THE HAPPIEST DAY OF BATMAN’S LIFE. One of the one-hour drawings I’ve been doing, available for purchasing by you right here. All the ones thus far are here. Subject suggestion: “The happiest day of Batman’s life.” I’ve reopened one hour drawings now that I don’t have to get them done before Christmas (it’s too late to ship in time). So if you’re not in a hurry, feel free to spend yourself silly.
Yesterday our resident photography whiz, Alan Taylor, decided to try an experiment: he solicited reader requests for news photos. The response was great, the subject matter varied, and he says the task of finding the images and composing the entry was great fun — images ranged from massive solar flares to tiny insects, taken in places from Thailand to outer space, and much more. Read more.
[Image: Alik Keplicz/AP]
I spent a fair bit of extra time on it, because it was for a friend. Weird fact: though I’ve been a lifelong science guy (or as much of a science guy a high school dropout cartoonist really can be) I’d never seen Cosmos until this. I watched the first episode, and it was 1000% crazier than I expected (in a good/weird way).
UPDATE! I’ve turned this image into color and black and white prints, available here. If you’re into that!
The Pentagon is blocking LGBT and progressive websites, but not their conservative counterparts. Does your favorite blog make the censorship list?
Marijuana has not been de facto legalized, and the war on drugs is not just about cocaine and heroin. In fact, today, when we don’t have enough jail cells for murderers, rapists, and other violent criminals, there may be more people in federal and state prisons for marijuana offenses than at any other time in U.S. history
Eric Schlosser on the U.S. war on marijuana in the August 1994 issue of The Atlantic. His cover story eventually became Reefer Madness: Sex, Drugs, and Cheap Labor in the American Black Market.
Read more at The Atlantic
And so my dream of seeing a redwood as tall as the Burj Khalifa comes to a disappointing end. Still, the science behind the limitation is a pleasantly interesting consolation prize. —MN
Why trees can’t grow taller than 100 metres
TYPICALLY, the taller the tree, the smaller its leaves. The mathematical explanation for this phenomenon, it turns out, also sets a limit on how tall trees can grow.
Kaare Jensen of Harvard University and Maciej Zwieniecki of the University of California, Davis, compared 1925 tree species, with leaves ranging from a few millimetres to over 1 metre long, and found that leaf size varied most in relatively short trees.
Jensen thinks the explanation lies in the plant’s circulatory system. Sugars produced in leaves diffuse through a network of tube-shaped cells called the phloem. Sugars accelerate as they move, so the bigger the leaves the faster they reach the rest of the plant. But the phloem in stems, branches and the trunk acts as a bottleneck. There comes a point when it becomes a waste of energy for leaves to grow any bigger. Tall trees hit this limit when their leaves are still small, because sugars have to move through so much trunk to get to the roots, creating a bigger bottleneck.
Jensen’s equations describing the relationship show that as trees get taller, unusually large or small leaves both cease to be viable (Physical Review Letters, doi.org/j6n). The range of leaf sizes narrows and at around 100 m tall, the upper limit matches the lower limit. Above that, it seems, trees can’t build a viable leaf. Which could explain why California’s tallest redwoods max out at 115.6 m.