Archive for the ‘Science’ Category

Our emerging, evolving new wildlife

August 19, 2014
Coy Wolf

Coy Wolf

For years I’ve been hearing reports of “coy wolves” in upstate New York—crossbreeds with the cunning of a coyote and the ferocity of a timber wolf.

The other day my friend Anne Tanner e-mailed me a link to a New York Times article that reports not only on coy wolves, but other kinds of new hybrid wildlife—for example, hybrids of polar bears and grizzly bears, known as grolar or pizzly bears.

And the coy wolves come in many different varieties, based on combinations not only of coyote and wolf genes, but also dog genes.

The writer gives many other examples of animal hybrids (the Canadian lynx with the American bobcat) but none so remarkable as the pizzly bear or coy wolf.

They are the result of changes in the natural environment caused by human action, driving or pulling animals out of their long-established territories and bringing previously separated species together.

Biologists once regarded hybridization as an evolutionary dead end.  Now they see it as one more way that living things adapt to a changing environment.

Maybe a thousand years from now, when World Wars One and Two are only remembered by specialists, historians will regard the emergence of new hybrid species as the signature event of the 20th century.

Two physicists go for a drive …

August 2, 2014

heisenberg&schrodinger_n (more…)

Denial won’t stop the world from getting hotter

July 28, 2014

hottestJune

If you want to understand how things are changing, you should not be content with comparing the current month or year with the previous month.  You should look at the data as far back in time as it goes.

The data on global warming and climate change shows ups and downs, but a long-range trend toward a hotter planet.  You could argue (although I don’t) that the change is due to a mysterious X factor rather than human-caused greenhouse gasses.   I don’t think any rational person can argue against the reality of the change.

That’s why it is important to prepare for the change, and that’s why it’s crazy for Republican congressman to try to forbid government agencies to take the long-range trend into account.

Here is one way the two political parties differ.  Most Democrats are willing to at least acknowledge that global climate change exists and will have consequences.  The dominant group in the Republican Party is unwilling to do even that much.

I think it was the SF writer Philip K. Dick who said that reality is that which exists whether you believe in it or not.  The global warming trend is real, whether you believe it or not.

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The human body and its invisible defenders

July 12, 2014

Hat tip to Jack Clontz and his friend Marty.

The human body and its invisible tenants

July 12, 2014

There are more bacteria in the human body than there are human cells.

Hat tip to Jack Clontz and his friend Marty.

The complete real estate of the Solar System

July 7, 2014

Randall Munroe shows the surface area of the planets and asteroids in the Solar System that are hard enough to walk on.   Jupiter, Saturn, Neptune and Uranus don’t count because they don’t have solid surfaces.  If they did, their surfaces would be many times bigger than that whole map.

via xkcd.    Hat tip to kottke.org.

Brainwashing and mind control are possible

June 4, 2014

Elizabeth Loftus, the psychologist and memory researcher, has documented a disquieting success in implanting false memories by simply suggesting to a subject that he has experienced a fictitious event.

Such pseudo-events, invented by psychologists, may vary from mildly upsetting or comic incidents that, for example, as a child, one was lost in a mall to more serious incidents that one was the victim of a serious animal attack, or a serious assault by another child.

After initial skepticism “I was never lost in a shopping mall”, and then uncertainty, the subject may move to a conviction so profound that he will continue to insist on the truth of the implanted memory, even after the experimenter confesses that it never happened in the first place.

via Oliver Sacks | The New York Review of Books.

It is possible to remember things that never happened.   It is possible for a skilled psychiatric professional to implant false memories in people.

And now research with rats indicates that it is possible to work on the brain so as to delete—and restore—memories by physical means (but so far only in rats).

As an old guy who is starting to suffer from loss of memory, and whose greatest fear is dementia or Alzheimer’s disease, I think research on memory is a good thing, not a bad thing.

But a world in which memory deletion, memory activation and memory falsification were understood is a science-fiction dystopia.  It means that it is technically possible for a future government to exercise totalitarian control over the individual to an extent that Hitler, Stalin and Mao only dreamed of doing.

These far outweigh the possible benefits of these techniques, such as in treating post-traumatic stress syndrome.  And even there, I expect that, just as with psychiatric drugs, many therapists would use memory deletion techniques without fully understanding their limitations and wider effects.

LINKS

How to erase a memory—and restore it: Researchers activate memories in rats in Science Daily.  Hat tip to naked capitalism.

Speak, Memory by Oliver Sacks in the New York Review of Books.  A report on false memories.

How Memory Speaks by Jerome Groopman in the New York Review of Books.  A review of research on the neurological basis of memory.

Johnny Mnemonic by William Gibson.  Science fiction.

Carl Sagan’s baloney detection checklist

May 29, 2014
  1. Wherever possible there must be independent confirmation of the “facts.”
  2. Encourage substantive debate on the evidence by knowledgeable proponents of all points of view.
  3. Arguments from authority carry little weight — “authorities” have made mistakes in the past.  They will do so again in the future.  Perhaps a better way to say it is that in science there are no authorities; at most, there are experts.
  4. Carl_Sagan_by_Takes2ToTricycleSpin more than one hypothesis.  If there’s something to be explained, think of all the different ways in which it could be explained.  Then think of tests by which you might systematically disprove each of the alternatives.  What survives, the hypothesis that resists disproof in this Darwinian selection among “multiple working hypotheses,” has a much better chance of being the right answer than if you had simply run with the first idea that caught your fancy.
  5. Try not to get overly attached to a hypothesis just because it’s yours.  It’s only a way station in the pursuit of knowledge.  Ask yourself why you like the idea.  Compare it fairly with the alternatives.  See if you can find reasons for rejecting it.  If you don’t, others will.
  6. Quantify.  If whatever it is you’re explaining has some measure, some numerical quantity attached to it, you’ll be much better able to discriminate among competing hypotheses.  What is vague and qualitative is open to many explanations.  Of course there are truths to be sought in the many qualitative issues we are obliged to confront, but finding them is more challenging.
  7. If there’s a chain of argument, every link in the chain must work (including the premise) — not just most of them.
  8. Occam’s Razor.  This convenient rule-of-thumb urges us when faced with two hypotheses that explain the data equally well to choose the simpler.
  9. Always ask whether the hypothesis can be, at least in principle, falsified.  Propositions that are untestable, unfalsifiable are not worth much.  Consider the grand idea that our Universe and everything in it is just an elementary particle — an electron, say — in a much bigger Cosmos.  But if we can never acquire information from outside our Universe, is not the idea incapable of disproof?   You must be able to check assertions out.
  10. Inveterate skeptics must be given the chance to follow your reasoning, to duplicate your experiments and see if they get the same result.

via Brain Pickings.   Hat tip to Barry Ritholtz.

Click on Who Was Carl Sagan? for more about him.

When oceans rise, I’ll be gone, you’ll be gone

May 14, 2014
West Antarctic shown in red.  Source: The Guardian

West Antarctic shown in red. Source: The Guardian

Two separate groups of climate scientists have concluded that the West Antarctic ice sheet is in the process of collapsing, and that this process is inevitable.  The result will be that the sea level will rise at least four feet, and maybe as much as 12 feet, putting Houston, New Orleans, Miami, New York City, Boston and other coastal cities under water.

But don’t worry!  The scientists say this is a slow process that won’t end during the lifetime of anybody now alive.

So how much should we worry?  How much should we worry about the whole question of climate change? [1]   The world’s weather is changing, and long-term global temperatures are rising, but this is the result of things that were done or not done in previous generations.  Nothing that we do to reduce greenhouse gas emissions and mitigate climate change will change this.  It will only make things less bad for future generations.

How much do we owe future generations?  The 18th century statesman Edmund Burke said we owe them a lot.  He said society is a compact between past generations, the living and generations yet to come.   We owe future generations at least as good a world as past generations passed on to us.

Some modern economists so we owe future generations little or nothing.  They make economic calculations based on future benefits being less valuable than present benefits, based on a yearly discount equal to the prevailing rate of interest.  Based on this method, the value of anything diminishes rapidly, and the value even of saving the world is very little after a century or so.

There’s a more sophisticated economic argument that says that future generations will be wealthier and more technologically advanced than we are, so why should we sacrifice to help people who will be better off than we are?  And, after all, can we really know what the priorities of future generations will be?

When I first heard of global climate change, back in the 1970s, I had my doubts as to whether it was real.  But I still thought it was a good idea to reduce automobile and smokestack emissions and develop solar and wind energy because these things are good in themselves and, if global warming was real, so much the better.

I no longer doubt the reality of global climate change, but I no longer think it is possible to seriously mitigate it without reducing the American material standard of living and setting limits on everybody else’s standard of living.   I am not so noble that I would unilaterally give up the benefits of, say, airplane travel unless everybody else did, and I don’t think this will happen until there is no other choice.

Present-day Americans have little sense either of the past or of the future. [2]  In addition, it would be hard to ask Americans to sign up for unshared sacrifice when, for the past 20 or 30 years, the majority of Americans have undergone unshared sacrifice.  Nor is it reasonable to expert the people of China and India, who between them comprise nearly half the world’s people, to give up their future hopes unless North Americans and western Europeans reduce our material standard to meet theirs.

I respect my friends in the Sierra Club and other groups who are campaigning to reduce greenhouse gas emissions.  I think what they are doing makes sense, even though I also think what they are doing is unlikely to succeed.  How about you?  What do you think?

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The life cycle of mountains

May 11, 2014

Hat tip to kottke.org.


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