Natural selection

We can’t help you. Sign noted in a computer guy’s office somewhere in North America: If after ten minutes at the poker table you do not know who the patsy is—you are the patsy. First, what exactly is Darwin’s theory anyway, other than an invite to the approved parties? Here it is: Information can be created without intelligence. That is, natural selection acting on random mutation explains the order of life we see all around us. What can’t survive won’t, and that explains how very complex life forms and structures — including the human mind — get built up. True: Things that can’t survive don’t. But why would that fact alone drive nature to produce anything as simple as a Read More ›

Devolution? From ScienceDaily: A new study offers not only a sweeping analysis of how pollination has evolved among conifers but also an illustration of how evolution — far from being a straight-ahead march of progress — sometimes allows for longstanding and advantageous functions to become irrevocably lost. Moreover, the authors show that the ongoing breakdown of the successful but ultimately fragile pollination mechanism may have led to a new diversity of traits and functions. That’s well, but it can also lead to extinction. In evolution, the research shows, selection pressure or pure chance can break a functional relationship among such loosely related traits such as the one Leslie studied, even if that relationship has been working well. In fact, once Read More ›

We are regularly told by proponents of evolutionary theory, from Darwin right up to the present day, that purely natural processes, such as random mutations and natural selection, have the ability to build, construct, fashion, purpose and create remarkable machines. Machines that rival, and in many cases surpass, our most advanced technologies. We are assured in no uncertain terms that such natural processes have this great creative power. Yet when examples are sought, we are invariably given examples that either did not come about through purely natural processes (see Berra’s Blunder), or examples that are trivial in scope. But nothing that even comes close to verifying the grand claims of the evolutionary creation story. There is a huge elephant in Read More ›

Recently, Mark Frank and I had a brief dialogue in the OP,“Didn’t everyone already know this about dogs?” I’ve decided to clean it up a bit and re-post it because after my last question, I received no responses. At the outset, I would like to say that I place no blame about lack of responses on Mark Frank or anyone else in the last OP (as my post was rather quickly buried.) Having said that, in this OP I would like somebody to address the question. After one go around where I’d suggested that “success” should be counted as an increase in genetic information, Mark Frank corrected me, writing: In biology success is breeding in the available environment. As a Read More ›

Mutations are used to explain evolution but also cause cancer. Biologists have discovered conditions for multiple mutations. Can we therefore infer that evolution via mutations is more likely? or that enhanced mutations will cause faster species degradation and extinction?

Biologists describe mechanism promoting multiple DNA mutations

DNA mutations—long known to fuel cancer as well as evolutionary changes in a living organism—had been thought to be rare events that occur randomly throughout the genome.

However, recent studies have shown that cancer development frequently involves the formation of multiple mutations that arise simultaneously and in close proximity to each other. . . .Anna Malkova, associate professor of biology in the UI College of Liberal Arts and Sciences, notes that the DNA repair pathway, known as break-induced replication (BIR), can promote clusters of DNA mutations.

“Previously, we have shown that double-strand DNA breaks, which can result from oxidation, ionizing radiation and replication errors, can be repaired by BIR,” says Malkova.

“During BIR, one broken DNA end is paired with an identical DNA sequence on another chromosome and initiates an unusual type of replication, which proceeds as a migrating bubble and is associated with the accumulation of large amounts of single-strand DNA,” she says.

In the Cell Reports study, researchers subjected yeast cells undergoing BIR to alkylating (cancer cell-killing agents) damage. “We found that the single-stranded DNA regions that accumulate during BIR are susceptible to damage that leads to the formation of mutation clusters,” explains Cynthia Sakofsky, postdoctoral fellow at the UI and one of two co-first authors on the paper. “These clusters are similar to those found in human cancer,” she says.

Importantly, say the researchers, the paper provides a mechanism to potentially explain how genetic changes form in human cancers. Thus, it will be critical for future research to determine whether BIR can form clustered mutations that lead to cancer in humans.

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