What do you get when you cross a short-legged, curly-haired giraffe with albinism and a long-legged, straight haired pigmented giraffe?
A curious zoological mashup?
The question might give you science class flashbacks of those checkerboard genetics exercises known as Punnett squares. Never satisfied with simple four-square crosses between tall pea plants and short pea plants, science teachers regularly threw down the challenge of sixteen square and sixty-four square crosses of multiple traits (I plead guilty).
In a rather unique celebration of the 200th birthday of Gregor Mendel, the venerable Augustinian monk was dug up in 2022 and his DNA mapped. What would the “father of genetics” think about being hauled out of the grave 138 years after his passing?
He’d be all for it! said Daniel Fairbanks, Mendel’s biographer.
We found out that Mendel was tall, had a big brain, and was genetically predisposed to neurological diseases, a condition that plagued Mendel during his life.
Mendel never heard of genes or chromosomes, much less DNA. Still, his experiments with garden peas resulted in foundational genetic principles that still stand today.
Although his work birthed a brand-new field of biology (genetics), Mendel died in obscurity. Mendel’s methodical experiments with more than 30,000 garden pea plants and his meticulous analyses were unknown until the early twentieth century.
The most famous scientist of the nineteenth century, Charles Darwin, never heard of Mendel, despite being contemporaries – Darwin and Mendel lived, worked, and wrote at the same time. In fact, in his landmark book On the Origin of Species, Darwin wrote: “The laws governing inheritance are quite unknown.”
Why was Mendel uncelebrated in his time? Was it because he was uneducated? Quite the opposite – Mendel was university trained in botany, physics, and math. Was it because he was a monk working in isolation in an Augustinian abbey? No, Mendel’s work was published and circulated.
Why then, was Darwin celebrated while Mendel’s work languished on dusty shelves until years after his death?
In the nineteenth century, biologists were known as “naturalists”. Naturalists, like Darwin, observed, described, and sketched. Like Darwin, they filled journals with ponderings, commentaries, and hypotheses.
Mendel, on the other hand, described his work with mathematics – probabilities, ratios, and equations. He is, after all, the inspiration for those tedious Punnett square exercises.
Mendel’s work was not the kind of “biology” characteristic of his contemporaries, so he was ignored.
Mendel’s laws of inheritance were the missing piece in Darwin’s hypothesis. Darwin’s hypothesis of evolution by natural selection was seismic, but Darwin did not include a reasonable explanation for the inheritance of traits.
In the early twentieth century, we rediscovered Mendel.
Fifty years later, we confirmed that DNA was the source of all genetic variation. Just one year after that, we determined the structure of the DNA molecule, opening the door to discoveries Mendel could not have fathomed.
By 2003, we had completely mapped the human genome.
By 2012, we were using molecular “scissors” to edit the genome in living cells, a godsend to sufferers of genetic disorders like sickle cell disease.
And in 2020, we sequenced the genome of a deadly pandemic virus in record time, and in months, we had a life-saving vaccine.
Happy 200th birthday, Gregor Mendel! I think he’d be pleased with the party.
(Here’s a link to a three-minute video about Mendel, hosted by a very young Bill Nye the Science Guy: https://youtu.be/aDpLDBaEBjk)
Janet K. Ray 