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roundtable:a modern mass extinction Watch Show 3:
"Extinction!" on PBS
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First, a general question. Are we now in a mass extinction, and if so, why does it matter?
Some Web visitors wrote to say they have heard it said, especially of tropical and marine organisms, that we are losing species before we even know of them. And the question is, if we haven't discovered a species yet, how do we know that we've lost it?
Would Darwin support the Federal Endangered Species Act? Millions of dollars are spent by corporations and government for habitat conservation plans, recovery plans, etc., for species that seem doomed for extinction. Is this a wise use of money? Why or why not?
If extinction and mass extinctions are a natural part of Earth's history, should we really be concerned about our effects on endangered species? Are we trying to fight something that's inevitable anyway and that is much larger than us, as a single species ourselves?
I'm concerned with the loss of genetic diversity because it affects food supply, drug discoveries, and the stability of ecosystems on which we depend. And yet, I'm very skeptical of the theory of evolution as it now stands. How does the theory of evolution -- or we could also say that as evolutionary thought -- explain and predict what's going on with the current cycle of extinction, better than if we had to just rely on what we can observe? In other words, what context and what value does evolutionary thought provide to this discussion that we're having?
Several other questions relate to this: Loss of biodiversity, water and air pollution, and the greenhouse effect are all impacting the biosphere, and if these are indeed combining to produce a mass extinction, do you think our species will survive it? Peter's already said that he thinks yes. How about some other perspectives?
Let's move onto some more specific questions. Why do bigger species go extinct faster than smaller ones?
Do you feel that extinctions of large Ice Age mammals had any human causes?
Another Web user wrote: I know there is a gene databank under construction right now. Could this be used as a modern Noah's Ark for the future?
We'll wrap up with a different kind of question. There was one that came from a younger visitor to the Web site who asked, What can kids do to help save the rain forest and animals?
   

 

Q: Several other questions relate to this: Loss of biodiversity, water and air pollution, and the greenhouse effect are all impacting the biosphere, and if these are indeed combining to produce a mass extinction, do you think our species will survive it? Peter's already said that he thinks yes. How about some other perspectives?
Panelist Responses: < back to intro page
Tundi Agardi
I think maybe a better question would be how will our species survive. And I think I would agree with Peter, that we're likely to survive massive changes in the biosphere, including some of the very scary predictions that are made by global climate change modelers, who are talking about pretty severe and very large, geographically large-scale changes, to things like ocean circulation and so forth.

I think we will survive it, but I think the better question would be: How will we survive in terms of what will the quality of life be like? And also, a question that I would pose to the rest of the panel, [who are] more suited to address the question, is this: How will a biotically impoverished world be able to deal with any kind of catastrophic impact that might arise in the future, such as another set of volcanic events or some kind of a collision with an asteroid, or any of these things that we think have caused mass extinctions in the past?

Is the biotically impoverished world that we're headed toward [one] that's going to be less able to deal successfully with the kinds of catastrophes that we've seen in the past?

So, I think there are two issues. One is, it's not just whether we'll survive, but how will we survive, and with a quality of life that anybody will think is worth living. And secondly, are we dooming ourselves, ultimately, in light of the fact that there are very large-scale environmental, meteorological, and so forth, things that we could be faced with in the future.
Ariel Lugo
I'll say that, yes, humans will survive, but that's as long as we have energy and natural resources to power our human existence. And so the question of quality of life -- I guess it depends what your expectations are, because as you know, there's a huge range of life quality in the world right now, that creates trouble for international affairs. But right now, humans will be limited by fossil fuels, and, unless we find a new energy source, energy will take care of how far humans can go.

As far as how an impoverished world will take up a cataclysmic event, on this island, here in Puerto Rico, we experience hurricanes, and we look very closely at how our forests survive hurricanes. And one thing we found out is that, fundamentally, this island, the forests of Puerto Rico, are responding to human effects more than they are to hurricanes. Hurricanes establish more or less the base condition, to which all the flora and fauna have to be adapted. But you can pass three or four hurricanes over a piece of forest and you cannot erase the human imprint that was established, say, 100 years ago or 200 years ago.

So I think that the survival of ecosystems to catastrophes is an inherent function of the organisms that are present, whether they have or have not been impacted by humans.

But the human ability to maintain its activities is a function of its capacity to harness resources, and eventually we're going to be limited by resources. That's where nature, then, resets the balance.
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