From One Genome, Many Types of Cells. But How? - NYTimes.com

From One Genome, Many Types of Cells. But How? - NYTimes.com: "The answer, researchers are finding, is that a second layer of information is embedded in the special proteins that package the DNA of the genome. This second layer, known as the epigenome, controls access to the genes, allowing each cell type to activate its own special genes but blocking off most of the rest. A person has one genome but many epigenomes. And the epigenome is involved not just in defining what genes are accessible in each type of cell, but also in controlling when the accessible genes may be activated."

Technology Review: A Comeback for Lamarckian Evolution?

Technology Review: A Comeback for Lamarckian Evolution?: "A Comeback for Lamarckian Evolution?

"Two new studies show that the effects of a mother's early environment can be passed on to the next generation.

"The effects of an animal's environment during adolescence can be passed down to future offspring, according to two new studies. If applicable to humans, the research, done on rodents, suggests that the impact of both childhood education and early abuse could span generations. The findings provide support for a 200-year-old theory of evolution that has been largely dismissed: Lamarckian evolution, which states that acquired characteristics can be passed on to offspring.

"'The results are extremely surprising and unexpected,' says Li-Huei Tsai, a neuroscientist at MIT who was not involved in the research. Indeed, one of the studies found that a boost in the brain's ability to rewire itself and a corresponding improvement in memory could be passed on. 'This study is probably the first study to show there are transgenerational effects not only on behavior but on brain plasticity.'

"In recent years, scientists have discovered that epigenetic changes--heritable changes that do not alter the sequence of DNA itself--play a major role in development, allowing genetically identical cells to develop different characteristics; epigenetic changes also play a role in cancer and other diseases. (The definition of epigenetics is somewhat variable, with some scientists limiting the term to refer to specific molecular mechanisms that alter gene expression.) Most epigenetic studies have been limited to a cellular context or have looked at the epigenetic effects of drugs or diet in utero. These two new studies are unique in that the environmental change that triggers the effect--enrichment or early abuse--occurs before pregnancy. 'Give mothers chemicals, and it can affect offspring and the next generation,' says Larry Feig, a neuroscientist at Tufts University School of Medicine, in Boston, who oversaw part of the research. 'In this case, [the environmental change] happened way before the mice were even fertile.'"

Sounds a lot like a mechanism in support of Darwin's pangenesis theory.

Darwin, Prescient with ‘Origin,’ Is Still Influential - NYTimes.com

Darwin, Prescient with ‘Origin,’ Is Still Influential - NYTimes.com: "Biologists quickly accepted the idea of evolution, but for decades they rejected natural selection, the mechanism Darwin proposed for the evolutionary process. Until the mid-20th century they largely ignored sexual selection, a special aspect of natural selection that Darwin proposed to account for male ornaments like the peacock’s tail.

And biologists are still arguing about group-level selection, the idea that natural selection can operate at the level of groups as well as on individuals. Darwin proposed group selection — or something like it; scholars differ as to what he meant — to account for castes in ant societies and morality in people."

Essay - Darwinism Must Die So That Evolution May Live - NYTimes.com

Essay - Darwinism Must Die So That Evolution May Live - NYTimes.com: "Equating evolution with Charles Darwin ignores 150 years of discoveries, including most of what scientists understand about evolution. Such as: Gregor Mendel’s patterns of heredity (which gave Darwin’s idea of natural selection a mechanism — genetics — by which it could work); the discovery of DNA (which gave genetics a mechanism and lets us see evolutionary lineages); developmental biology (which gives DNA a mechanism); studies documenting evolution in nature (which converted the hypothetical to observable fact); evolution’s role in medicine and disease (bringing immediate relevance to the topic); and more."

Genes Offer New Clues in Old Debate on Species’ Origins - NYTimes.com

Genes Offer New Clues in Old Debate on Species’ Origins - NYTimes.com

"On Friday, Daven Presgraves, an evolutionary biologist at the University of Rochester, and colleagues published a paper in the journal Science identifying the latest such gene to be discovered. It is the second one that the team has found in fruit flies. The newly discovered gene, Nup 160, like its predecessor, Nup 96, causes reproductive isolation between the species Drosophila melanogaster and Drosophila simulans.

"Unexpectedly, the genes both produce proteins that are part of a large piece of cellular machinery known as the nuclear pore complex, a gateway that controls what molecules move into and out of the nucleus. It is still unclear why, in what Dr. Presgraves describes as a blind search for genes that cause problems in hybrids, his team twice pulled out genes involved in the nuclear pore complex or why the complex might be particularly important in the evolution of reproductive isolation.

"“The question is,” said Douglas Futuyma, an evolutionary biologist at the State University of New York at Stony Brook, “what the hell does this have to do with hybrid sterility?”"

Interesting...

High Pressure Yields Novel Single-element Boron 'Compound'

High Pressure Yields Novel Single-element Boron 'Compound': "Scientists have found the first case of an ionic crystal consisting of just one chemical element – boron. This is the densest and hardest known phase of this element. The new phase turned out to be a key to understanding the phase diagram of boron – the only element for which the phase diagram was unknown since its discovery 200 years ago."

One element in two forms creates a new crystal compound. I guess pure chemistry hasn't completely given way to applied chemistry.