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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.


Ebola: we don’t have time to waste

Ebola is a cool disease. It transmits among fruit bats in the area in and around the Central African Republic. Apes live in and under the trees the bats live in and ingest their feces. Humans who ingest the apes pick up the virus when slaughtering the animal, or so some think. The truth is that no one really knows for sure.

Contacts between humans is increasing as settlements expand and a demand for meat increases. Lacking access to formal methods of employment, individual sellers happily take advantage of market demand and a thinly profitable trade in bushmeat profulgates. Meat equals success and in the place of professionally or pastorally raised beef, which is mostly unavailable to poor people in countries like Liberia and Sierre Leone, people eat the monkeys, chimps and many other of our cousins which are able to harbor the many of the same pathogens we do.

One person gets sick. He or she has no access to formal care because his or her government can’t or won’t provide it so he remains at home. The family consults the local herbalist who provides some medications which offer temporary psychological relief but nothing more. As time ticks on, the victim becomes even sicker until the situation becomes so serious that the family has no choice but to carry their dying loved one to a health clinic 20 km away from their house. Along the way, everyone carrying him or her touches infected feces and vomit and three weeks later the process is repeated.

This could have all been avoided if rural economies were developed enough so that a mass migration to urban areas wasn’t necessary, had there been safer sources of meat available for an affordable price, were there sufficient jobs which wouldn’t necessitate the bushmeat trade, were the governments of Liberia and Sierre Leone effective enough to place a proper health facility close by to patient 0’s house and if health care was dependable enough to be able to spot and deal with an Ebola case.

Ebola is a conflation of ecology, economics, sociology, culture and politics, all mixed together to create conditions for one of the worst health crises the African continent has seen since HIV. It’s going to erase any of the gains of the past decade and collapse the already struggling health systems of some of the poorest places on the planet.

Meanwhile, the United States is having another 9/11 moment and this is where I’m starting to get quite concerned. Panic is about to become policy. Fears of global terrorism prompted our entry into Afghanistan, which might have been justified. But it also paved the way for the invasion of Iraq, which, from the beginning, was a disaster waiting to happen. Out of 9/11, we got the Patriot Act, a massive expansion in government powers to search, seize and detain and America stood by and allowed it to happen with little debate.

I am not a Libertarian, though keep getting accused of being one. I believe in public schools, public health care and government oversight of dangerous industries. So there. John Galt wouldn’t be much into me (but I guess from the far, far left anyone looks like a Libertarian).

I am, however, despite my leftist pedigree, quite concerned with the rights of individuals and the potential for panic and ignorance to lead to a rhetoric that can quickly spiral out of control and veer seemingly caring people away from the direction that the moral compass would normally point us in. I am remembering how many Americans supported torture during Bush II and wondered how many of them would support torture were it to be practiced on their own children. Though seemingly alarmist, I think that we need to be extremely careful.

Enough about me. The reality of Ebola is that it is a man-made crisis. Forest dwelling locals have eaten bushmeat for as long as humans have lived there but there is little evidence that there has ever been a large scale outbreak like the one we are currently experiencing (though history in Africa is often obscure). As I noted earlier, many forces are at play, all of which are associated with the rapid social change that Sub-Saharan African states are currently experiencing.

Some of these forces are inevitable. Population growth, as it did in Europe and Asia before, has led to the creation of mega-cities. The connections, however, between the rural and the urban, however have not been severed. People are going to do what they do, regardless of risk, particularly if they can make a buck meeting some market demand.

Some forces, though, are avoidable. While health care did not initiate the crisis, it helped drag it along. Liberia and Sierre Leone can boast to have two of the worst health systems in the world, but their poor capabilities are hardly unique in Sub-Saharan Africa. NGOs and missionary groups work to plug some of the gaps, but the reality is that without a concerted and proactive effort from the governments of those countries, the system will never improve. International funding is too poor and weak national economies and top heavy tax structures can’t adequately fund these systems domestically. Poor funding leaves many clinics, particularly those in rural areas where these outbreaks begin, without supplies, trained staff and diagnostic equipment. In Kenya, Malawi and Tanzania, I’ve seen more than one rural clinic without power or clean water. Worse yet, Ebola outbreaks, though devastating, are infrequent so that more pressing needs like malaria, diarrheal disease and HIV eat up the brunt of the already scarce funds clinics receive. Pathogens not only compete in the wild, but also for funding and support. This leaves many rural health workers without the protective gear they need, so that they work are the highest risk for death from diseases like Ebola.

What can we do? First, we can calm down. In the United States, the reality is that one of far more likely to be killed by an oncoming car than from Ebola and the probability of sustained transmission extremely low. Though people like to view domestic transmission events such as the one in Texas as failure, the reality is that public health and medical resources move much more quickly and effectively in Texas than in troubled Liberia. Much is made over Ebola’s lethality, but a patient who is found to be infected in the United States has a vastly higher likelihood of surviving than one in Liberia.

Second, leaders can stop spreading and capitalizing on misinformation. While attractive, promoting hysteria only leads to bad policy. The tendency in America is to view as some kind of apocalyptic movie scenario. While fun (not to me), the reality is that there are people in the world who are dying who shouldn’t be. Moreover, closing schools because someone knows someone who knows a Liberian is just simply unwise and counterproductive in the long term.

Third, the international community needs to engage the governments of Liberia and Sierre Leone to improve their public health infrastructure. This is not an easy task. The histories of working relationships of international health bodies and developing countries governments are fraught with failure. Mutual distrust, corruption and indifference of political leaders to the plight of their constituencies has created a mostly untenable system. However, providing supplies and training come at little cost is a mostly uncontroversial affair.

How long will this last? No one knows but it is inevitable that, even if this epidemic is brought under control, it certainly won’t be the last of its kind. We don’t have time to waste.

Sunburn…. and thoughts on the dynamic nature of genetics, disease and politics

Not a tree to stand under.

Not a tree to stand under.

I just got back from meeting with our field teams on Lake Victoria in Mbita Point in western Kenya. Normally, I wear up to three layers of clothing, but for some reason, I only wore a single shirt so that an 3cm square area of skin, which would have normally been covered, was exposed to the sun.

Over the course of the day it went from white to brown to red to black. I’m thanking Columbia clothing that the rest of my isn’t black as well.

It sounds really trivial; I got a sunburn. But I’m a really pale guy, and there’s a reason for that. The bulk of my genetics come from northern Europe, an area which is mostly dark, and even when it’s not dark, the sun is filtered through a thick wall of air and moisture.

My skin is not suited to Kenya’s blistering sunlight. My Japanese colleagues inexplicably do their best to keep themselves from tanning. Honestly, I’m jealous of their ability to brown in the sun and don’t really understand why they don’t take full advantage of their innate ability to protect themselves.

In short, I was born pale white, but wish I were black or at least able to brown. It would make field work easier.

Which brings me to this. I often hear people engaging in common conversations about what humans “were meant to do,” as if we were created as complete biological entities designed to perfectly perform specific assigned tasks within the narrow confines of specific environments.

This is a creationist view, but it’s interesting that even non-Christians in the West readily use the same assumptions and terms that are common to religious fundamentalists. The idea is that everything that came after we were kicked out of Eden, in this case East Africa, the birthplace of humanity, is an abomination. Whatever health or social problems we suffer is payback for violating the terms of our initially assigned roles as living beings.

For example, arguments (incorrect ones, by the way) are often made that humans are “meant to be” vegetarians since we don’t have developed canines, an argument of course made preposterous when one runs through the list of mammalian omnivores which also do not have canines. Worse yet, the argument fails to recognize one of humanities greatest adaptations, which is that we can eat just about anything and survive on little for extended periods of time, a skill that allowed us to rapidly move out of East Africa into every corner of the globe.

More salient, however, is that humans were not “meant to be” anything. Like all living beings, we move in response to environment pressures and then adapt while suffering the devastating loss of infants who will not live to pass on traits unsuited to the current environment. Those babies better suited to make it to reproductive age pass on whatever it is that got them there to their children, who then pass it on to their own and mix with others in a sort of genetic democracy.

Babies of my ancestors in northern Europe were more likely to survive with lighter skin, while light skinned babies in Kenya were more likely to not. Neither is “better” than another, but both are suited to their respective environments as they are at that time and neither represent a terminus of genetics.

I take issue with a static view of the world, be it from fundamentalist Christians, who claim that humanity was created fully whole in God’s image or from well meaning secularists, who claim that the world was a biologically static place before the Egyptians, the Romans, the Europeans, the Capitalists and whoever else came in and fucked it all up. Really, it’s interesting how the Biblical creation story persists, even in secular debates.

In my own field, a great failing of research has been to ignore the dynamic nature or disease and human health, assuming that each cross sectionally measured point in time represents a final culmination of set of repeatable events akin to billiard balls on a table. Diseases aren’t that simple. They change in response to the challenges we present to them, which in turn feed back into our own behaviors.

I certainly don’t defend environmental degradation or would I ever minimize calls for developing more sustainable energy and food production systems. However, I would offer that the world, like human genetics is not static, but rather, incredibly dynamic and that a static (and somewhat falsely nostalgic) view of the world is destructive in itself because it keeps us from recognizing the challenges of the present day. Only by thoughtfully examining current conditions and recognizing that things can change can we develop solutions to present and potential future problems.

Alright, I’m done.

Thoughts on Environmentalism and an Anthrocentric World

Elephants in Laikipia

Elephants in Laikipia

My friend recently asked me if I thought that “humans were more important than other species.” I sent him back a rambling reply, the question was thought provoking to an extent that I turned it into a blog post, which, unfortunately, still rambles.

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).

Climbing on Things and Other Evolutionary Pursuits

KenyaRunnerI had one of those odd old man moments today where I’m watching a squirrel run up a tree. It goes half way up the tree in a split second, stops, then decides there’s nothing to run from after all. It then spends the next 10 seconds trying to get down. In short, the squirrel can climb a tree in a tenth the time it takes to get down. I realize this is a pretty silly observation.

Humans, too, are really good at running up hills, but terrible at getting down them. I remember climbing Mt. Mulanje in Malawi once. Going up was no problem at all. Getting down was dangerous as hell.

We pull better than we push, see right in front of ourselves better than beside ourselves, and have an easier time thinking of the concerns of a few proximal people, than a vast numbers of people who live far away. The latter, obviously, has important implications for global policy.

All of these things, though, are remnants of our evolutionary past and make complete sense when put in the context of our humble, though dangerous, beginnings. Arising in the savannahs of Kenya, humans would have been easy prey for all sorts of predators. When faced with a lion or hyena, a reasonable strategy is to run up the nearest tree and wait for the threat to pass. Thus, getting up the tree is critical for survival, particularly for children. Importantly, if they are eaten before they reproduce, the survival of the species is in question. Better climbers are survivors who are able to pass their climbing abilities on to their own children.

Getting down from the tree, of course, is not critical to survival. Thus, we can take our sweet time clumsily trying to get down, live and be able to pass our clumsy genes on to our children. So threats create effective adaptations and the lack of threat creates useless ones. The same is true for eyesight. Humans, as predatory omnivores, benefit from being able to focus on their prey while hunting, especially when they have the unique ability to run long distances while they wait for their prey (which likely has a serious head start) to tire out.

The Kericho region of Kenya is famous for producing long distance runners. I wonder if they maintained a particular hunting strategy that the Europeans or Asians no longer required.

Of interest to me is why humans might be so clan centric. It has been shown that humans are able to feel empathy for individuals close to them, but have a hard time imagining the sufferings of millions of unfamiliar people. This limitation, of course, allows us to wage wars far from home, and maintain indifference toward the millions living in poverty around the world.

Again, there are evolutionary roots here. Humans, being pack animals are adapted to be concerned about their immediately family and pack members, particularly children. This is important to survival. When any member of the group is threatened, all must be ready to ward off the threat, and protect children, who pass on similar traits to their children. A group of people indifferent to those aorund them would die out quickly. We are poor fighters on our own.

We have lived only in small groups until very recently. Thus, we never formed a need to be concerned with anyone else besides those closest to us. This state of having to care about the welfare of millions (or billions) is entirely new. We haven’t yet adjusted to it, though we make noble attempts. It is possible that we may never fully develop the ability to feel the pain of billions, unless something comes along and starts wiping out those who don’t. If that happened, we’d probably all be dead, though.

I had never thought of the problems of global policy in terms of evolutionary behavior. I guess, I have the squirrel to thank.

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