Beta

×

Welcome to the Slashdot Beta site -- learn more here. Use the link in the footer or click here to return to the Classic version of Slashdot.

Thank you!

Before you choose to head back to the Classic look of the site, we'd appreciate it if you share your thoughts on the Beta; your feedback is what drives our ongoing development.

Beta is different and we value you taking the time to try it out. Please take a look at the changes we've made in Beta and  learn more about it. Thanks for reading, and for making the site better!

Trees' Leaves Grow At a Cool 70° All Over the World

timothy posted more than 6 years ago | from the 73°-is-right-out dept.

Earth 537

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.

cancel ×

537 comments

Sorry! There are no comments related to the filter you selected.

Get a real unit. (5, Funny)

Anonymous Coward | more than 6 years ago | (#23864401)

That's insane, that's so hot we'd burn our fingers if we touched the trees?!

Re:Get a real unit. (4, Funny)

dougmc (70836) | more than 6 years ago | (#23864505)

No, 70 degrees is too cold!

Hell, there have been some superconductors found that work at 70 degrees!
Perhaps rather than `get a real unit', just give a unit, real or not.

Re:Get a real unit. (4, Funny)

ConceptJunkie (24823) | more than 6 years ago | (#23864681)

No, 70 degrees is about four-fifths of a right angle.

I just hope someone doesn't come around and rotate my trees, because they might die!

Re:Get a real unit. (5, Funny)

dougmc (70836) | more than 6 years ago | (#23864777)

touche!

And in a similar vein, I thought I was only six degrees away from Kevin Bacon? Or was that Paris Hilton? Either way, *70* degrees seems very excessive!

It took me 10 years of school to get two degrees ... 70 would take ... a long time.

Diploma mills (1)

tepples (727027) | more than 6 years ago | (#23865249)

It took me 10 years of school to get two degrees ... 70 would take ... a long time.
Not if you go to the right non-accredited school [wikipedia.org] .

Re:Diploma mills (5, Funny)

saskboy (600063) | more than 6 years ago | (#23865587)

Don't use that M-word around trees. They'll get very nervous hearing that!

Re:Get a real unit. (1)

GeekDork (194851) | more than 6 years ago | (#23864863)

You know, it'll always be 70 degrees relative to something... But wouldn't that be radians today?

Re:Get a real unit. (1)

sjbe (173966) | more than 6 years ago | (#23866055)

No no no... it's just off of East-NorthEast

Re:Get a real unit. (4, Insightful)

Microsift (223381) | more than 6 years ago | (#23864811)

If I recall my chemistry correctly, I think you mean 70 Kelvin, the Kelvin scale does not use degrees.

Re:Get a real unit. (1)

msauve (701917) | more than 6 years ago | (#23865441)

No, Rankine [wikipedia.org] .

Re:Get a real unit. (1)

Maxo-Texas (864189) | more than 6 years ago | (#23865713)

Actually, he meant 70 Kevin.

Trees, not being human are actually 70 degrees of seperation from Keven Bacon.

This is why we specify units... (0)

Anonymous Coward | more than 6 years ago | (#23865771)

Actually, he's saying it's 70 degrees dougmc, which coincidentally lines up with the Kelvin scale, but which uses degrees.

Re:Get a real unit. (1)

Kell Bengal (711123) | more than 6 years ago | (#23865151)

I insist we measure temperature on an absolute scale - Rankines specifically.

Re:Get a real unit. (2, Funny)

maxume (22995) | more than 6 years ago | (#23865793)

Are you going to insist me in the face if I keep using Fahrenheit?

Shameless karma whore (5, Informative)

LighterShadeOfBlack (1011407) | more than 6 years ago | (#23864409)

That's 21C for anyone living in the 21st century.

Re:Shameless karma whore (5, Funny)

Actually, I do RTFA (1058596) | more than 6 years ago | (#23864437)

That's 21C for anyone living in the 21st century.

That's 294.15K for anyone who has (somewhat at least) overcome an infantile obsession with water.

Re:Shameless karma whore (4, Funny)

Atzanteol (99067) | more than 6 years ago | (#23864539)

And 529.67 rankine for those of us who are simply better looking.

But seriously, when did Fahrenheit stop working?

Re:Shameless karma whore (1, Insightful)

gbjbaanb (229885) | more than 6 years ago | (#23864703)

But seriously, when did Fahrenheit stop working?
on a technology blog you should know better than to question the need for continual changes in favour of the latest system.

Re:Shameless karma whore (5, Funny)

johannesg (664142) | more than 6 years ago | (#23864707)

But seriously, when did Fahrenheit stop working?
He passed away in 1736. It is likely that he stopped working some time before that point, although we cannot be sure that he didn't die at his desk.

Re:Shameless karma whore (5, Insightful)

Simon Brooke (45012) | more than 6 years ago | (#23865147)

And 529.67 rankine for those of us who are simply better looking.

But seriously, when did Fahrenheit stop working?

About the same time that furlongs per fortnight ceased to be a useful measure of speed.

Re:Shameless karma whore (5, Funny)

Xaroth (67516) | more than 6 years ago | (#23865479)

My car gets 40 rods to the hogshead, and that's the way I likes it!

Re:Shameless karma whore (4, Informative)

flyingfsck (986395) | more than 6 years ago | (#23866091)

You know, even a ship does better than that I think, that is about 10 feet per gallon.

Re:Shameless karma whore (1)

Atzanteol (99067) | more than 6 years ago | (#23865659)

The third largest nation in the world (by population) still uses Fahrenheit. I wouldn't consider that quite in the same league.

Re:Shameless karma whore (4, Insightful)

Simon Brooke (45012) | more than 6 years ago | (#23865983)

The third largest nation in the world (by population) still uses Fahrenheit. I wouldn't consider that quite in the same league.

Which is another way of saying 'less than 5% of the population of the world still uses Fahrenheit'. Looked at that way I'd assert it's in exactly the same league, or, indeed, the same 5.560 kilometres.

Re:Shameless karma whore (3, Funny)

Myrddin Wyllt (1188671) | more than 6 years ago | (#23865995)

In the immortal words of the sea-captain in Blackadder:

"Opinion is divided on the subject - I say it is; everyone else says it isn't."

(OK, not everyone, Burma and Libya are still holding out as well)

Re:Shameless karma whore (1)

Myrddin Wyllt (1188671) | more than 6 years ago | (#23866095)

err.... Liberia, not Libya, apparently.(Just looked it up - that'll teach me not to believe everything sea-captains in pubs tell me).

So an extra 3 million people rather than 6 million....

Re:Shameless karma whore (5, Funny)

RoverDaddy (869116) | more than 6 years ago | (#23864567)

Considering how much of my body happens to be water, I don't consider it an infantile obsession. Some people have an infantile obsession with making water, but that's something different.

Re:Shameless karma whore (4, Funny)

Bandman (86149) | more than 6 years ago | (#23864697)

And in somewhat less than 10 comments, this has become a pee thread.

Nice job. /sigh

You did it (-1)

Anonymous Coward | more than 6 years ago | (#23864855)

He was talking about spit. YOU are the one that made this into a pee thread.

Nice job. /sigh

Re:Shameless karma whore (1)

maxume (22995) | more than 6 years ago | (#23865881)

I tooted!

Re:Shameless karma whore (1)

Rogerborg (306625) | more than 6 years ago | (#23866111)

Fewer, not less. And we're back to pedantry again.

Re:Shameless karma whore (4, Funny)

Al Al Cool J (234559) | more than 6 years ago | (#23865481)

And it's 1.22 radians, for anyone who thought "a cool 70 degrees" meant a rakish angle.

Re:Shameless karma whore (1)

infolib (618234) | more than 6 years ago | (#23865837)

I always think of room temperature as 25 meV...

Re:Shameless karma whore (1)

Moridineas (213502) | more than 6 years ago | (#23864449)

Gotta love the units nazis. I'd really think there would be better things to get upset about than what temperature unit someone else chooses to use!

Re:Shameless karma whore (1)

colesw (951825) | more than 6 years ago | (#23864475)

Who wants to read the article, but at least in the summary they could have indicated what unit they were using.

Re:Shameless karma whore (-1, Offtopic)

Anonymous Coward | more than 6 years ago | (#23864803)

Who wants to read the article, but at least in the summary they could have indicated what unit they were using.
Which. At least in the summary they could have indicated which unit they were using. ;)

Re:Shameless karma whore (5, Insightful)

LighterShadeOfBlack (1011407) | more than 6 years ago | (#23864895)

It's got nothing to do with getting upset. It's about sheer convenience. In large swathes of the World the metric system has been the only system taught for decades and this is an internationally read website which has (I suspect) a demographic bias towards younger people. Providing temperatures in a system that large portions of its readers may not know off the top of their head seems silly and unncessary when all that was needed was a "70F (21C)" to save potentially some x thousand readers have to go Google it or, God forbid, read the article.

Re:Shameless karma whore (1)

Moridineas (213502) | more than 6 years ago | (#23865269)

Ahh I see, so when you said "for anyone living in the 21st century" that wasn't meant to be derogatory at all, you were just referring to ... the young people? right on

Re:Shameless karma whore (1)

umghhh (965931) | more than 6 years ago | (#23866105)

ughh are we supposed to read some article? What article?

Re:Shameless karma whore (0)

Anonymous Coward | more than 6 years ago | (#23865007)

Because that person is using a unit that's only used in 3 countries (last I checked it was the US, Myanmar, and Liberia). It becomes difficult for us who aren't American to determine what temperature the person is talking about. That's the whole point of the metric system. To standardize everything, and so someone isn't completely confused when you say 70 degrees.

Re:Shameless karma whore (0, Offtopic)

DaveV1.0 (203135) | more than 6 years ago | (#23865649)

Nazis? I hate those guys /Dr.Jones

Re:Shameless karma whore (5, Funny)

halivar (535827) | more than 6 years ago | (#23864473)

Celsius is based on water temperature, and Fahrenheit is based on alcohol temperature. Ergo, Fahrenheit is WAY better than Celsius. QED.

Re:Shameless karma whore (5, Informative)

evdubs (708273) | more than 6 years ago | (#23864625)

Uhh.. no it isn't. According to wikipedia [wikipedia.org] , there are three "standard" temperatures you can use to calibrate your thermometer for a Fahrenheit scale.

1) 0F - the stable temperature of ice, water, and NH_4Cl
2) 32F - where water freezes
3) 96F - average body temperature

Alcohol is not used anywhere.

Re:Shameless karma whore (5, Funny)

mordenkhai (1167617) | more than 6 years ago | (#23865081)

I believe he is referring to the fact that alcohol was used, in large quantities, by the researchers while coming up with the system. In that regard it is heavily based on alcohol, and Cheetos too if memory serves, but there is again no Wiki reference.

Re:Shameless karma whore (4, Insightful)

Daimanta (1140543) | more than 6 years ago | (#23865215)

"3) 96F - average body temperature"

That's nuts! An AVERAGE temperature to calibrate a thermometer? That's the same thing as calibrating my speedometer in my car to the average speed of a laden swallow.

Re:Shameless karma whore (2, Funny)

TheBig1 (966884) | more than 6 years ago | (#23865609)

African or European?

Re:Shameless karma whore (1)

Daimanta (1140543) | more than 6 years ago | (#23865761)

I don't know!

Waaaaaaa [CARRIER LOST]

Re:Shameless karma whore (1)

maxume (22995) | more than 6 years ago | (#23865911)

What do you think the temperature in the ice bath is?

Re:Shameless karma whore (4, Interesting)

4D6963 (933028) | more than 6 years ago | (#23865955)

"3) 96F - average body temperature"

That's nuts! An AVERAGE temperature to calibrate a thermometer? That's the same thing as calibrating my speedometer in my car to the average speed of a laden swallow.
Reminds me that when the metre was created it was so that the Earth's circumference would be 40,000,000 metres. And since then we measure the Earth's circumference in metres (well, kilometres), and it's not 40,000,000. Go figure..

Re:Shameless karma whore (-1, Redundant)

Anonymous Coward | more than 6 years ago | (#23865977)

"3) 96F - average body temperature"

That's nuts! An AVERAGE temperature to calibrate a thermometer? That's the same thing as calibrating my speedometer in my car to the average speed of a laden swallow.
Is that a European or African laden swallow?

Re:Shameless karma whore (0)

Anonymous Coward | more than 6 years ago | (#23866015)

Your car speedometer is calibrated using an average definition of both time and space, how is that any different?

Also temperature is a measure of mean energy, and even a specific energy can only be measured as an average, unless you have infinite time, or infinite space, both of which are hard to come by these days, what with the recession and all.

Re:Shameless karma whore (0)

Anonymous Coward | more than 6 years ago | (#23865825)

3) 96F - average body temperature

You might want to see a doctor about that.

Re:Shameless karma whore (1)

tom17 (659054) | more than 6 years ago | (#23864639)

No it is not, it was originally based on an ice & salt water mixture for the low end (0) and the body temperature for the high end (96).

Tom...

Re:Shameless karma whore (1)

BrianRaker (633638) | more than 6 years ago | (#23864975)

Since when was normal body temp 96F? Google-sama (and years of misspent youth in health and science classes) tell me it's 98.6F. ... unless we've started a new branch of cold-blooded humans, consisting mainly of politicians and murderers...

79.43 deg. Smurdley (1)

boristdog (133725) | more than 6 years ago | (#23864695)

Should be 79.43 degrees Smurdley

If you losers would get on the Potrzebie system we could avoid all this confusion.

Re:79.43 deg. Smurdley (1)

maxume (22995) | more than 6 years ago | (#23865939)

What happens when someone Knuth's a thread on the internet?

Wrong title (2, Insightful)

mangu (126918) | more than 6 years ago | (#23866107)

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.

Why are plants green? (2, Interesting)

Verteiron (224042) | more than 6 years ago | (#23864453)

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.

Re:Why are plants green? (0)

Anonymous Coward | more than 6 years ago | (#23864577)

> I've often wondered why chlorophyll isn't black for maximum sunlight absorption.

There's your answer -- they would cook.

They're green because they evolved with their particular chemical structure which was more than good enough, and no other structure has yet come around that would unseat the existing order.

Re:Why are plants green? (-1, Troll)

Anonymous Coward | more than 6 years ago | (#23864637)

There are actually multiple types of chlorophyll.

One type is yellow. It's easily produced and hardy, so it doesn't break down easily when the plant is unhealthy. But it's also not very efficient, partially for the reflectivity reasons you describe.

Another type of chlorophyll is dark blue. It's harder to produce, and quickly breaks down under adverse conditions. But it's a much better energy producer because it absorbs far more light.

And that is the reason why sick plants start to turn yellow. The blue chlorophyll is gone. On the other hand, the healthiest plants often turn a darker shade of green indicating a much higher quantity of blue chlorophyll.

Re:Why are plants green? (1)

JebusIsLord (566856) | more than 6 years ago | (#23865513)

Lots of plants that appear to be a different colour (red leaves, for example) also have other pigments such as carotenoids, which absorb certain wavelengths (green) and then reemit them as light usable by chlorophyl (orange, in this case).

Re:Why are plants green? (5, Informative)

solanum (80810) | more than 6 years ago | (#23866121)

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.

Re:Why are plants green? (2, Insightful)

Otter (3800) | more than 6 years ago | (#23864677)

Since I can't read the article, I'll speculate wildly. I've often wondered why chlorophyll isn't black for maximum sunlight absorption.

I'd imagine that the range of structures that can produce chlorophyll-like function is constrained, and that such structures with broader absorption either aren't possible or aren't evolutionarily reachable.

Re:Why are plants green? (0)

Anonymous Coward | more than 6 years ago | (#23866099)

Some interesting speculation is that oceans used to be purple, so there was no push to evolve green-absorbing chlorophyll.

http://www.rsc.org/chemistryworld/News/2005/October/06100502.asp

Son of shameless karma whore (3, Funny)

SputnikPanic (927985) | more than 6 years ago | (#23864685)

The green is reflected. Red and blue are absorbed. Why plants are green [msu.edu]

Re:Why are plants green? (1)

Ricardo (43461) | more than 6 years ago | (#23865841)

This was only explained to me once, but Ill try.
Chlorophyll molecules have at their focal point, ONE (big - compared to the other atoms) magnesium atom. Imagine it looks (sort of) like a dead scorpian on its back (the magnesium atom is at the head) at the energy it absorbs increases, the tail tip curls up til it touches the "head" and releases all the energy built up. OH - MAGNESIUM IS GREEN BTW. Most of the molecule is not green, but the m olecule is usually made to face the green head outwards (while laying on its back as it were). Hope this helps. this is one of those things where the natural solution is INCREDIBLE COOL. To all the biochemists who are cringing at my terrible lay-explaination - I apologise proifusley.

Or in Celsius (4, Insightful)

ObsessiveMathsFreak (773371) | more than 6 years ago | (#23864469)

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.

Re:Or in Celsius (2, Insightful)

moore.dustin (942289) | more than 6 years ago | (#23864507)

Obviously not.

Re:Or in Celsius (4, Insightful)

bucky0 (229117) | more than 6 years ago | (#23864597)

>Honestly, it really is worth the effort to switch.

Really? I'm a physicist and spend all my professional time working in m/s/kg units, but outside of that, what does it matter? We changed over the easier things, but the bit that's left (espcially feet/inches) don't justify the amount it would cost us to retool everything to use metric.

I never did get the obsession other people have with the units we use in the states.

Re:Or in Celsius (5, Insightful)

Applekid (993327) | more than 6 years ago | (#23864853)

I never did get the obsession other people have with the units we use in the states.
It's merely a point of contention for the "we're right, you're wrong" nationalistic crowd. Same with dates: MM/DD/YYYY, DD-MM-YYYY, YYYY.MM.DD, so on and so on.

I'm sure a war or two has been fought over whether toilet paper should be hung in the proper overhand fashion or the grotesque underhand abomination.

Re:Or in Celsius (1, Insightful)

corsec67 (627446) | more than 6 years ago | (#23865279)

YYYY.MM.DD

That is the only one that actually makes sense, since the rest of our numbering systems, including time, are big-endian. I happen to like a certain 13 month calendar [newearthcalendar.com] as well, so that would be MM from 01 to 13, and DD from 01 to 28, or to 35 in a leap year.

Re:Or in Celsius (0, Flamebait)

geekoid (135745) | more than 6 years ago | (#23865817)

There are reason for the directional difference between the dym and the hms

Of course, somebody so dim they can't see why the 13 month calendar can not work isn't likely to bother to understand why things are the way they are before thinking about changing them.

Hey, I can understand units, but don't mess (3, Informative)

DRAGONWEEZEL (125809) | more than 6 years ago | (#23865321)

with hanging toilet paper! It's over the top, Like it or not! Allways and everywhere unless your some kind of freaking psychopath!

Re:Or in Celsius (1)

geekoid (135745) | more than 6 years ago | (#23865721)

Overhand, duh. Hang it underhand, and people can scrape the paint from behind the sheet with their finger nails by accident.

Re:Or in Celsius (5, Insightful)

Hatta (162192) | more than 6 years ago | (#23865847)

YYYY-MM-DD(ISO 8601) is the only correct format. When you specify dates in that format, you can sort things chronologically simply by sorting them alphanumerically.

Re:Or in Celsius (5, Insightful)

vajaradakini (1209944) | more than 6 years ago | (#23865089)

Yes, clearly everything runs smoothly when people work in different units. Nothing could ever go wrong. Nobody could spend millions on a probe only to smash it into a planet instead, right? [wikipedia.org]

Sometimes it's worth an inconvenience...

Re:Or in Celsius (4, Insightful)

Anonymous Coward | more than 6 years ago | (#23865145)

Because it makes it very difficult to communicate things like that with Americans. How would you like it if you did a lot of business with Europe, but they still used cartwheels, furlongs, leagues, and all that stuff? The problem is communication. The rest of the world has seen value in the metric system and switched. But we have a huge problem in a very large country refuses to switch, necessitating the need to artificially extend the life of an archaic system of units.

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.

Re:Or in Celsius (1)

geekoid (135745) | more than 6 years ago | (#23865235)

We where going to be metric by now, but Reagan killed it.

I think global standards are good, and more important the more connected we get.
Retooling would be the cost it was in the 70's and 80s. Many factories produce both already.

OTOH, it's not worth the pissing match.
I notice England doesn't get a lot of crap over it's Pints.

Re:Or in Celsius (1)

Duradin (1261418) | more than 6 years ago | (#23864655)

Celsius is too wussy for climates with real weather.

'Round here 32F can be shorts, t-shirt and sandal weather. OC just sounds too cold for such a warm day.

Sure, eventually Celsius catches up but that point tends to fall outside of standard human operational temperature range.

On the other end Celsius just wouldn't work since it is traditional that the temperature is the same as the humidity after about 65F during road construction season.

Re:Or in Celsius (2, Interesting)

arb phd slp (1144717) | more than 6 years ago | (#23865003)

Celsius is too wussy for climates with real weather.

'Round here 32F can be shorts, t-shirt and sandal weather. OC just sounds too cold for such a warm day.

Sure, eventually Celsius catches up but that point tends to fall outside of standard human operational temperature range.
When I lived in Finland, in winter the temps were frequently -35. That's Celsius and Fahrenheit; it didn't matter.

Re:Or in Celsius (1)

geekoid (135745) | more than 6 years ago | (#23865735)

Apparently the people on slashdot or so easily confused, they might think you mean Kelvin.

Re:Or in Celsius (1)

dwye (1127395) | more than 6 years ago | (#23865865)

Actually, in the REAL Celcius scale, invented and used by the REAL Celcius, your 32F is 100. As it warms up to boiling water, the temeperature value decreases to zero.

Which is why I always call it Centigrade. Naming it after an idiot like that is not merely stupid, it is wrong, as it gives immortality to someone how should remain in obscurity.

Better, use K all the time, until the world is familiar enough with Kelvin they can think in it.

In other news, Trees bloom in 74.5 'Oxen' (0, Redundant)

unity100 (970058) | more than 6 years ago | (#23864487)

there. we have another outdated, ancient unit of measure in this thread now. heads of oxen.

pretty thin science... (5, Interesting)

MollyB (162595) | more than 6 years ago | (#23864573)

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?

Re:pretty thin science... (1)

edschurr (999028) | more than 6 years ago | (#23865531)

If that isn't a quote gotten by Richard Harris of the NPR piece directly, then it may be from "Leaves resist temperature extremes regardless of the weather" by Heidi Ledford who is probably summarizing "Subtropical to boreal convergence of tree-leaf temperatures" by Brent R. Helliker and Suzanna L. Richter, in addition to adding something about the authors' motivations.

Jesus F Christ (3, Interesting)

Moraelin (679338) | more than 6 years ago | (#23865677)

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.

Re:pretty thin science... (1)

mapkinase (958129) | more than 6 years ago | (#23865885)

How did this make it to Nature?
I take it as a rhetorical question.

Re:pretty thin science... (2, Informative)

philspear (1142299) | more than 6 years ago | (#23865899)

A special kinship with trees?!? How did this make it to Nature?

It didn't, it made it into NPR.

The abstract for the nature article:

The oxygen isotope ratio (18O) of cellulose is thought to provide a record of ambient temperature and relative humidity during periods of carbon assimilation1, 2. Here we introduce a method to resolve tree-canopy leaf temperature with the use of 18O of cellulose in 39 tree species. We show a remarkably constant leaf temperature of 21.4 2.2 C across 50 of latitude, from subtropical to boreal biomes. This means that when carbon assimilation is maximal, the physiological and morphological properties of tree branches serve to raise leaf temperature above air temperature to a much greater extent in more northern latitudes. A main assumption underlying the use of 18O to reconstruct climate history is that the temperature and relative humidity of an actively photosynthesizing leaf are the same as those of the surrounding air3, 4. Our data are contrary to that assumption and show that plant physiological ecology must be considered when reconstructing climate through isotope analysis. Furthermore, our results may explain why climate has only a modest effect on leaf economic traits5 in general.

So it made it into Nature because their results challenge an apperantly widely held assumption used in determining global warming... I think? I'm no ecologist/arborologist/whatever science is involved here. But it's actual science.

Re:pretty thin science... (1)

puff3456 (898964) | more than 6 years ago | (#23865989)

Absolutely, not only is the entire concept that a biological reaction occurs best at a specific temperature a given (if not stupidly obvious), the "discovery" is just another eco feel-good science project that basically tries to humanize plants by showing that they like certain temperatures just like us. Hardly news worthy, perhaps useful as a 5th grade science-fair project to teach certain fundamentals about biology.

70Deg K DAMN thats HOT!! (-1, Redundant)

Anonymous Coward | more than 6 years ago | (#23864673)

70Deg K DAMN thats HOT!!

forget geothermal-- how about aborealthermal..... (1)

way2trivial (601132) | more than 6 years ago | (#23864721)

run your house cooling lines right into the trunk baby....

70 degrees sounds kinda sweet-- better than running the rods 150 feet underground...

And I grow... (5, Funny)

sidnelson13 (1309391) | more than 6 years ago | (#23864789)

... when placed into moist locations. Give me five!

Ok, no good comes from watching Scrubs.

Humans are 98Â but prefer 72Â (4, Interesting)

booch (4157) | more than 6 years ago | (#23865331)

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.

Re:Humans are 98Â but prefer 72Â (1)

booch (4157) | more than 6 years ago | (#23865413)

OK, who changed my degree symbols into hatted A's (Â)? I actually cut and pasted the degree symbol from the article title. That doesn't work, nor does ° or °.

Ouch (1)

Aegis Runestone (1248876) | more than 6 years ago | (#23865529)

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.

Only an overly pendacit (-1, Troll)

geekoid (135745) | more than 6 years ago | (#23865675)

fuck who gets off on stupid shit would complain about there not being an F after 70 degrees.

What a bunch of fucking whiners.
Here is a clue,this site is American centric.

Re:Only an overly pendacit (1, Troll)

Maxo-Texas (864189) | more than 6 years ago | (#23865807)

Are you saying you don't get an F for what they think?

I ... C.

I'm not understanding (1)

overshoot (39700) | more than 6 years ago | (#23865863)

The Mississippi Delta country this time of year runs overnight lows in the 85F range or higher and dew points nearly as high, so evaporation is not going to get leaves down to 70F or anywhere near it.

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.

Just another... (1, Troll)

pchoppin (864344) | more than 6 years ago | (#23865949)

...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. [greenprophet.com]

When will it end?
Load More Comments
Slashdot Login

Need an Account?

Forgot your password?
or Connect with...

Don't worry, we never post anything without your permission.

Submission Text Formatting Tips

We support a small subset of HTML, namely these tags:

  • b
  • i
  • p
  • br
  • a
  • ol
  • ul
  • li
  • dl
  • dt
  • dd
  • em
  • strong
  • tt
  • blockquote
  • div
  • quote
  • ecode

"ecode" can be used for code snippets, for example:

<ecode>    while(1) { do_something(); } </ecode>