Category Archives: genetics

Terrible science reporting at the Guardian: woolly mammoth “on verge of resurrection”? I doubt it, and Matthew corrects it

George Church, a well known geneticist at Harvard, is renowned for his contributions to methods of sequencing DNA as well as of “bioengineering” DNA by changing it using the CRISPR technique, which he helped develop. CRISPR gives us the ability to precisely edit DNA, inserting individual nucleotides, bits of genes, or whole genes and groups of […]

Directional asymmetry: how does it develop and how did it evolve? Part 3. Artificial selection for handedness

In the first part of this series, I discussed examples of asymmetry—both directional asymmetry (right-versus left-handedness) and  anti-symmetry (differences between sides, but in a random direction)—and raised the problem of how directional asymmetry, like the enlarged left tusk of the male narwhal or the higher left ear of the barn owl, could evolve. In other words, […]

Alfred Sturtevant: a hero of genetics

Alfred Henry Sturtevant (1891-1970), one of the first Drosophila geneticists, is also one of my personal scientific heroes. As an undergraduate at Columbia, and a member of Thomas Hunt Morgan’s famed “fly room”, Sturtevant did a remarkable piece of research, showing that genes on chromosomes are not only arrayed in a linear order, but that, by […]

Merry Xmas from Oswald Avery – but what if he had died early?

by Matthew Cobb Here’s a picture of Oswald Avery (1877-1955), at an Xmas party in his Rockefeller Institute lab, in 1940. Avery – you may not have heard of him – was the man who discovered that genes are made of DNA, in a paper published in January 1944. Avery was proposed for the Nobel […]

Another journalist falls for the modern-evolutionary-theory-is-woefully-incomplete scam: says human agriculture is an epigenetic “adaptation”

Yet another journalist seems to have fallen for the epigenetics mavens: those revisionists who think that a form of Lamarckian inheritance can be important in evolution. These people claim that the environment itself directly changes the DNA, not by altering the sequences of bases, but by somehow placing methyl groups on some of the DNA […]

Glass gem corn

Speaking of hybridization, my friend Nicole L’Or Reggia sent me some ears she grew of what’s called “glass gem corn,” which are gorgeous. I had no idea this stuff existed, though of course I’d seen less variegated “Indian corn” that appears around Halloween. Here are 12 ears: all of them are small: up to about […]

Hybrid speciation might be rare

Data show that the “normal” mode of speciation—the process in which one lineage divides into two or more species—involves the geographic isolation of populations of a single species. Over time, natural selection (and genetic drift) causes those populations to become more and more genetically different. When the genetic differentiation has gone to the extent that the separate populations […]

Natural selection in our species during the last two millennia

A question I’m always asked in popular lectures on evolution is this: “Are humans still evolving?” The answer I give is “Yes, but we have good evidence for such evolution in only a handful of traits: evolution of earlier reproductive maturity in females, later menopause, and selection for reduced blood pressure and a few other […]

A new paper confidently claims that there are four giraffe species rather than one, but I’m not so sure

The giraffe, Giraffa cameleopardalis, was first described by Linnaeus, and gets its species name from its fancied resemblance to a hybrid beast (as Wikipedia notes, the name comes from the Greek καμηλοπάρδαλις” meaning “giraffe”, from “κάμηλος” (kamēlos), “camel” + “πάρδαλις” (pardalis), “leopard”, due to its having a long neck like a camel and spots like a leopard). It’s always […]

Happy birthday, Max Delbrück!

by Matthew Cobb As Jerry pointed out earlier, the scientist Max Delbrück was born 110 years ago today. Because many readers will never have heard of him, Jerry asked me to sketch his life. Here you are: Max Delbrück (1906-1981) was a key figure in the history of post-war genetics, pioneering the molecular investigation of […]