It’s autumn now, and the trees outside my window have already burst into brilliant shades of yellow and red. Soon their gorgeous leaves will fall to earth, ready to be raked, bagged, and shipped off to Pacific Region Compost.
It seems a little wasteful; these trees have put a surprising amount of energy into growing something that only lasts for six or seven months. In a 2002 study, researchers looking at 14 California blue oaks found that, by July, each of those oaks had invested about 6.6 kg of new plant material in their leaves. (This is dry mass, not including the ~85% of the leaves that were water.) One outlier had 29 kg of dry leaf mass, which in life could have weighed about a quarter-ton.
6.6 kg (or even 29 kg) might seem like chump change for a tree weighing several tons, but remember that trees need hundreds of years to get that big. Annual tree growth can be measured in the low tens of kilograms per year . . . so that extra 6.6 kg of leaf-matter represented a significant fraction of the tree’s net production, poured into something that it would soon toss aside like so much trash.
Continue reading “The Secret Lives (and Deaths) of Leaves”
Before Tuesday, nobody really knew what Pluto looked like. But since 1933, its (now former) status as “the ninth planet” merited its inclusion in countless depictions of the Solar System. Which means up until Tuesday, every time a TV show showed a picture of Pluto they were largely guessing.
So . . . how well did they guess? In the game of “pin the proper coloration and topology on the barely-visible dwarf planet”, who came closest to winning?
Continue reading “How Good Were We At Guessing What Pluto Would Look Like?”
Scrooge McDuck has a lot of money. He’s the richest duck in the world, consistently number one (or two) in rankings of all wealthy fictional characters. And the most conspicuous and iconic symbol of his wealth is his aptly-named “money bin”.
Unchanged in appearance since artist Carl Banks settled on its modern form in 1956, it’s one of those ridiculous symbols of childish excess that could never exist in real life. But . . . what if it did? How much real-life money would it take to fill Scrooge McDuck’s money bin?
(It’s more than all the gold in the world . . . but less than all the pennies.)
Continue reading “How Much Money Would It Take To Fill Scrooge’s Money Bin?”
In his 30s, Alvise “Luigi” Cornaro had become very sick. Suffering pain, fatigue, constant thirst and intestinal distress, his doctors gave him only a few months to live. He radically changed his diet, and within a year was not only still alive, but symptom free and full of energy! He maintained this new diet for decades (except for a short time in his 70s), and in 1558 (at the age of 91 . . . or 94, or 83, or maybe 74 . . . sources disagree on dates) he published a diet and lifestyle book, titled How to Live 100 Years, or Discourses on a Sober and Temperate Life.
Continue reading “How To Live 100 Years: The First Fad Diet Book”
The letter S appears nowhere in the word “dollar”, yet an S with a line through it ($) is unmistakably the dollar sign. But why an S? Why isn’t the dollar sign something like a Đ (like the former South Vietnamese đồng, or the totally-not-a-joke-currency Dogecoin)?
There’s a good story behind it, but here’s a big hint: the dollar sign isn’t a dollar sign.
It’s a peso sign.
Continue reading “Why Is The Dollar Sign A Letter S?”