The American Society of Human Genetics sponsors an annual DNA Day Essay Contest. It's for grade 9-12 students from anywhere in the world.
This year's question is ...
Strolling with a skeptical biochemist
The American Society of Human Genetics sponsors an annual DNA Day Essay Contest. It's for grade 9-12 students from anywhere in the world.
This year's question is ...
Knowledgeable scientists agree that the COVID-19 pandemic began when the virus SARS-CoV-2 infected citizens of Wuhan who were visiting the wet market in the late Fall of 2019. The virus probably came from infected live animals that were on sale in the market. There is very little dispute within the (knowledgeable) scientific community, the vast majority of scientists support a natural origin.
Templeton recently awarded a grant of $607,686 (US) to study the role of transposons in the human genome. The project leader is Stefan Linquist, a philosopher from the University of Guelph (Guelph, Ontario, Canada). Stefan has published a number of papers on junk DNA and he promotes the definition of functional DNA as DNA that is subject to purifying selection [The function wars are over]. Other members of the team include Ryan Gregory and Ford Doolittle who are prominent supporters of junk DNA.
The discovery of chemiosmosis (Chemiosmotic Theory) is one the few examples of a genuine paradigm shift. It is largely due to the work of Peter Mitchell [Ode to Peter Mitchell].
I suspected that Cech is opposed to junk DNA and that suspicion is confirmed in his new book The Catalyst.
Back in 2021 Matt Ridley teamed up with Alina Chan to publish a book promoting the lab leak conspiracy theory about the origin of SARS-CoV-2. (See my summary of a review here.)
Yesterday (March 25, 2025) Michael Shermer interviewed Matt Ridley on The Michael Shermer Show podcast. The reason for the interview was to promote Ridley's new book Birds, Sex and Beauty: The Extraordinary Implications of Charles Darwin's Strangest Idea but Shermer started off the interview by asking about Ridley's previous book with Alina Chan. At 2 mins he asks,
Before we get into the new book, do you want to take a victory lap for your previous book. I mean the lab leak hypothesis is looking more and more like you called it years ago.
It's all downhill from there. I have lost all respect for Michael Shermer. It's a shame that this podcast is hosted on the Skeptic magazine website.
Ten days ago (March 16, 2025) she published an opinion piece in the New York Times where she discussed the lab leak conspiracy theory concerning the origin of the SARS-CoV-2 virus that caused the COVID-19 pandemic. As most Sandwalk readers know, there is no evidence to support that claim and plenty of evidence that the virus came from animals in the Wuhan market.
The first thing I see at the top of the results page is a summary of the topic created by Google's Generative AI, which it claims is experimental. The AI summary is different every time you start a new search but all of the responses are similar in that they criticize the idea of junk DNA. Here's an example from today,
The chapter contains an excellent summary of the history of genome sizes in bacteria and eukaryotes and a detailed description of both the c-value paradox and the mutation load arguments. The relationship between junk DNA and population size is described.
I was especially pleased to see that the author didn't pull any punches in describing the ENCODE publicity campaign and their false statements about junk DNA.
In 2012, a post-human-genome project called ENCODE, which aims to experimentally identify regions of the human genome that undergo transcription—or are bound by a set of DNA-binding proteins, or undergo chemical changes called epigenetic modifications—came to a stunning conclusion that at least 80% of the human genome is functional and that it was time to sing a requiem for the concept of junk DNA! However, this conclusion, which has been severely criticised since its publication, ignores decades of well-supported arguments from evolutionary biology arising from the c-value paradox, some of which we have described here or will do so shortly; it does not quite explain why this conclusion—if broadly applied to the genomes of other multicellular eukaryotes—would not imply that a fish needs 100 times as much functional DNA as a human; and plays “fast and loose” with the definition of the term ‘function’. While the ENCODE project, a great success in many ways, has provided an invaluable resource for the study of human molecular biology, we can safely ignore its ill-fated conclusion on what fraction of the human genome is functional.
Happy St. Patrick's Day! These are my great-grandparents Thomas Keys Foster, born in County Tyrone on September 5, 1852 and Eliza Ann Job, born in Fintona, County Tyrone on August 18, 1852. Thomas came to Canada in 1876 to join his older brother, George, on his farm near London, Ontario, Canada. Eliza came the following year and worked on the same farm. Thomas and Eliza decided to move out west where they got married in 1882 in Winnipeg, Manitoba, Canada.
The couple obtained a land grant near Salcoats, Saskatchewan, a few miles south of Yorkton, where they build a sod house and later on a wood frame house that they named "Fairview" after a hill in Ireland overlooking the house where Eliza was born. That's where my grandmother, Ella, was born.
This is a lengthy conversation between Richard Dawkins and Steven Pinker. It took place in Boston at the Chevalier Theatre in September 2024. The video appeared on YouTube last month.
In my opinion, the important point is how deeply Pinker buys into the adaptationist perspective of Dawkins. He asks no challenging questions and he seems to be of the opinion that the Dawkins' view of evolution is the dominant view of evolutionary biologists. I'm an admirer of Richard Dawkins but I have not drunk the Kool-Aid.
Pinker has drunk the Kool-Aid and most of the video is him pontificating about his incorrect views of evolution.
Much of this opposition to junk DNA stems from a massive publiciy campaign launched by ENCODE researchers and the leading science journals back in 2012.
It's likely that most of the controversy over junk DNA is related to differing views on evolution and the power of natural selection. Most people think that natural selection is very powerful so that modern species must be extremely well-adapted to their present environment. They tend to believe that complexity is simply a reflection of sophisticated fine-tuning and this must apply to the human genome. According to this view, the presence of huge amounts of DNA with an unknown function is just a temporary situation and in the next few years most of this 'dark matter' will turn out to have a function. It has to have a function otherwise natural selection would have eliminated it.
Ågren starts out by reminding us that Richard Dawkins' book The Selfish Gene was voted the most influential science book of all time in a 2017 Royal Society poll. He goes on to say,
Regardless of one's views on the poll results—or the book's argument—the far reaching sway of The Selfish Gene means that anyone interested in the history and future of evolutionary theory has no choice but to grapple with its ideas. Chief among these is the so-called gene's-eye view of evolution. This is the approach to biology originally introduced by George Williams in Adaptation and Natural Selection and elaborated and popularized by Dawkins, that it is the genes, and not organisms as Darwin originally envisaged, that deserve the status as the unit of selection in evolution. Emerging in the decades succeeding the Modern Synthesis, the gene's-eye view of evolution has become an emblem of orthodoxy in biology.
In this essay, we address the question of why we can trust science—and how we can identify which scientific claims we can trust. We begin by explaining how scientists work together, as part of a larger scientific community, to generate knowledge that is reliable. We describe how the scientific process builds a consensus, and how new evidence can change the ways that scientists—and, ultimately, the rest of us—see the world. Last, but not least, we explain how, as informed citizens, we can all become “competent outsiders” who are equipped to evaluate scientific claims and are able to separate science facts from science fiction.
Most of the essay describes an idealized version of how science works with an emphasis on collaboration and rigorous oversight. They claim that the work of scientists can usually be trusted because it is self-correcting.
Photosynthesis, which uses energy from the Sun and carbon dioxide from the atmosphere to create carbohydrates, might be the most influential set of biochemical reactions on the planet.
Here's the problem. That's not a very good definition of photosynthesis. I discuss a much better definition in a post from seven years ago: Scientists confused about photosynthesis. A better definition is that photosynthesis is the process by which light energy is captured and converted to chemical energy. The direct products of photosynthesis are ATP and reducing equivalents such as NADPH. These cofactors are used to drive all sorts of reactions in the cell including DNA synthesis, protein synthesis, lipid synthesis, and carbohydrate synthesis.
This is very obvious when you examine photosynthetic bacteria but, unfortunately, photosynthesis was initially studied in large plants where much of the chemical energy produced by photosynthesis is used to fix CO2 and make carbohydrates. This led to the widespread belief that photosynthesis is all about making carbohydrates.1. I'm using the title from the printed version of the journal. The web version has a different title. (I don't know why.)