Search This Blog

Thursday, May 19, 2011

Lost in Space?

I was scanning the pages of a scientific journal one evening and fell upon a guest editorial that made me fall out of my chair. Two scientists from a respectable institution suggested, with all apparent sincerity, that the best way to avoid the extinction of humanity would be to colonize outer space. 

This immediately brought to my mind the image of the interstellar community frantically deploying some kind of cosmic germ killer to deal with the infectious blob spinning off from our mortally wounded biosphere.  What have we done here to deserve welcome anywhere out there?  Our record of stewardship is not good.  We have not been kind to any life forms that have had the misfortune to be present when we have colonized new territory- not even members of our own species.  Those of us left behind could only hope that any life forms out there would not have a view of epidemiology that included going after the source of the incipient infection.

Venus bus probes, image from NASA.

 

Humor aside, there are some very troubling aspects to this argument.  I was surprised and disappointed that such a view could be espoused in an ecological journal.  Ecologists, of all people, should appreciate the intricate, invisible bonds that tie us to the biosphere of this planet.  The history of the evolution of this biosphere is inseparably bound within us, from the micro nutrients we need, our bodies' metabolism, and the bacteria that live in our digestive systems to our circadian rhythms, set by the sun as we move around it with our planet Earth.  We have proven we can survive, briefly, out of the context of our world, but do we really have the arrogance and hubris to believe we can recreate everything we need somewhere else, when we have only the shallowest understanding of the interrelationships here that sustain us?  Ecologists should know better.

Home Sweet Home
View of Earth from Apollo 17. Image from NASA

There are even more disturbing aspects to this argument.  Who's going to get to go? There are nearly seven billion people here.  Do we really think there can be a morally justifiable process to pick those few?  What traits would we choose?  There is a saying regarding China- if your talents make you one in a million, there are ten thousand people just like you. That would mean seventy thousand just like you throughout the world. Are we willing to deliberately condemn most people to linger on a dying planet while we pour the last of our scarce resources into flinging those few into space?  How could those few live with that decision?  Even worse, what if they could? What would that say about the values and ethics that we chose to propagate beyond our planet's boundaries?

It would take a tremendous investment of resources, including non-renewable ones, in order to succeed.  Even if we decide that we do not care about the moral implications of allowing billions of individuals of our own species, not to mention all the rest of the life forms, to suffer slow death on a ruined planet, why do we think those condemned masses would allow the chosen few to despoil the remaining resources of the planet in order to make their getaway?  And again, the fact that a few might be willing to ruin the futures of so many also says nothing good about the values and attitudes we would be broadcasting into the cosmos.

Unfortunately, this really isn't a hypothetical situation.  There are a chosen few who are already busy destroying the futures of the many, apparently without a single second ethical thought.  Our goal is not to colonize the final frontier, but simply to espouse a lifestyle that happens to extend far beyond our ecological means.  Ironically, it is a lifestyle that frequently leaves us frenetic, sick, and miserable in addition to creating a tremendous delayed cost that our children will have to bear.  The chemistry of our atmosphere, oceans, and even the soils are changing rapidly.  They are not changing in ways that will enhance our survival.  It is sad indeed that ecologists are not at the forefront of sounding the warning, and leading the way in reinventing our society so that we are not committing an act of genocide whose victims will include all of us and our children.

View of Earth from the moon. Image from NASA.

I can imagine that little space capsule spinning out of the Earth's orbit, carrying the seed of incipient disaster to new worlds blissfully ignorant of the fate that awaits them. Out the little window, a message forms in the clouds over the small planet they leave behind:

Do not enter. Toxic dead zone.

Surely we can do better than that.

Friday, May 6, 2011

Swallows

The violet-green swallows are back, wheeling under lowering clouds threatening more winter rain, even though the pasture grass is greening up and the spring wildflowers are defiantly blooming.  These plants are not pollinated by honeybees, but rather by beetles, bumblebees, and other animals less prone to an unusually cold, late spring.
Violet-green swallow, Tachycineta thalassina. Photo by Tom Munson

The swallows are back.  Their internal drives told them to head north into the teeth of cold wind, rain, and hail.  The day I first saw them this year was hardly in the mid-40s, with a sharp-tongued wind laying bare the fragile promise of my jacket.  I wondered if there were any airborne insects for the birds, between the cold and that wind.

These birds spend the northern hemisphere winter in South America, a long way away. They make their way there and back again on those marvelous, fragile wings, guided by the shared hertitage twisted into the strands of their DNA.  We call it instinct, which means we don’t know how they know.  At leas, it doesn’t appear to be knowledge acquired only through the individual’s own experience.

Animal navigation has been the subject of a great deal of human curiosity and research, and we are slowly making headway in understanding the cues that animals use when traveling over vast differences.  Recent work with loggerhead sea turtle hatchlings suggest that the hatchlings use magnetic forces in the earth to find their way, both with respect to latitude, their north-south position, and longitude, their east-west position.  The magnetic field isn’t consistent particularly on the east-west gradient, but the variation through space may be sufficient for the hatchling turtles to recognize their position and make their huge circuit of the Sargasso Sea. 

Loggerhead sea turtle, Caretta caretta. Photo credit: NOAA

Birds also use magnetic cues to find their way.  However, their ability to navigate is also clearly influenced by their experience.  When a biologist captured and transported south-bound starlings en route from northern Europe in the Netherlands and released them in Switzerland, the adult birds compensated for the sideways shift, but the young birds did not.  Juvenile barn swallows responded to magnetic cues when skies were overcast, but didn't do so otherwise. Different birds use different methods of migration, a result of the behavior having evolved again and again. Landmarks and stars and the sun all are used to some extent.  Migrating birds travel enormous distances and risk death if they arrive in the wrong place.  No wonder they draw their navigational information from many sources.

The feat is perhaps all the more spectacular for braiding together multiple lines of evidence, experience, and instinct in a brain we are more likely to mock than admire.  However they do it, I’m glad the swallows found their way back to our pastures again.  Their astonishing flight seems more an aerial celebration than simply a means of survival.