2009
The End of Altruism
Apr. 16, 2009
Evolution is not “survival of the fittest.” Preachers like to portray evolution as bloody and merciless, favoring the powerful and violent animals over the weak and benign. But this picture is incorrect. Although evolution sometimes produces violence, it more often produces altruism in the world of animals. Altruism is when one animal is nice to another animal of the same species.
Evolution produces altruism in three ways. First, natural selection favors animals that help their close relatives to reproduce—for in this way, the animal can indirectly pass its genes into the next generation. The love of parents for children is biological, and is found in birds and mice as well as in humans. Second, natural selection favors direct reciprocity, in which an animal does something nice for another animal, in anticipation of getting the favor returned in the future. Third, natural selection favors indirect reciprocity, in which an animal (always a human animal, as far as we know) does something nice for another animal that cannot possibly ever return the favor—and thereby receives greater social status and esteem. We admire rich, generous donors. Animals—especially human animals—invest in “social capital”: having friends and admirers is usually better than having money in the bank.
Altruism was perhaps the most important process in human evolution. Our species existed as tribes. These tribes usually fought one another, but within each tribe there was a lot of altruism. The chief of the tribe enjoyed some benefits not available to other tribal members, but was not much richer than they, and did not enslave them or take all of their resources away from them. The primary reason they did not do this is because they would have to look their fellow tribesmen in the eye while doing it.
But with the beginning of civilization, altruism began to fall apart. Kings could enslave poor people or take all of their riches away from them. In a large city-state or empire, the king could hide in his throne-room and did not have to look his victims in the eye. Democracy began partly as a way of destroying the power of kings to do this. Today, very few kings remain and those few are primarily ornamental. Dictators may briefly get away with such behavior. But right here in the United States, rich people are able to oppress poor people in a way not very different from the way kings treated their slaves. Rich people today can take the life savings away from their victims while hiding in boardrooms and mansions, just as kings could hide in their palaces.
If only the rich people who caused the financial crisis in America, and which has spread around the world, could be made to look their victims in the eye! Maybe then they would be unable to walk off with millions of dollars of money from the federal government and from their investors, and altruism would return to our society.
A Lovers’ Embrace?
Apr. 26, 2009
Richard Dawkins visited the University of Oklahoma on March 6, 2009. In the parking lot outside of the field house where he spoke, a van was parked. It was a van for the Thank God For Evolution group (see evolution photos). In the logo on the side of the van, a Jesus fish, an extremely common symbol on bumper stickers, was kissing a Darwin fish.
While this sentiment is commendable—who would not want to minimize the unnecessary conflict between evolutionary science and religious objections to it?—it is misleading. It creates the appearance but does not deliver the substance of resolving a conflict.
First, evolution is a science and religion is religion. They do not have the same objectives. Evolutionary science can help to explain the origin of religion and of religions, and science can test religious claims. But science cannot determine which ethical beliefs are right.
Second, a major contradiction remains between evolutionary science and Christianity, no matter which interpretation is used. Evolution is based on natural selection, which is a ruthless, merciless, and often arbitrary process. The losers in the evolutionary struggle may have inferior genes, through no fault of their own; or may simply be experiencing bad luck. And the deaths of the losers in the evolutionary arena are often grisly and painful. How could a God of love and compassion, a God who rewards goodness, use such a process as a method of creation? Nature, in its daily operation as well as its evolutionary history, presents a picture of its creator (or its creative process) that starkly contradicts the Biblical God.
A few years ago, I wrote a book manuscript in which I attempted such a resolution between evolutionary science and Christian belief. (Interestingly, I entitled it “Thank God For Evolution,” the same title that was used more recently by a book that apparently inspired the organization that sponsored the van.) Even Niles Eldredge thought it would be a good book, and told me so. My agent, however, was not interested in it, and in hindsight this was a wise decision for which I am grateful. If I had published this book, I would now be a little bit embarrassed of it, mostly due to its projection of certainty. At the time, I thought I had resolved the conflict; now I know that probably nobody can do so. In that manuscript, I spoke confidently about God, as if anybody could know who or what God is.
The best we can do is to admit the truth and the consequences of evolutionary science; to admit that we cannot define our religious terms; and to make our best efforts to decide for ourselves the ethical principles by which we, and the world, should live. Even an atheist can do this. Atheism does not lead to a rejection of ethics and a pursuit of brutal selfishness. Somebody asked Richard Dawkins (the world’s most famous atheist) if he thought there was any basis for ethical beliefs. While he did not believe there were any transcendent truths, he did note that, all around the world, an ethical consensus is arising: despite ethnic and religious differences, people of many nations now understand that war and oppression and the abuse of the Earth are wrong. It is hard to pinpoint the sources of this ethical consensus, but there it is, and we can believe in it.
We Can Afford Environmental Protection
May 12, 2009
They say we cannot afford environmental protection. Not now, during the economic downturn.
But as I explain in the recently-released Green Planet: How Plants Keep the Earth Alive, we cannot afford to lose the benefits that the natural world--especially plants--provides to us. Economist Robert Costanza estimated that natural ecosystems provide $33 trillion (that's right, trillion) of free services to the world economy. In my book, I explain what many of those services are. Natural ecosystems such as forests and grasslands put oxygen in the air, remove carbon dioxide from the air, create cool shade, prevent floods and droughts, produce food, create soil, create habitats and heal them from disturbances. The cost of doing all of these things for ourselves without the help of plants is not quite incalculable, but pretty close to it.
Forests and grasslands are more valuable to us just as they are than they would ever be if converted into commercial products or real estate. The trees and grasses are even more valuable to us than the wild animals that we love so much. For, it must be admitted, deer and bears are pretty much like us--they eat food, breathe in oxygen, and breathe out carbon dioxide. But plants are the counterpoint of renewal to our animal activities: they make food from sunlight, produce oxygen, and absorb carbon dioxide. They run on solar energy and reproduce themselves. They do everything in complete silence and unutterable beauty. We do not need to pay them or even to thank them, just give them a chance to live. They are not doing this for us, but as their own way of making a living. But by pursuing their own lives, they create life for us.
Plants cannot save the world all by themselves. We are producing too much carbon dioxide for them to absorb even under the best conditions. And the conditions are not best: warmer and drier conditions will make it harder for plants to grow. At the same time that we need them the most we are destroying them. As I argue in the closing chapter of my book, we need to live frugally, creating as small of a carbon footprint as possible-perhaps one small enough that plants can, in fact, erase it. A greenhouse disaster is now inevitable, because the carbon dioxide that is in the air already has yet to absorb all of the heat of which it is capable. But perhaps there is still time to minimize the disaster.
This essay is also posted on the science blog for Rutgers University Press, reprinted with permission.
Dividing Up the World
May 30, 2009
Nobody knows how many species there are in the world. There may be 10 million species, perhaps even more, depending on how “species” is defined for bacteria. And certainly nobody knows why there are so many.
The cartoon version of evolution would lead one to believe that there should not be very many species. Survival of the fittest should lead to a few tree species shading out the others, and a few animal species literally beating out the others. And just how many different ways are there to be a decomposer living down in the soil? If only “the best” species survive in any one location, why is there such a huge number of species in any one place? And if most species are capable of dispersing widely to new locations, why are not these “best” species dominant over wide ranges? Some species, of course, are extremely abundant over wide regions of the Earth. But what about the others?
A walk in the woods in early springtime might provide some clues. When some friends and I recently did this on Turkey Mountain (the site of two previous essays), we paid attention to the trees and shrubs. The tree species divided up the mountain among themselves—some preferring the hot dry west slope, others the cool moist east slope. But they also divided up time. Post oaks and blackjack oaks both prefer the dry side of the mountain, but the blackjacks grow more quickly and die sooner in sites with more disturbance. The blackjacks also open their buds and release pollen into the wind a little sooner; by the time the post oaks release their pollen into the wind, the blackjacks may have mostly finished. The wild plums and their close relatives the black cherries had already opened their buds. The wild plums were in full bloom, while the buds of black cherries produced leaves. There are not a lot of pollinators in early spring—we saw black swallowtails, not much else—and the wild plums received their services. In a couple of weeks, it would be the turn of the black cherries to be pollinated. At one point on the trail, there is a little patch of poison ivy mixed with fragrant sumac. In summer, they look a lot alike—many people confuse them. They are close relatives, both in the cashew-mango family Anacardiaceae. Neither had opened their leaves. The fragrant sumac, however, had opened its flowers, inviting the few pollinators that were available. Poison ivy flowers open in early summer, after the shiny toxic leaves have expanded. Opening flowers early in the spring is a risk—on this warm sunny day, it worked, but sometimes the cold rain can last through most of the early spring and ruin any hopes of pollination success.
These plant species coexisted by dividing up space and time, specializing on their own geographies and schedules. The world can hold a lot of species, when these species avoid competition with one another, and each specializes on its own way of life. I do not mean to suggest that Nature has some mystical peaceful coexistence; the natural world is a capitalistic economy in which individual organisms more often succeed by specializing rather than fighting. The capitalism of Nature is succeeding while ours is failing precisely because our modern American capitalism models itself after the cartoon version of evolution rather than after the reality of what happens in the natural world. People are endlessly creative at finding ways of making a living without making a killing. The role of the government is to prevent the latter, thus permitting the former.
If Humans VanishedÖ
June 14, 2009
What would happen to the world if humans vanished from it?
Such a thing is very unlikely to happen. Humans are so numerous and so adaptable that there will probably be at least a few people on the Earth until the Sun enters its final throes of death. What is more likely to happen is that human civilization could collapse. Our modern economy and system of food production depend entirely upon fossil fuels and advanced technology. Even the availability of food does not guarantee survival, as was evidence during the Irish Potato Famine, when people starved because they could not buy the plentiful food in the marketplace. The human population of nearly seven billion cannot conceivably be supported by hunting and gathering, especially by a mob of hungry people pouring out of cities and towns. Even rural people survive on groceries. The few that are lucky enough to find wild hickory nuts (or to even know what they are) will discover that the shells are too hard to break except with a very large hammer. To survive by cracking hickory nuts uses more calories than the nuts would provide. The few naturalists who know that bramble shoots are edible would find them only in the spring. As soon as the ammunition ran out, few hunters would know what to do, aside from wrestling a few turtles. But even though the extinction of humans is extremely unlikely, such a disappearance is a useful scenario for understanding human impact upon the Earth.
Much of what humans have done to the Earth, for example our buildings and highways, would be quickly erased. Nearly all of the plants and animals that humans have bred as crops and livestock would quickly become extinct. They largely depend upon humans for their survival. Tomatoes, for example, cannot produce seeds unless humans keep their fruits from touching the ground and rotting. Ears of corn would sprout into a dense mass of seedlings, all of which would probably die. Poodles would die instantly. Humans have bred crops and livestock for purposes other than survival in the wild. Some livestock, pets, and plants would become feral, as has happened with horses, swine, cats, and kudzu. Pest animals and weeds have adapted to the conditions that humans have created. Some of them, such as rats, would continue to thrive. But as humans are the major source of ecological disturbances, the weeds and pests that live in such conditions would eventually become rare. The weeds that thrive in agricultural fields are generally not the same ones that colonize after disturbances, such as floods and fires, in the natural world. For example, the velvetleaf weed (Abutilon theophrasti), which today thrives in soybean fields and in recently abandoned farmland, would grow only occasionally on the banks of streams and lakes. The human contribution to biological diversity would vanish quickly. The new rulers of the Earth would be species that existed before humankind.
Human population collapse has occurred before. When Europeans introduced diseases such as smallpox to North American native populations, the germs spread faster than the Europeans, and annihilated up to 90 percent of the natives. At that time, population explosions of wild animal species occurred. Natives in the middle of North America had hunted bison and passenger pigeons; with the collapse of hunting, the pigeon and bison populations vastly increased. Natives in the southeastern part of North America had fished extensively; with their disappearance, populations of fish—and of alligators that ate them—exploded. This explains the observations of Europeans and Americans, such as botanist William Bartram, who marveled at the hundreds of alligators in every lake and river in Florida; and they assumed North America had always been this way. If humans vanished today, a similar phenomenon would probably not occur, since most sustenance comes from helpless livestock rather than wild game.
One human artifact would persist for millennia: the high levels of carbon dioxide in the atmosphere, contributing to a greenhouse effect. The Earth would be warmer for thousands of years because humans had been on it. However, this greenhouse effect would not be very devastating, except for tundra species whose habitat would vanish forever. The main reason that the greenhouse effect threatens biodiversity today is that humans have blocked the corridors of movement by which, in previous millennia, plants and animals have adjusted to global climate changes by migrating. With humans out of the way, global warming would probably cause even fewer extinctions than occurred at the end of the most recent Ice Age. Even coral reefs, already dying because carbon dioxide is acidifying ocean waters, would recuperate in a few hundred years after human disappearance.
Perhaps the human artifact that would persist the longest, for several million years, would be the toxins that industry manufactures. Heavy metals and persistent organic molecules already recycle through the food web over and over. And then there is plastic. Plastic is forever. No known natural process breaks it down. Save for a little bit of plastic destroyed during incineration, every bit of plastic ever manufactured still exists. Ultraviolet radiation and oxygen in the air can make it brittle, but it simply fractures into smaller and smaller pieces. This makes plastic trash even more dangerous. When the fragments are small, many animals consume it with the plankton that they normally eat. Natural selection has not produced seabirds that can distinguish between a fish and a floating piece of plastic. In some areas, each handful of sand is 20 percent plastic, and plastic fragments are up to six times as abundant as plankton. There are seven major gyres of ocean current that trap even large pieces of plastic into large, and almost permanent, garbage dumps. Long after the lights of the cities cease to be visible on the dark side of the Earth, long after the last reservoirs fill with silt and their rivers rush over the dams like natural waterfalls, and entropy has scrambled the last of the digital data, flakes of plastic will still be swirling through the ecosystems of the Earth.
