A theory in crisis!

A theory in crisis.

A team of Canadian and French scientists has shed new light on what’s being called the Earth’s “last universal common ancestor,” the 3.8-billion-year-old microscopic organism from which all living things – bacteria and humans and sunflowers alike – evolved.

The researchers, including Universite de Montreal evolutionary geneticist Nicolas Lartillot and colleagues from the Universite de Lyon, say they’ve discovered that “LUCA” was not the heat-craving entity scientists have traditionally believed it to be. Instead, the team argues in the journal Nature, the primitive speck of life that became mother and father to all plants and animals preferred relatively cool temperatures of less than 50 C – not the 90 C habitat generally assumed to be its ideal simmering temperature in life’s primordial soup.

“It is generally believed that LUCA was a heat-loving or ‘hyperthermophilic’ organism – a bit like one of those weird organisms living in the hot vents along the continental ridges deep in the oceans today,” said Nicolas Lartillot, a bio-informatics professor at the U de M. “However, our data suggests that LUCA was actually sensitive to warmer temperatures and lived in a climate below 50 degrees.”

The study states that the initial offspring lineages of the common ancestral life form must have adapted later to higher temperatures, “possibly in response to a climate change of the early Earth.”

The study provides a new look at the planet’s biological beginnings – even before the rudimentary chemical ingredients of life had assembled into DNA strands that would become fundamental to evolution.

“The group’s findings are an important step toward reconciling conflicting ideas about LUCA,” a research summary states. “In particular, they are much more compatible with the theory of an early RNA world, where early life on Earth was composed of ribonucleic acid (RNA), rather than deoxyribonucleic acid (DNA).”

The researchers note that heat-sensitive RNA was “unlikely to be stable in the hot temperatures of the early Earth” but that LUCA must have found “a cooler micro-climate” in which to develop.

“It is only in a subsequent step that LUCA’s descendants discovered the more thermostable DNA molecule, which they independently acquired (presumably from viruses), and used to replace the old and fragile RNA vehicle,” Lartillot said in the statement. “This invention allowed them to move away from the small, cool micro-climate, evolve and diversify into a variety of sophisticated organisms that could tolerate heat.”

Oh, hang on. It looks like scientists are just debating how evolution occurred, not whether it occurred. Business as usual.

More Michael Heath mumbo

He’s full of mumbo. Jumbo, too.

A lot of teenagers are unable to speak with their parents about sex. Either it’s awkward or they’re made to feel bad about their desires because of the irrationality of religion or some other shallow thought. But, of course, Michael Heath of the Maine Family Policy Council embraces shallow thought. He favors changing the current law in Maine concerning parental consent for birth control and other sexual reproductive health issues.

Maine law has allowed minors contraception without parental consent for more than 30 years, but the issue was brought back to the forefront last fall when the Portland School Committee voted to allow contraceptives to be given to girls at the school as part of the services offered at a city-run health center in the school.

Mike Heath, executive director of the Maine Family Policy Council which supported Smith’s attempts to limit the confidentiality law last session, believes Family Planning is working to hard to protect the current law because it fails to align with public sentiment.

“The public knows the Maine Family Planning Association is wrong,” Heath said this week. “The MFPA is holding the public forums because they are selling something the public has no interest in buying. The public knows that good laws honor the nobility of sex inside of marriage and the danger of fornication.”

(The MFPA is sponsoring public forums on the issue.)

Oh, Mikey. The state has no business “honoring” sexual practices within the purely legal, purely secular contract of marriage. As such, it does not do this. What’s more interesting here, however, is how childish Heath’s views on sex really are. By denying minors the right to their reproductive health, “the danger of fornification” is actually increased. What’s more, Maine law allows for a person as young as 14 to consent to sex as long as the other person is within 5 years of age. At the age of 16, a person may consent to sex with a person of any age, from 14 to 140, it’s legal. So if Heath is right (his track record says he isn’t) and minors need to get parental consent for their reproductive health issues, then that undermines Maine law. That is, Maine law states a person is responsible enough, in the eyes of the state, to engage in sexual activity at that aforementioned age levels. Forcing consent would imply that, no, these people are not responsible enough. Essentially, the freedom to engage in sex within the prescribed laws would disappear because the sexual activity of a 17 year old would become the responsibility of his or her parents.