Some science stuff from the New York Times

                  April 23, 2021

“We together flew at Mars, and we together now have this Wright brothers moment.” — MiMi Aung, the project manager for NASA’s Ingenuity copter on Mars, to her team celebrating the first powered flight on another world. (A second test flight on Thursday was also successful.)

“It is unusual for me to read a paper and say, ‘Wow, this is really a major advance.’ But this is a major advance.” — Valerie Horsley, a biologist at Yale, on a Stanford study showing that an existing drug can prevent scars from forming in mice.

Singularities seeking pluralities: Astronomers are debating what to call a bunch of black holes. A crush? A sieve? A riddle? See what other readers are proposing, and add your own candidate. By Alan Burdick Henry David Thoreau was 44 when, in January 1860, two years before his death from tuberculosis, he encountered Charles Darwin’s “On the Origin of Species.” The book did not change Thoreau’s life so much as complete it. For the last several years (“Walden” appeared in 1854) he had taken to meticulously documenting the flora of his native Concord, Mass. Seeds especially fascinated him: how they came to be where they were, and how variously suited they were to getting around. The flat, barbed germs of the bur marigold, he remarked in one of his hundreds of notebooks, “will often adhere to your clothes in surprising numbers” like the arrows “of some countless but invisible Lilliputian army.” His observations were a quiet but pointed rebuke to prominent biologists at the time, who held that some plants were “spontaneously generated” — from no seed at all — and that species were immutable and geographically static. In the particulars, Thoreau, like Darwin, saw something else: seeds primed for wide dispersal, a nature dynamic and continuously revitalized. “We find ourselves in a world that is already planted, but is still being planted as at first,” he wrote. Modern scientists — perhaps plant scientists above all — find themselves in similar terrain: Much is already known, but dig around a little and there’s more to discover. That’s what led researchers at the University of Michigan recently to dig up a bottle of seeds buried by another scientist 142 years ago, in what has become one of the longest-running experiments in history — the “28 Up” of carpology. The question at stake was simply stated but, it turned out, required decades to answer: How long can a seed remain dormant and still remain viable? In effect, a seed is a form of memory. Each one carries a combination of genes from its parents — not an identical copy, but true enough to sprout into an organism capable of reproducing and continuing the cycle. A seed is a vessel across time, ideally generations and ages. (In an added twist, a seed inherits the details of its dormancy — the temperature at which it should wake — from its mother plant, but the counter resets with the next generation.) So are humans, individually and collectively. A “self” is what we call an entity conscious of its own past and persistence: you are you, made up of your memories (you were you yesterday) and your expectations (you will be you tomorrow). A society is an assortment of selves that transcends the life span of any one individual and, ideally, is smart enough to build libraries and other forms of institutional memory. The enemy, of course, is forgetting. So at each scale we toss our selves into the future, hoping something of us will stick like an arrow or a burr: an heirloom, an autobiography, a bottle of seeds buried in the Michigan soil, a rover on Mars called Perseverance. Who is up ahead there, waiting to receive our selves? Us, we hope — with our library cards, our shovels, our Mars-color glasses. But we’ll have to wait and see.