Mutualism all around us

After decades of teaching, writing, and reading about ecology and evolution I thought I had heard everything. But just recently I ran across an example of mutualism that surprised me.

Most vertebrates have lots and lots of parasites inside and outside of our bodies. Birds are no exception. They have it worse than humans because, unlike us, they cannot bathe away the oils, dirt, and parasites that accumulate on their skin, well protected as it is by feathers that are really good at repelling water.

But there are some things that birds do to reduce their parasite loads, besides preening with their beaks. They can expose themselves to environmental chemicals which may kill the parasites.

One example of an environmental chemical is smoke. Many naturalists have observed that birds will gather near a fire and extend their wings, allowing the smoke to get into their feathers. The smoke contains some chemicals that might help to reduce the growth of the parasites.

Another example, which I just read about, is that birds (in this case, a Eurasian jay) can stand near the entrance to an ant’s nest. They extend their wings, thus scaring the soldier ants that guard the entrance. The soldier ants squirt streams of formic acid at the birds, which does not harm them, but may reduce their parasite load.

Notice that this particular ecological interaction does not require that either the birds or the ants know what is happening. Natural and cultural selection reinforce the behavior, not the understanding.

Lucky to Be in Tulsa: The Twelfth Message from Fluff the Cottonwood Tree

 

I am happy that Stan has stayed in touch with me after he moved to France. He was glad to leave Tulsa, but I, speaking as a member of the species Populus deltoides, am lucky to be an American.

Almost everywhere in the world, mistletoes are parasitic. In Oklahoma, they grow mostly on elm trees, which are weakened by the Dutch Elm Disease. But in Europe, the elm trees (les ormes, Stan calls them) are stronger, and most of the mistletoes (gui, they are called) grow on black poplar trees (peupliers noirs, or Populus nigra). European black poplars are nearly identical to American cottonwoods, as I noted in my previous essay. If I had been a European cottonwood instead of an American, I would be loaded down with mistletoes. This photo that Stan took in December shows a typical black poplar.

European plant species are similar to, but usually not the same as, American plant species. But the ecological relationships—in this case, parasitism—do not always line up the same way. Evolution has played out along a slightly different path in Europe. Both America and Europe have elms, mistletoes, and cottonwoods, but in Europe it is the cottonwoods, more even than the elms, that are heavy with mistletoes. And in this one case, it has been good luck for me, an American cottonwood.

We Can Do It but We Won't

I am talking about lifting the masses of the world’s poor out of desperation and into a decent life. We can do it. It is autocatalytic: once some people have begun to rise, they can assist us in lifting others. This is already happening in some places where it has been encouraged, places in which the rich overlords have not prevented it. Humankind can rise if it is not oppressed. The Old Testament prophets railed against those who would grind the face of the poor into the dust. This is why they are poor: it is not because they are lazy, but because rich people oppress them. (There are, of course, a few lazy ones, but this is not usually the case.)

One of the most pressing needs is to control diseases such as malaria and intestinal diseases. These diseases thrive in, and reinforce, a spiral of poverty. Poor people with diseases cannot afford medical care, not even in America, and this only allows the diseases to spread more. The economic burden is multidimensional.

• First, there is the cost of the medical care itself.
• Second, there is the cost of people not being able to work. This is a cost to all of society, not just to the direct victim.
• Third, the parasites themselves, living in people with chronic diseases, consume a lot of the nutrients in the food that the people eat. If someone is full of worms, like the dissident who escaped from North Korea a couple of weeks ago, the worms are using up calories and nutrients.
• Fourth, and this is one I never thought of until I read about it in something that Lewis Thomas wrote, is that the food that feeds the parasites represents a substantial portion of the agricultural output of any nation that has a lot of poor sick people. Lewis Thomas said that fully twenty percent of the food produced by countries with chronic malaria goes to feed the malaria parasites.

The spiral of sickness in poor societies is reinforced by all four of the above forces. To help poor people escape from sickness, especially the mild chronic sicknesses that do not kill them but keep them torpid all of their lives, will help their lives not only directly, but indirectly by improving the entire economy of their nations.

For nations as for individuals, health is a good investment. Will we help poor countries to achieve this investment?

Lewis Thomas said, “The idea that all men and women are brothers and sisters is not a transient cultural notion, not a slogan made up to make us feel warm and comfortable inside. It is a biological imperative.”

The Red Queen Strikes

Lewis Carroll’s Alice encountered the Red Queen, who had to keep running just to stay in place as the world around her kept moving. Many evolutionary biologists, starting with Leigh Van Valen, used this imagery to describe how populations have to keep evolving just to stay where they are. The reason is that their biological environments keep changing. So if you can imagine a population of animals perfectly adapted to their physical environment, they must keep evolving new defenses against parasites. The parasites, being primarily small organisms with rapid life cycles, can evolve faster than most of their hosts. Confirmation has come from the fact that populations of animals such as snails that encounter more parasites are more likely to have sexual reproduction than populations with fewer parasites, which might reproduce without sexual recombination.

We live in a social environment with its own, and rapidly accelerating, version of the Red Queen. We are constantly evolving (by memes, not genes) new technologies that allow faster information transfer and processing, better medicine, etc. But even if we choose to remain in place—if we decide that what we have is good enough—we cannot do so, because our social environment is full of rapidly evolving parasites. Parasites in cyberspace continually evolve new ways to steal our personal information. Even corporations that consider themselves legitimate are always coming up with new plasmids in the fine print that allow them to charge us extra fees, or new designs that promote built-in obsolescence, or new attractions that make us think that we want their products when, honestly, we do not. You want to buy whole wheat bread because it is healthier? Better check to see just how much whole wheat is in it; the dark color may mostly be caramel. You have to be careful when you run your free AVG virus-check on your computer, because it will automatically sign you up for “protection” that is not free unless you take the initiative to uncheck the box. An anti-virus virus, as it were. You have to be careful when you go to a medical provider. No matter how small your problem, the provider may try to prescribe for you an expensive course of therapy.

Our economy is a jungle of parasitic perils. We have to watch every transaction, every account, all the time to catch entities that accidentally-on-purpose take money from us. Durant City Utilities charged me an extra $100 for water I did not use. I pay these utilities by automatic debit, and had I not scrutinized every transaction, I might never have caught their error, an error they admitted once I pointed it out to them. No matter what I do or don’t do, no matter how much stasis I may choose in my life, the economic environment is coming up with new ways to parasitize me. And you. No wonder it’s hard to get work done; we have to spend our time being paranoid about economic parasites. It’s sort of like a war.

What can we do, not just to protect ourselves but to go to war against the threats we face? I suggest we take stock of our strengths and opportunities, and use them. You may have more power than you realize. One thing we can do is to write letters to corporations and tell them that we know what they are doing to victimize us. In some cases, we can make them take notice. When I sent a nasty note to AIG, back when they were getting government bailout money while paying millions of dollars to their executives, they undoubtedly ignored it. But if I write a letter to a tobacco corporation saying that I teach hundreds of students not only about the dangers of tobacco but also about the illegal tactics that these corporations use (including their 1994 perjury to a House committee), they might take notice. They might take even more notice if I share contact information with my students so they can write letters too. Better yet, I can offer extra credit to the students. Or I can write and encourage others to write to sugar corporations about their deceptive marketing of a product that is dangerous in the excessive uses that they promote. We can, you see, go to war with them in the marketplace of ideas and consumer spending.

The marketplace is also filled with a cultural version of mindless parasites. The “people” with whom you interact may not even be people. When I first opened a Twitter account, I immediately had two followers whom I did not know, who had female names but no bios, and photos without faces (just alluring body parts). They soon disappeared. They were probably “bots” rather than actual people. And every writer has probably had some version of the experience I am about to relate. I sent a query letter to an agency listed in Writers Digest, but which had no website. I got a response back from what sounded like a personable agent saying, your project sounds interesting, send us the first couple of chapters. I emailed back, requesting further information about the agency. In response, I got exactly the same email as before. It appears, based on the online comments of other authors, that this agency is just a front for a law firm that thinks authors will pay them to represent their work to editors whom the author must contact. I wonder how many “literary agents” actually do not exist.

It would be nice if we could leave our parasites behind the way rotifers do, by just drying up and blowing away in the wind, leaving our fungi behind. But for us to survive in a Red Queen world of corporate parasites, we need to be constantly vigilant (trying not to slip into paranoia). We also need to fight back.