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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.
Since I can't read the article, I'll speculate wildly. I've often wondered why chlorophyll isn't black for maximum sunlight absorption. The impression I get from the paragraph of the article that I can read without paying for it is that leaves maintain the optimum temperature for photosynthesis. Is green perhaps the easiest color to manufacture that will keep the leaves at the right temperature, even in full sunlight? That would explain why green was selected over other colors despite the fact that it's reflecting away a huge percentage of the sun's light.
End of lesson. You may press the button.
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!
there. we have another outdated, ancient unit of measure in this thread now. heads of oxen.
Read radical news here
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
Should be 79.43 degrees Smurdley
If you losers would get on the Potrzebie system we could avoid all this confusion.
run your house cooling lines right into the trunk baby....
70 degrees sounds kinda sweet-- better than running the rods 150 feet underground...
every day http://en.wikipedia.org/wiki/Special:Random
... 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.
I feel sorry for the article poster. :/ Don't worry, when I read it the first time through, I thought it was 70 degrees F. I guess that's just my outdated mindset. I have a hard time calculating differences between metric and english units that I have a bookmarked site to help me convert. :S
Anyway, interesting story. Trees, obviously, would always need some way to cool down or to keep warm throughout the seasons.
-Aegis Runestone-
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.
Actually, he's saying it's 70 degrees dougmc, which coincidentally lines up with the Kelvin scale, but which uses degrees.
Are you saying you don't get an F for what they think?
... C.
I
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
And yet, the plants flourish. Notably, kudzu flourishes and grows so fast that you can almost see it happen -- which means it's not waiting for cooler weather.
Something isn't adding up for me here.
Lacking <sarcasm> tags,
...tree hugging environmentalist freak. How the hell this dribble ever made it to Slashdot is beyond me.
As if a tree is aware of the temperature it maintains anyway... A tree is an organism, albeit a very efficient organism. The thousands of years of growth and development have dictated the system by which it generates and stores energy, not some longing for comfort. Give me a break. Next thing you know, environmentalists will be trying to develop a method of using photosynthesis to generate electricity.
When will it end?
Take your mod and shove it!
TFA should be: "TTrees' Leaves Grow At a Cool 70 in the USA and Myanmar And At a Cool 21 Everywhere Else Where The Middle Ages Have Ended And The Age Of Enlightment Has Arrived", but they ran out of space. Strings in Slashdot have a 120 character limit, you know.
It was smart to post as an AC. 70K (without the degrees) is damned cold! 70 degrees C is really hot.
I do wish we'd switch to metric here but I doubt we will in my lifetime. And for the record, I'm Canadian, living in the US. I STILL haven't gotten a feel for American units, but I'm getting a little better at doing the conversions in my head. That being said, I had no idea what 70F was until googling it. Apparently you haven't lived here long since temperatures are pretty much always given in Fahrenheit here. In fact (sadly) most US citizens couldn't tell a metric temperature other than 0C or 100C if their life depended on it.
In this case it isn't so much the summary that is misleading as the original article. If you read the actual paper (assuming you have a Nature subscription), which doesn't appear to be linked from Nature's own news article, you will find that they aren't quite saying that leaf temp is maintained at 21C. Firstly, the 18O data actually mean that the sugars used to construct the cellulose measured were built at 21C, not that photosynthesis occurs at 21C. Secondly, this is an AVERAGE temperature over the lifetime of the tree! Thirdly, it relies on a model, which I'm not about to go through here. But I did work in the lab with people that have spent a lot of time working on this area (they are cited multiple times by the authors here) and I suspect that the conclusion as presented is probably a vast simplification.
Si hoc legere scis nimium eruditionis habes.
I live on an island in the north Irish Sea, but despite this, I have Medeterranean dwarf fan palms growing pretty vigorously in my garden (the Gulf Stream keeps us from getting much in the way of freezing weather in the winter). I've also got a couple of Canary Island Date Palms (rather slow growers here) and a couple of washingtonia (native of southern California/Mexico).
Oolite: Elite-like game. For Mac, Linux and Windows
I grow pot professionally. I know these things. And so does the parent poster.
Dear God, Slashdotters! Everyone knows it's twice half as much.
A combination of heat trapped by clothing and heat generated by movement (including that of blood, etc.)
We have too much control over air temperature, and have trained our thermoreceptors to be oversensitive to temperature. Those who spend their childhood outdoors (e.g., indigenous peoples) are not as sensitive to temperature variability as us refrigerated beings.
----
"Those who quote others are more likely to one day be quoted" -Tom Planter
As for "other cooling methods," the tree trunks are also warm (thus not conduction), no cool air for convection, and night-time radiation (even if it were worth much in the soup called "air" in the Delta) isn't much help to cool at the same time as photosynthesis.
Lacking <sarcasm> tags,
1. Roll out a few pieces
2. Press roll with your arm
3. Yank the pieces off with a twist of your wrist
No need to put down your book just to wipe your ass. More seconds with sweet scifi!
Hmmm, I think I need to change my password.
The Kruger Dunning explains most post on
Um, 'cause it's Base-10 and way easier to teach to future generations?
Base-10 sucks, too few prime divisors.
The Egyptians figured out children could learn to count in base 12 on their finger knuckles just fine. That way we won't have to start navigating in radians to get to your base-10 nirvana.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
One of most interesting biological articles in a long time and the first 20 posts that are modded up are about a mistake/slip up on the temperature.
⦠and for the record there are virtually no trees at 70 dregrees, north or south, doing much of anything whatsoever!
It's just the transition time is taking a bit longer than expected.
Engineering is the art of compromise.
does this also apply to Penis enlargement?
(it's for a friend actually)
"degree Rankine", same as "degree Celcius," "degree centigrade," and "degree Fahrenheit." Kelvin is the odd man out.
"National Security is the chief cause of national insecurity." - Celine's First Law
Since it was pulled out of someone's ass:But seriously, when did Fahrenheit stop working?
http://www.straightdope.com/classics/a4_188.html
At least with Celsius it relates to the states of a natural occurring substance.
I just read TFA. It was published in Nature. A British science journal. And it says :
u think human is the best?
human is best to learn and nothing built-in
hahahahaha
I never thought I would say this combination of words: Thank you, Geekoid and Aegis! xo, Biogeo.
I suffer for my humor...
Mine was a play on 'F'ahrenheit and 'C'elcious.
Ah well...
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
Comment removed based on user account deletion
Yet another temperature scale: 70 degrees Delisle = 128 degrees Fahrenheit. They like it hot hot hot!
That's 21C for anyone living in the 21st century.
In the US that's the middle of the 20th century. The "powers that be" tried to switch us to C and km around the '70s or so. But we just ignored 'em and eventually they gave up.
(Might have been different if they hadn't picked about the same time to switch it "Celsius" from "Centigrade". But probably not. B-) )
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
... 10.476 feet per gallon
GP must drive a Hummer... perhaps only in reverse, like Mother Goose.
Reminds me of a cartoon in a hot rod magazine several decades ago.
Hot rod at the gas pump with a couple guys in it while it idles. The third guy, at the pump, is yelling "Shut it down! It's gaining on me!".
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
tsk tsk Mr. Conifer. You don't have leaves.
They're using their grammar skills there.
I for one, welcome our new 70 degree rotated, 70 degrees temperature, 70 degrees educated, located somewhere between 70 degrees east and 6 degrees from kevin bacon *, tree overlords.
* theres bound to be a tree somewhere in that movie...
We sense the surrounding temperature through tiny sensors in the skin which are extremely sensitive to temperature. When these sensors register about 20 degrees and our whole body is at a good temperature, we feel comfortable. Higher than that means we're getting too hot.
The sensors send signals to the the brain, from both internal and skin sensors. The hypothalamus (a primitive part of our brain) controls the action, like a furnace controller/thermostat. The hypothalamus integrates the signals to learn how warm the internal body is and how the body surface is changing: warming or cooling. Then it decides what to do: OK means do nothing; otherwise it begins start regulation of body temperature to get it right again.
When the hypothalamus decides to cool the body, we sweat (to cool the skin through evaporation) and our skin blood vessels widen (to bring warm blood to the skin where it can cool).
If we were feeling the warmth only when the ambient temperature reaches the same value as the deep body temperature, it would be too late and hyperthermia would develop. The body temperature would soar and eventually cause brain damage.
The sun is basically yellow. Green means that it's pretty absorptive at yellow and lower spectra and rejects green and higher. Including UV.
Alternatively, the plant's don't get to tune what chemical they use, they use whatever is available that works. And it may not be able to GET to black because it has no way of getting from the blue cyanobacteria had to the black they could do with now. Green may be the best they can manage.
freedom?
Latitude?
Longitude?
Kelvin?
Farhenite?
Celcius?
seperation?
from a randomly chosen spot on Uranus?
from the trunk?
towards the trunk?
GIGO FTW
--- Users are like bacteria -> Each one causing a thousand tiny crises until the host finally gives up and dies.
the 1 Kelvin just happens to about 1 degree C but the definitions are indpendent
n/t
Look at the facts.
Trees do not hurt the planet, engage in war, or show hatred.
Trees live side-by-side and form communities that used to cover entire continents.
We use the skeletons of trees for our houses, decks, guitars, furniture, and we burn their bodies for heat.
Trees have orgasms that last for months. At least the darn pine trees by my house. I mean there is pollen all over everything --- eeewwww. Then again, there ARE stiff all year long.
Trees do differential calculus while we all sleep. They have been stargazing for nearly one billion years. They are pretty good at high energy physics too.
So hug a tree, but don't get any on you.
- I live the greatest adventure anyone could possibly desire. - Tosk the Hunted
Even if one accepts that a US American website (even with a known-international user base) always uses degrees Fahrenheit for temperatures, "degrees" is quite inaccurate as it's a heavily overloaded unit. I actually mistook the figure in the headline for an angle (reading the "cool" as something only understandable after reading TFA) until I read the clarification at the end. When using degrees for temperature, always specify which kind of degrees so people don't have to guess what they're dealing with. There's too many kinds of degrees that commonly occur as two-digit numbers.
Also, when giving temperatures always offer conversions into all formats readers can be expected to need. Slashdot is a US American site, so Fahrenheit is neccessary. Many users come from countries that aren't the USA or Belize so Celsius is neccessary as well. Kelvin is only useful when talking about very low temperatures and all other systems fill narrow niches at best, but C and F should always be given.
Doesn't matter where your server is located; a website should always try to accomodate for its user base.
USE HOT GRITS WITH STATUE OF NATALIE PORTMAN (NAKED AND PETRIFIED)
Next time don't use "sex" or "money"
www.purevolume.com/martyd
I just entered "40 miles per gallon = ? rods per hogshead" into Google.
The result returned:
40 miles per gallon = 806 400 rods per hogshead
I [heart] the Simpsons-watching Google Calculator engineers.
Have you filed the patent disclosure yet? Sounds like a genetic engineering potential. I'll give you the sales pitch.... "Sap away the heat!" Sometimes the silliest ideas are marketable. Ops... looks like someone is selling a mechanical version of it now. http://www.mkicorp.com/a-t-transpiration.asp
Call it ...
Toilet Humor
How much is your data worth? Back it up now.
to see so many otherwise individualistic geeks yelling "conform" at the top of their lungs!
By the logic employed by many here, surely even more than adopting a common temperature scale, the world would benefit from people throwing away their native tongues and all adopting English as a first language instead. I don't see anyone arguing for that though.
Maybe people should talk about the article instead of having this silly conversation. Or if truely necessary, someone should submit this discussion to Slashdot as "Geeks Debate Temperature Scales."
We Americans have no problem figuring out the temp...our system works perfectly fine.
ALL these systems are arbitrary, some a little more, some a little less.
All these systems work just fine for the people using them. (sort of like language?)
The question is obvious: what is the ROI for switching? Usually pretty shitty. Very few make the switch, until such time that it is profitable and expedient to do so.
Until then, STFU silly nerds!
One comment also says that people have actually measured leaf temperatures directly (using thermometers, of all things): leaves can get very hot, and very cold, and that they don't usually keep a constant avg temp.
Another comment states that out that you're using ratios of oxygen isotopes to infer the average temperature. This ratio is constant in the atmosphere, and perhaps all you're describing is the atmospheric ratio, reflected in the cellulose samples you tested. So maybe all we can infer is that the world's average temperature doesn't vary very much, but then again that's kind of a tautology, isn't it?
Timothy, would be willing to provide a URL on your dept's website for us mere mortals to read the full article? I'm sure Nature won't mind, and we might get a better sense of whether what you say is true.
Ahhhh... The good old "Think of the children" defense.
I wondered how long it would take to get trotted out.
To counter the "fit to breed" snipe: How fit is someone that won't train their children?
Lest it get ugly lets finish up with a family anecdote:
One of my sisters was hollering at my mom to help her one day, and my mom told her to come here.
She did.
Only problem was she neglected to tear off the toilet paper she was bringing my mom.
They ARE out to get you simply because They are in it for themselves and they don't care about you.
If you just narrowed temperature down to a human comfortable scale, Fahrenheit does the job of describing it quite well with only two digits. Celsius on the other hand requires going to the right of the decimal point to adequately describe a noticeable change, so then you need 3 or 4 digits to do the exact same job. It's really a matter of convenience. Also if you consider 0 F too dang cold, and 100 F too dang hot, it also comes that approximately 3/4 of that range is actually pretty comfy in human terms. It's actually a better measurement in regards to an human occupied environment, since the range of 0 to 100 has more useful resolution. That might explain why the U.S. still uses it.
Now if you want something that allows for scientific calibration based on the boiling and freezing points of water at sea level, then sure Celsius is plenty good for that.