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Trees' Leaves Grow At a Cool 70° All Over the World
biogeochick writes "Ever turn on the air conditioner on a hot day? How about a heater when it gets cold? OK, so we all know that humans act to keep themselves cool, but what about trees? A recent article on tree core isotopic evidence has shown that trees from tropical to boreal forests all grow at 70 degrees. The study, published in Nature by some fantastic researchers (so one of them is my adviser, so sue me) and covered by NPR on All Things Considered, has shed some light on the convergent temperature at which trees perform photosynthesis." Update: 06/19 21:31 GMT by T : I give, I give -- that's 70 degrees Fahrenheit.
That's insane, that's so hot we'd burn our fingers if we touched the trees?!
That's 21C for anyone living in the 21st century.
Spelling mistakes, grammatical errors, and stupid comments are intentional.
That's about 21.11 degrees Celsius.
Americans really need to start using the metric system. Honestly, it really is worth the effort to switch.
May the Maths Be with you!
The first link is to a subscription-only site.
The second contains "warm" and fuzzy quotes like the following:
"Trees in chilly climates also have ways to make their leaves or needles retain more heat from the sun. Pine needles, for example, clump together. Think of gloves and mittens, Helliker says. If you're wearing gloves, wind can easily whip heat away from your individual fingers, leaving you cold. But if your fingers are all together in a mitten, they're going to be warmer.
Richter says the discovery isn't just fascinating science. It gives her a special kinship with trees.
On a recent day in Philadelphia when the mercury was near 100 degrees, she said, "I was staring at a hickory tree and its leaves were down â" they had wilted," she says. "And I was thinking, hey, it's hot, I'm hot. They enjoy 70 degrees, and I enjoy 70 degrees, too.""
A special kinship with trees?!? How did this make it to Nature?
The green is reflected. Red and blue are absorbed. Why plants are green
... when placed into moist locations. Give me five!
Ok, no good comes from watching Scrubs.
with hanging toilet paper! It's over the top, Like it or not! Allways and everywhere unless your some kind of freaking psychopath!
How much is your data worth? Back it up now.
I've often wondered why it is that humans prefer air temperatures somewhere around 72Â. It'd seem more reasonable for us to prefer something closer to 98Â. I suppose the temperature differential between the 2 is what's required to keep us at a steady state, dissipating the energy we burn.
I find it even more remarkable that trees prefer nearly the same temperature that humans do.
Software sucks. Open Source sucks less.
Don't use that M-word around trees. They'll get very nervous hearing that!
Saskboy's blog is good. 9 out of 10 dentists agree.
Jesus F Christ, forget the kinship. The quote about pine needles is just about the most retarded thing I've heard in ages.
Having lots of thin needles near each other is actually a pretty good heatsink design. No, seriously. Not as good as some ducted designs, and not as cheap to make as shaved copper fins, but nevertheless, if you're going to blow air through it, it gets heat out rather impressively well. Per weight, it has a _lot_ of surface to exchange heat through.
Evergreens don't "stay warm like fingers in a mitten" in winter, but, among other things, have one or more of the following reasons for what they are:
1. The needles allow the snow to fall off the trees easier than a broad leaf. (But not all evergreens have needles, btw.)
2. Many contain chemicals that act, effectively, like anti-freeze. You can't stay warm like fingers in a mitten when you can't produce your own warmth. Your fingers stay warm in a mitten just because they produce their own heat, and the mitten keeps it in. If you were cold blooded, like a tree, even keeping them tight together and even a mitten wouldn't last you all winter. The best you can do is try not to freeze as early.
But even so, they're photosynthesizing a lot slower in winter, and when the temperature drops enough and that water freezes anyway, not at all.
3. They grow in areas with less sunlight, warmth and soil nutrients, so they can't afford to just lose the leaves and consume nutrients to make more in spring. So even if temperature drops enough that they do freeze, they keep their leaves because they can't afford to just drop them all and make a new batch later. They keep their needles for _years_.
4. The thick needles and waxy cover help conserve water. Basically they try to lose as little as possible, among other things, because #2 and because getting more from the ground is a pain in winter anyway.
So, seriously, this looks to me like the most retarded kind of pseudo-science. The kind that just imagines some fairy-tale explanation. Worse yet, one based on little more than anthropomorphizing the damn trees.
A polar bear is a cartesian bear after a coordinate transform.
Mod parent down. This is absolute rubbish, how did it get to +5 informative? I assume it's there as a joke so it should only be +5 funny, or possibly now, +5 fooled Slashdot. I am a plant physiologist, there are three basic types of chlorophyll in land plants, a,b & c. They have slightly different spectra, but they are not blue and yellow, they all have minimal absorbance in the green part of the spectrum and thus look green. The yellows and reds in senescing leaves are from carotenoids and anthocyanins.
Si hoc legere scis nimium eruditionis habes.
The evolution of chlorophyll followed (perhaps in Cyanobacteria) in organisms at the bottom of the sea. These were the first organisms to fix carbon dioxide. Being at the bottom of the ocean, only the far bands of visible light were available to them (blue and red), and hence green chlorophyll evolved.
Since then, accessory pigments have also evolved (e.g. phycobiliproteins), which have reclaimed other parts of the visible spectrum, and changed the colour of the plants or algae.