MIT News: Neurons and other brain cells snap open their DNA in numerous locations — more than previously realized, according to a new study — to provide quick access to genetic instructions for the mechanisms of memory storage. – David Orenstein, “Memory-making Involves Extensive DNA Breaking” at Mit News (July 14, 2021)
Researchers: In a discovery that challenges long-held dogma in biology, researchers show that mammalian cells can convert RNA sequences back into DNA, a feat more common in viruses than eukaryotic cells.
Challenging, they say, a central principle in biology.
Recently, our physics color commentator Rob Sheldon took issue with the use of the term “half-life” to describe the survival of DNA in fossils. He says the term has a specific meaning with respect to radioactive decay that just does not apply to other events in nature. In the biology paper at issue, with “half-life” Read More…
Tim Standish: Simpler systems do not necessarily come first because simple can be a lot harder to come up with than complex. Yes, that seems counterintuitive, but the history of technology bears that out. In some ways you could say the same about art.
Sheldon: “As a physicist, I would like to point out that biologists are misusing the word “half-life”. DNA does NOT have a half-life of 521 years. Radioisotopes have a half-life, because the nucleus is unstable to natural decay through the weak force (for isotopes of interest).” He goes on to say that the weak force of the universe “is unaffected by temperature, pressure, time, or chemicals.” Not so for DNA.
It’s a protist? “Protists are a group of loosely connected, mostly unicellular eukaryotic organisms that are not plants, animals or fungi. There is no single feature such as evolutionary history or morphology common to all these organisms and they are unofficially placed under a separate kingdom called Protista.” In short, just the sort of life form that might be doing something really different. Because nature is full of intelligence, there are probably many alternative programs out there. It all didn’t just somehow happen randomly once.
Researchers: The new shape looks entirely different to the double-stranded DNA double helix… “We think the coming and going of the i-motifs is a clue to what they do. It seems likely that they are there to help switch genes on or off, and to affect whether a gene is actively read or not.” Just a random swish of chemicals, right?
We are running out of conventional space to store information and life forms’ DNA stores it much more efficiently.
They were only discovered in 1977 and they get more unusual all the time: Microbes called archaea package their genetic material into flexible shapes that flop open in unusual ways, Howard Hughes Medical Institute (HHMI) Investigator Karolin Luger reports March 2, 2021, in the journal eLife. “Very much to our surprise, we found that these Read More…
At Smithsonian Magazine: That Mammuthus columbi originated as a new species, born of a hybridization event, “has major implications for our understanding of the population structure of Pleistocene megabeasts,” MacPhee says. The ancestors of the woolly mammoth and the Krestova mammoth had diverged from each other for about a million years before a population produced a hybrid that was different from both, giving rise to Mammuthus columbi.
If your coins keep coming up heads instead of tails, millions of years after millions of years, something is happening that isn’t mere chance.
We are told, by the by, that “Survival of the fittest’ phenomenon is only part of the evolution equation” — It seems that classical, orthodox Darwinism continues its downward trajectory in popularity.
Imagine, all that information in there doesn’t weigh anything. But it matters.
It’s not enough that DNA is a language but now it has proofreaders? Keep moving along, folks, no design to see here…