A brief thought on evolution: multi-generational survival
Often people will mention that we are “adapted” to do this or another thing, either indicating some crime of modernity (of course, ignoring the fact that a larger percentage of babies are surviving and people are living longer and healthier than at any time in human history) or trying to point out some example of the glaring perfection of our creation, with either an implicit or vocal reference to divine creation.
For example, obesity is attributed to fat and protein rich modern diets since we aren’t “adapted” to eat these types of foods (despite having found the food in East Africa so unpalatable that we had to learn to crush or cook it to digest it efficiently). Our bad disposition is blamed on a lack of sleep since we aren’t “adapted” to sleep as little as we do (this might be true). Most recently, a book writer blamed our problems with depression on a divorced relationship to nature, given that we are “adapted” to hunt and kill for food and then revel over the blood stained corpse (of course, the writer doesn’t consider that people in antiquity might have been depressed, too).
There may be some truth to some of this. However, “adaptation” implies something about the individual, when evolution, in fact, is about reproduction. We aren’t “adapted” to anything. Rather, certain traits are selected for based on the survival of at least two generations of living things, at least for complex social animals like ourselves.
Simply surviving as an individual does not insure the survival of a species. Living things must first survive long enough to reproduce and then, at least in humans, insure that the children make it to reproductive age. Human babies are horribly weak in contrast to sharks, which are ready to go even before they leave the mother. Further, in the case of humans, a full three generations must live at once to insure long term survival.
Thus, we maintain a tenuous relationship with out environment, where traits do not necessarily favor a single individual, but rather an entire family unit, and these traits may or may not imply perfect harmony with an environment, but rather do the job at least satisfactorily.
Nature cares little for quality as numerous examples throughout our physiology show. To claim that we are somehow “perfectly suited” to a specific environment is just simply wrong. Merely, we have come to a brokered peace (after generations of brutal trial and error, what we eat today is thanks to the deaths of millions, mostly children, who had to die to allow us to do so) with wherever we live in order to allow a few of our kids and grandkids to survive.
This, of course, has deep implications for public health. Some public health problems are known to be passed down from parents to children, but in a multi-generational evolutionary framework, it is possible that certain public health problems can be passed through 3 or more generations at a time, complicating interventions. Certainly, the multi-generational health problems of the descendants of African slaves can be an example of this. How can we intervene to protect the public health over a full century?
OK, back to work.
Thoughts on Environmentalism and an Anthrocentric World
I think that rather than ask whether humans are “more important than other species,” we have to explore the human-nature dichotomy itself. Unfortunateley, discussions on environmental issues seem to start from an assumption that one exists. These discussions, which put humans at odds with nature, generally lose me on three points (though, again, this is not my field of expertise):
1) The intense focus on large mammals. If we are going to convince ourselves that “nature’s” needs are more important than our own (or simply worth considering) we have to eliminate the idea of a hierarchy of species and consider all living things as equally important. It often seems that conversations become less holistic and more mammal-centric. Given that we are mammals and hard wired to like cute and furry things (particularly those small and weak), this is to be expected. However, the urge to protect things like ourselves makes it impossible for humans to objectively rank the importance of living things.
How often do you hear about people screaming to save snakes? Perhaps it happens and I just don’t hear about it. Clearly, big furry animals are an easy sell.
2) The idea that “species” are distinct entities, the number of which needs to be maximized at any cost. Preserving more species is seen as a goal, when in fact, the word itself is not uncontroversial. “Species” is a rough and artificial concept created by humans to assist in our understanding of the world. Even scientists can’t agree on what a species is, given that the situation that determines how a species is defined differs by type of animal and context (and history).
Take the Zebra, which comes in three main flavors, though I’ll focus on two. The Grevy zebra is Equus grevyi and the plains zebra is Equus quagga, different “species” by classification, but able to breed with one another and create offspring which are able to reproduce. The two “species” are distinct from one another only in superficial morphological features (stripes and size) and behavior.
Gravy’s, though genetically indistinct from plains zebras, are listed as endangered, which gives them certain benefits and allows Kenya (for example) to legally restrict grazing for Maasai goat herders, with the support of international groups. It’s a simplistic example, but it makes little sense to me to ask that humans make sacrifices based on a flawed concept of what makes a “species.” It also makes little sense to create policy which impacts the lives of Africans based on a false paradigm created by 19th century Europeans (“Gravy” was a French President). Yet, here we are.
An aside, but I often think that people really believe that “species,” particularly large mammals, are individuals with distinct personalities and collective thought patterns. From the animals’ standpoint, extinction isn’t an issue. Rhinos don’t hold regular meetings and worry collectively about extinction. Individual rhinos are merely concerned with eating enough grass and mating when necessary.
3) The concept that nature is a fragile and static entity which would be ultimately benefit from our non-existence. This stems from traditional dichotomies of “man” and “nature” where man operates in his (male) world and nature operates in an entirely separate and unchanged sphere. In the West, this goes all the way back to Genesis. It is a simplistic and useless concept and does more harm than good.
Nature is a dynamic and constantly changing system of which we are one part. We create nature “reserves” which are thought to “preserve” the “natural” state of “nature” but even these are artificial, human constructed spaces, as we have dictated the location and killed all our large wildlife. We approach them are “preserves”, but forget that we have altered the system (by, for example killing the wolves or cutting all the pine trees in Michigan). Thus, arguing for the “preservation” of nature is somewhat disingenuous, since even by advocating for what part of nature needs to be preserved, we are writing its rules.
The question of whether the world would be better or worse off without us is fairly moot since humans are defining the terms of “better” and “worse.” Moreover, from the German cockroach’s (Blattella germanica) standpoint or the Black rat (Rattus rattus), humans could be considered a great thing as we tend to migrate and take our pests with us. If it could, Plasmodium falciparum should worship us like a God, since it wouldn’t exist without us.
I don’t see man as separate from nature. For better or for worse, we are a part of it. But after we have run our course, the world will go on without us. “Nature,” however it may be defined, has shown itself to be a tough beast in the past. Even if the entire planet became desertized (is that a word?), life would continue to exist. One day, with or without us, all life on Earth will cease to exist.
The most salient questions should revolve around how our environmental impacts affect our long term survival for humans. Focusing on our own needs is the only sustainable strategy (though I despise the word).