95-98% of their genes with their great ape relatives, why is it that humans are capable of living to 70+ while great apes almost never crack the 50 year mark?  In the Western world, we could seemingly attribute this discrepancy to advances in technology, in particular the rapid advancements in medical science in the last 200 years.  Still, those living in what we could consider to be more archaic lifestyles (a la hunter-gatherer/forager) have a lifespan that exceeds that of the great apes.  What could account for this?

It has long been suggested that eating meat played a central role in our presently evolved brains.  With a diverse food supply, not only do we have a greater selection of nutrients with which our bodies may be fueled, but also we must be capable of understanding and finding a much larger range of delectables.  As a simple example: an animal that needs to make a mental catalogue of what’s safe, what’s tasty, what is easy to find, for both meat and legumes would almost certainly require greater processing power than a herbivore.  Biologist Caleb Finch at USC suggests that meat also played a role in our improved life expectancy.

Finch argues that many moons ago, our new found diet of raw red meat brought with it a new challenge: chronic inflammation.  To combat this, the humans that evolved a particular cholesterol transporting gene, ApoE3, were more likely to survive, and thus this gene has spread to virtually all of the human population.  ApoE3 appears to lower your risk of contracting heart disease and Alzheimer’s disease, and is correlated with longer lifespans.

Surprising sea slug is half-plant, half-animal

A recent discovery was made of a rare animal: one that produces chlorophyll, a pigment normally found in plants only.  With this ability in their pocket, the sea slugs Elysia chlorotica are capable of doing photosynthesis, a process that allows the slugs to convert sunlight to energy.  The sea slug is thus able to acquire the energy necessary for living.  Though it seems that such an ability, which can be passed on genetically, would allow the slugs to live without eating, but they cannot use the chlorophyll to do photosynthesis until they’ve “stolen” the necessary chloroplasts from algae that they’ve consumed.  Though this ability to produce chlorophyll can be inherited, it is not clear how they’ve acquired this genetic material in the first place.

This story was of particular interest to me.  About two weeks ago, I was listening to a debate on YouTube between a geneticist and the famed Young-Earth Creationist Kent Hovind.  Hovind asked the gentleman (I’m afraid I don’t remember his name) what would disprove the theory of common ancestry, and this geneticist responded that finding plant DNA in a multi-cellular animal would disprove it.  My first thought was that this wouldn’t disprove common ancestry by a long shot.  Instead, it raises questions about what common ancestor these slugs share with plants or, as seems more plausible, how the slugs were able to acquire this genetic information.  That there is an instance of evolution where we don’t know the mechanism really does no damage to common ancestry or evolution as a whole; it simply raises questions about what mechanisms can do what, and which play the biggest role.  The totality of evidence still supports evolution and common ancestry, and it will take a lot of work to unravel that thread.

In monkey babble, seeking key to human language development

The NYT does a fantastic job reviewing the concept of primate language.  It is argued that if we can find some markings of language in other species, we can gain insight into how the complex language shared by humans could have evolved.  In past experiments, we’ve been able to get primates to use human language to a limited extent (the strongest example being that of sign language).  Similarly, we’ve found what appears to be a sign of animals having their own very rudimentary language: Vervet monkeys have specific alarm signals which are called out.  When these signals were recorded and played back, the monkeys responded as if there were a predator to be concerned about.  Though these verbal signals do not have anywhere near the complexity of human language, there do seem to be specific noises associated with specific meanings.

The bulk of the article gives examples of Dr. Zuberbühler’s finding that specific noises are correlated with specific meanings, contrasting this proto-language with the simple fact that chimpanzees have no clear language of their own; you would think that they would having shared a recent common ancestor with other apes and monkeys.  While we are a long ways away from identifying a clear evolutionary model for the neural mechanisms through which language came to fruition, we seem to be just scratching the surface, with many discoveries yet to come so long as we stay the course.

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Evolution, Morality, Atheism, and Invoking Godwin’s Law

November 29, 2009

Undoubtedly one of the most frustrating arguments I engage in with the discussion of atheism is that of how one finds (or knows) their moral compass. Almost every religious apologist (William Lane Craig, being a prime example), seeks to undermine natural morality because it supposedly leaves only one alternative: religion and, more specifically, god provide us our morality. This claim, I think, is false on its face. Looking at most cultures, we see morality that converges on a common principle: do onto others as you would have them do onto you. I think the general perception in the West is that this sort of wisdom was given to us divinely by Christ, but I find it more compelling that the Chinese philosopher Confucius espoused this principle 500 years before Christ, without resorting to god or organized religion to develop such an idea:

“Adept Kung asked: “Is there any one word that could guide a person throughout life?”
The Master replied: “How about ‘shu’ [reciprocity]: never impose on others what you would not choose for yourself?””
– Analects XV.24

Still, the argument often goes that not believing in god but believing in evolution will lead to doing things we would consider immoral. To support such a point, it is often said that Hitler was an atheist, and that his practice of Eugenics (artificially selecting the “lesser” individuals to permit reproduction amongst only the “finest” humans with the purpose of creating a “better” human species) was directly tied to his belief in evolution. Thus, it follows that atheism and evolution can be seen as intellectual positions that in some way endorse or promote immorality.  Personally, I am of the opinion that those who are using Hitler as a key part to their argument are not only mischaracterizing the position they are challenging, but also reducing the real evil committed by Hitler.  Interesting though this argument may seem (and perhaps even plausible to some), I think a careful look at facts, not hyperbole, best explains why this is simply incorrect.

First, let’s speculate a moment on whether or not Hitler believed in evolution. One wonders why, if Hitler believed in evolution and was an atheist, the Nazis adhered to the following guidelines in book banning:

When Books Burn: Lists of Banned Books, 1933-1939

“6. Writings of a philosophical and social nature whose content deals with the false scientific enlightenment of primitive Darwinism and Monism”

“c) All writings that ridicule, belittle or besmirch the Christian religion and its institution, faith in God, or other things that are holy to the healthy sentiments of the Volk.”

Hitler’s literary work, Mein Kampf, also has a similar leaning:

“Hence today I believe that I am acting in accordance with the will of the Almighty Creator: by defending myself against the Jew, I am fighting for the work of the Lord.”

“What we must fight for is to safeguard the existence and reproduction of our race and our people, . . . so that our people may mature for the fulfillment of the mission allotted it by the creator of the universe.”

“The undermining of the existence of human culture by the destruction of its bearer seems in the eyes of a folkish philosophy the most execrable crime. Anyone who dares to lay hands on the highest image of the Lord commits sacrilege against the benevolent Creator of this miracle and contributes to the expulsion from paradise.”

The faith of Hitler has long been a matter of debate because parties generally assume that if we can put Hitler on the other party’s side, we have won the argument.  The general consensus among historians is that Hitler was probably an atheist who manipulated the religious devotion of the German citizens, while presenting himself as a sort of Messiah, to achieve his goals.  Some consider that a “win” for theistic morality, though I think it speaks more to the manner in which adherence to irrational religion can be manipulated; in other words, it speaks to the element of danger involved in forming beliefs that aren’t grounded in reason or science.

But let’s consider exactly what is being suggested here: if person P believes claim C and claim D, does it follow that every person who believes claim C also believes claim D? On the contrary, I think it is clear that we develop our beliefs for a wide range of reasons, and this often creates an asymmetry between multiple claims. It doesn’t take much work for us to discover some beliefs at which we arrived for reasons we would discard immediately for other claims. In the context of this conversation, I think it can be said that we should assess claims not by comparing the actions of others who believed that claim, but by assessing the claim itself. Thus, if we want to determine whether atheism or evolution leads to immorality, we should be assessing atheism and evolution, not the behaviour of those who professed belief. After all, it is perfectly possible for us to take factual information and distort it to support irrational actions or conclusions; in fact, this is the usual religious explanation for why so many bad things, historically speaking, have been done in the name of god.

So now, let’s actually assess whether or not it is possible to be moral without god if we are the products of evolution rather than a divine plan.

It is pretty obvious that most atheists are perfectly able to reconcile their lack of belief with a desire to be good to other people. That is a simple fact borne out by interacting with people of such disbelief. Being a young, white male living in the Western world, I am a part of the largest growing group in religious polling: those who check “None of the above.” Yet, we see that people you know are atheists, and people who are closet atheists, are certainly capable of functioning morally in society.

Of course, it is completely possible that these people are acting irrationally; perhaps their lack of belief really does mean that they should rape, pillage, and plunder, but they have been coerced by the religious aspects of society to behave in what is typically considered a moral manner. Nonetheless, I think understanding our evolutionary background doesn’t hinder us from being moral; it gives a real account of why we are good to others.

I will now pose a hypothesis; I call it a hypothesis simply because I’m not current enough on the literature to claim authority, though I know much of this hypothesis has been advanced successfully in the past, and I believe that evolutionary psychology, neuroscience, and anthropology supports such a hypothesis.

Many moons ago, we were tribal animals. With scarce resources and high competition, we learned that we could be more successful hunter-gatherers if we pooled our skills with others and worked as a team. As one group formed, so did another, and instead of a battle of the individual, we had battles between tribes. This was the first step in developing our moral sense. Within each group, a certain type of conduct was necessary; failing to behave in a way that was condoned by the rest of the group would result in you being ousted, now having to fend against competition with groups as a lonely individual. I would consider this the beginning of codefied rules, as informal as they may have been. Having established that a group code would have inevitably formed, we must wonder how they came up with rules we generally consider to be good or moral. Here, I think the answer is obvious: any actions that are detrimental to the group’s success would be considered wrong. So murder within the group goes out the window; killing off your group members would defeat the purpose of forming the group in the first place. We can also extrapolate our desire to remain in the group to a more individual perspective as well: staying within the group will result in our personal success; we are more likely to stay in the group if none of the members of the group dislike us; and the members of the group are unlikely to dislike you if you do nothing to warrant it. Initially, this was likely a reactive position: we weren’t able to reason it out in advance, but discovered it after a multitude of bad “social experiments.” It wasn’t until much later that we were able to determine such things proactively using our limited intellect, prior to taking action.

So within the group, I think we’ve established that there were good reasons for being moral. A common question is: why would we extend the same rules to those out of our group, particularly to those who are not of our lineage? The answer here is actually a little disappointing. First, we don’t do this very well; humans are very ethnocentric and often cave to in-group thinking. Still, our social nature that was established in our more primitive times encourages us to extend morality and general decency to those who we interact with. The field of neuroscience, where the brain is scanned and images are generated highlighting areas of activity, have shown repeatedly that we respond very well to doing altruistic acts: when we do something for someone else, the areas of the brain associated with satisfaction and pleasure “light up.” We see similar behaviour in other social species as well.

Aside from that, we have some very real evidence that tells us that behaving in what is considered a moral manner is a beneficial plan for us to be successful, and not just pleasing to us personally. Many game theory experiments have shown that a Tit for Tat method, or generally being altruistic until you get burned, will, over the long haul, provide you with greater success, even if we define success in terms of acquiring resources. I think we can go out on a day-to-day basis and experience the same thing: people will generally do better by you if you do better by them. Certainly, there are those who “get away with it”, but that is rarely a good plan for long-term success. What is often called Karma is nothing other than our inability to escape from our past misdeeds; it is the deserved punishment from society for abandoning what is ultimately the best course of action for all of us.

So it seems clear to me that atheism and evolution are perfectly congruent with being a moral person. Our ability to survive and pass on our DNA is better advanced by behaving morally in society than it would be to behave immorally. Still, three issues seem to me to be on the table.

1. Haven’t we made mistakes in the past? Hasn’t our moral sense misguided us many, many times throughout history? If specific morality hasn’t been revealed to us divinely in a simple set of rules (say, the Ten Commandments), how do we determine what is right? Though I think we can argue that the following the golden rule or perhaps John Stuart Mill’s “harm-principle” is something we can intuitively agree on, I want to question whether the divine revelation of moral principles has actually been practiced, or if it works any better. Is it not true that there are extraordinary disagreements on what constitutes morality amongst the religious, even within a particular sect? Is it not true that what is considered moral has changed over time even within a particular sect? I think here of the abolition of slavery, which has significant support from the Bible but was discarded because we discovered it to be immoral. Or, more recently, I think the unfortunately gradual shift on the morality of same-sex attraction, particularly in liberal Christianity, shows the same thing. My point is that even the most steadfast rules asserted by the religious require interpretation and value judgements. We are always discovering more about what works best in a moral sense, and we are always re-evaluating whether our rules and goals are consistent with what we see to be true in natural reality. This is why morality, whether secular or religious, has always been evolving, and will continue to do so in the future. It is up to us as a species to recognize our commonality with all other homo sapiens sapiens, and rationally determine what is the best moral approach for ensuring the best opportunity for success for all.

2. Was Darwin’s theory (though it should rightly be credited to Alfred Russell Wallace as well) really the catalyst for Eugenics? Though I have already argued that in the case of Hitler this is untrue, I would also say that Darwin’s theory had nothing to do with Eugenics whatsoever. Eugenics is the practice of artificial selection (as opposed to Darwin’s theory of natural selection) and this concept is something we understood long before Darwin published On the Origin of Species in 1859. In fact, it was how we were able to domesticate dogs from wolves. Where Darwin changed our understanding was in how the constant tinkering and refining of natural selection produced all species, whereas Eugenics suggests that artifical selection will produce a more successful single species. These are two very different things.

3. If evolution is real (which I believe the evidence supports), wasn’t Hitler still justified in practicing Eugenics? Though we may have disagreed with his stance on a personal basis, could it not be argued that he is attempting to do what is ultimately best for all of us? I say, emphatically, that he could not be more wrong. Our knowledge of nature and of ourselves is incredibly insufficient. We are not in a position to know what is best now or will continue to be best in the future; that is something that remains to be seen. Suppose, for example, that we killed all people with a certain genetic defect. Suppose, however, that a future mutation of that specific gene would allow us to survive through unprecedented changes in our environment. Exaptation and adaptation have shown us again and again that how old parts can be cobbled together to serve new, important purposes. Indeed, I think the best way of ensuring the continued success of the human species is to maintain as diverse a gene pool as is reasonably possible; only by having many alternatives for nature to select from can we be certain that we can respond, in some way, to changing environmental conditions and stave off our own extinction.

It seems quite clear to me that the arguments put forth to discredit atheism do not only a poor job of its stated goal, but fail to put forth a positive argument for theistic morality (such as properly answering the Problem of Evil or Euthyphro’s Dilemma, or the misguidance given in many passages of divine text, whether its the New Testament, Old Testament, Koran, etc). To those who are moral and feel that their morality was only discovered through divine text, I encourage you to give yourself more credit, but I have no quarry with anyone who seeks only to be a good person. It is only when one attempts to take a moral high ground without justification that disagreements will arise, and hopefully that is something we can escape when we look at the evidence and arguments for each position through the shining light of reason.