Galactic Baby Boom Influenced Life on Earth

Sara Goudarzi
Staff Writer
SPACE.com Mon Nov 27, 9:00 AM ET

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The stellar baby boom period of the Milky Way sparked a flowering and crashing of life here on Earth, a new study suggests.   

Some 2.4 billion years ago when the Milky Way started upping its star production, cosmic rays--high-speed atomic particles--started pouring onto our planet, causing instability within the living. Populations of bacteria and algae repeatedly soared and crashed in the oceans.

The researchers counted the amount of carbon-13 within sedimentary rocks, the most common rocks exposed on the Earth's surface. When algae and bacteria were growing in the oceans, they took in carbon-12, so the ocean had an abundance of carbon-13.

Many sea creatures use carbon-13 to make their shells. If there is a lot of carbon-13 stored in rocks, it means life, the origin of which is still unknown, was booming.  Therefore, variations in carbon-13 are a good indicator of the productivity of life on Earth.

The researchers found that the biggest fluctuation in productivity coincided with star formation, which had an affect on Earth's climate and therefore on the productivity of life on our planet.

According to one theory, when a star explodes far away in the Milky Way, cosmic rays penetrate through the Earth's atmosphere and produce ions and free electrons. The released electrons act as catalysts and accelerate the formation of small clusters of sulfuric acid and water molecules, the building blocks of clouds. Therefore, cosmic rays increase cloud cover on Earth, reflecting sunlight and keeping the planet relatively cool.

Although cold and icy times are generally considered unfriendly to life, the data reveals that biological productivity kept oscillating between very high and very low. The reason, the researchers suggest, is that stronger winds during icy epochs stirred the oceans and improved the supply of nutrients in the surface waters.

"The odds are 10,000-to-1 against this unexpected link between cosmic rays and the variable state of the biosphere being just a coincidence, and it offers a new perspective on the connection between the evolution of the Milky Way and the entire history of life over the last 4 billion years," said study author Henrik Svensmark of the Danish National Space Center.

The study was detailed in a recent issue of the journal Astronomische Nachrichten.

Family Walks on All Fours, May Offer Evolution Insight, Experts Say
James Owen in London
for National Geographic News
March 8, 2006

Five adult siblings who can walk only on all fours have been found in Turkey, researchers say. These human quadrupeds may provide clues to how humans evolved to stand on two feet.

The three sisters and two brothers may offer insight into the way our apelike ancestors moved, according to scientists. Human ancestors are believed to have begun walking on two legs more than three million years ago.

Photo: Kurdish family in Turkey walking on all fours

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    * Photo in the News: Earliest Known Human Ancestor
    * Did Climate Change Trigger Human Evolution?
    * Printable Map: Early Human Migration

(See "Fossil Pushes Upright Walking Back 2 Million Years, Study Says.")

Discovered in a remote area of southern Turkey last summer, the family of ethnic Kurds has sparked a scientific debate, which will be covered in a BBC television documentary that is set to air on March 17 in the United Kingdom. The family's exact location and last name have not been disclosed.

Born with a genetic brain abnormality, two of the sisters and one of the brothers are thought to have only walked on all fours their entire lives. The two other siblings can walk upright for short distances.

The siblings' parents are closely related and have had 19 children in all.

This bizarre case is not a hoax, according to experts who have studied the family.

The cause of the four-limbed locomotion, however, is a bone of contention among the researchers.

Uner Tan is a neurophysiologist—a doctor specializing in the functions of the brain, spinal cord, and nerves—at Cukurova University in Adana, Turkey.

He believes the siblings, who range in age from 18 to 34, are evolutionary throwbacks—a "missing link" to our forebears. (Related reading: "Was Darwin Wrong?")

Meanwhile German geneticists believe the siblings' genetic abnormality may have knocked out the gene responsible for bipedalism, or two-legged walking, in humans.

The German team, led by Stefan Mundlos of the Max Planck Institute in Leipzig, says it has located this gene on a human chromosome. (See a quick overview of human genetics.)

A 40,000-year-old skull found in a Romanian cave shows traits of both modern humans and Neanderthals and might prove the two interbred, researchers reported on Monday.

If the findings are confirmed, the skull would represent the oldest modern human remains yet found in Europe.

The study, published in the Proceedings of the National Academy of Sciences, will add to the debate over whether modern Homo sapiens simply killed off their Neanderthal cousins, or had some intimate interactions with them first.

DNA samples taken from Neanderthal bones suggest there was no mixing, or at least that any Neanderthal genetic contribution did not make it to the modern DNA pool.

But Erik Trinkaus of Washington University in St. Louis has in the past found bones that he believes show both modern human and Neanderthal traits, and now he and colleagues have found a skull.

Fact Checking 101
How Skeptic magazine was Duped
by an Environmental Activist Group

by Michael Shermer

In last week’s eSkeptic , we published highlights from a press release issued by PEER (Public Employees for Environmental Responsibility), a Washington D.C.-based environmental watchdog group. That press release, dated December 28, 2006, was headlined:

    HOW OLD IS THE GRAND CANYON? PARK SERVICE WON’T SAY
    Orders to Cater to Creationists Makes National Park Agnostic on Geology

The first sentence of the release reads:

    Washington, DC — Grand Canyon National Park is not permitted to give an official estimate of the geologic age of its principal feature, due to pressure from Bush administration appointees.

Unfortunately, in our eagerness to find additional examples of the inappropriate intrusion of religion in American public life (as if we actually needed more), we accepted this claim by PEER without calling the National Park Service (NPS) or the Grand Canyon National Park (GCNP) to check it. As a testimony to the quality of our readers, however, dozens immediately phoned both NPS and GCNP, only to discover that the claim is absolutely false. Callers were told that the Grand Canyon is millions of years old, that no one is being pressured from Bush administration appointees — or by anyone else — to withhold scientific information, and all were referred to a statement by David Barna, Chief of Public Affairs, National Park Service as to the park’s official position. “Therefore, our interpretive talks, way-side exhibits, visitor center films, etc. use the following explanation for the age of the geologic features at Grand Canyon,” the document explains.

    If asked the age of the Grand Canyon, our rangers use the following answer: ‘The principal consensus among geologists is that the Colorado River basin has developed in the past 40 million years and that the Grand Canyon itself is probably less than five to six million years old. The result of all this erosion is one of the most complete geologic columns on the planet.’

Understandably, many of our readers were outraged by both the duplicity of the claim and our failure to fact check it. One park ranger wrote us:

    You’re a day late and a dollar short on this one. As a national park ranger, I found most of PEER’s findings to be bogus. So have others: http://parkrangerx.blogspot.com

A Grand Canyon park interpreter wrote:

    This is incorrect. I have NEVER been told to present non-science based programs. In fact, I received “talking points” demanding that Grand Canyon employees present programs BASED ON SCIENCE and that we must use the scientific version supported by the National Science Foundation and the National Academy of Sciences. As an interpreter I have shared the “creation” story of the Hopi people and the Paiute people because it is culturally relative. I used these stories as a tool to introduce the scientific story. Be confident there are good people running government, too.

One of our readers directly challenged Jeff Ruch, the Executive Director of PEER:

    When I challenged that PEER guy to show me some evidence and provided him evidence to the contrary, he didn’t have much. I would say PEER did more than jump the gun. I’d say they are spreading misinformation.

Another Grand Canyon park interpreter offered this explanation:

    Ruch’s attempts to insinuate a conspiratorial link between the NPS and organized religion are misguided and founded in fervent anti-Christian opposition, not reason or the law. Ruch’s anti-Judeo-Christian bias is evidence by his lack of opposition to GCA’s selling of Native American creation myths. His misinformation campaign aims to tarnish the reputation of the NPS to leverage his position that creationism books should not be sold in the GCA bookstore. I’ve emailed a few of my contacts at GRCA, and so far, all deny any conspiracy and all freely give the canyon’s age in education programs (as does all official GRCA print material). I’ll post updates as information becomes available. Until then, don’t believe everything you read.

The reference to the creationism book being sold in the Grand Canyon bookstore — Grand Canyon: A Different View by Tom Vail — is true. It is sold in the “inspiration” section of the bookstore, alongside other books of myth and spirituality. In any case, the story is an old one now, and completely irrelevant to the claim that NPS employees are withholding information about the age of the canyon, and/or are being pressured to do so by Bush administration appointees.

Embarrassed and angered by all of this, I promptly phoned Jeff Ruch myself and inquired what evidence he has to support this claim. He initially pointed to the creationism book and the fact that the NPS has failed to address numerous challenges to the sale of same in their bookstore. When I pointed out that this is irrelevant to the claim in the press release, he then reminded me of the biblical passages that have been posted at places along the rim of the canyon. Again, I admonished, this is not evidence for his central claim. We went round and round on the phone until I finally gave up and hung up, convinced that he simply made up the claim out of whole cloth.

Not wishing to simply call Ruch a liar, and allowing myself to calm down a bit, I emailed him and asked:

    Can you tell us who in the Bush administration put pressure on park service employees? Can you name one person in the GCNP staff who says that they are not permitted to give the official estimate of the age of the canyon?

He responded:

      1. I do not know — it is at the Director’s level or above. We have been trying to find out for three years.
      2. Julie Cart, Los Angeles Times.

I contacted Julie Cart at the Los Angeles Times, who was out of town on assignment, and got her editor, Frank Clifford, on the phone. Clifford knew all about the creationism book and the biblical passages on the rim of the canyon, but said that he had heard nothing about this new claim of Bush administration appointees silencing park service staff, and that if Julie knew of such a thing the Times would be most interested in following up with the story. I then reached Julie by email, who said that she too knew of no such silence on the part of park staffers regarding the age of the canyon.

Once again outraged and enraged , I emailed Ruch to ask him why he referenced Cart, who denied his central claim. He responded:

    I referred you to Julie because of the response she got from the superintendent’s office when she covered the issue earlier — not for any new claim.

Thanks a lot. I wasted several hours tracking down that false lead. Now at my wit’s end with this guy, I point blank asked him if he made it all up. He responded:

    The interpretive staff at GCNP we are working with do not want to be identified and have gone into deep underground as the atmosphere at the park is now somewhat volatile.

Well, it would have been nice (not to mention ethical) if he would have said so in the first place. (I have now wasted about 10 hours of research time on this instead of other projects.) The referencing of sources who wish to remain anonymous is quite common in journalism and, in fact, there are laws protecting whistleblowers . The fact that no such reference was made until I pointedly accused Ruch of flatout lying makes me, well, skeptical of this explanation. His final statement to me doesn’t make me any less skeptical:

    We are issuing an amended release today that

      1. deletes reference to what interpretive staff can and cannot say and
      2. features the NPS official statement that they provide geological information to the public.

Then why did PEER issue that statement in the first place? In my opinion, this is why:

PEER is an anti-Bush, anti-religion liberal activist watchdog group in search of demons to exorcise and dragons to slay. On one level, that’s how the system works in a free society, and there are plenty of pro-Bush, pro-religion conservative activist watchdog groups who do the same thing on the other side. Maybe in a Hegelian process of thesis-antithesis-synthesis we find truth that way; at least at the level of talk radio. But journalistic standards and scholarly ethics still hold sway at all levels of discourse that matter, and to that end I believe we were duped by an activist group who at the very least exaggerated a claim and published it in order to gain notoriety for itself, or worse, simply made it up.

To that end I apologize to all of our readers for not fact checking this story before publishing it on eSkeptic and www.skeptic.com. Shame on us. But shame on you too, Mr. Ruch, and shame on PEER, for this egregious display of poor judgment and unethical behavior.
Michael Shermer
Publisher, Skeptic magazine
Executive Director, the Skeptics Society
mshermer@skeptic.com

http://www.skeptic.com/eskeptic/07-01-17.html