Climate change downsizing fauna, flora: study

Oct 16, 2011 by Marlowe Hood
Plants are seen in Paris in 2010. Climate change is reducing the body size of many animal and plant species, including some which supply vital nutrition for more than a billion people already living near hunger's threshold, according to a study released Sunday.

Climate change is reducing the body size of many animal and plant species, including some which supply vital nutrition for more than a billion people already living near hunger's threshold, according to a study released Sunday.

From micro-organisms to top predators, nearly 45 percent of species for which data was reviewed grew smaller over multiple generations due to , researchers found.

The impact of rapidly climbing temperatures and shifts in on body size could have unpredictable and possible severe consequences, they warned.

Previous work established that recent climate change has led to sharp shifts in habitat and the timing of reproductive cycles. But impact on the size of has received far less attention.

Jennifer Sheridan and David Bickford at the National University of Singapore looked at scientific literature on climate-change episodes in the distant past and at experiments and observations in recent history.

, they found, were unambiguous: past periods of rising temperatures had led both marine and land organisms to became progressively smaller.

During a warming event 55 million years ago -- often seen as an analogue for current climate change -- , bees, spiders, and ants shrank by 50 to 75 percent over a period of several thousand years.

Mammals such as and woodrats also diminished in size, by about 40 percent.

The pace of current warming, though, is far greater than during this so-called Palaeocene-Eocene Thermal Maximum (PETM).

A toad is seen in Borneo in July 2011. Climate change is reducing the body size of many animal and plant species, including some which supply vital nutrition for more than a billion people already living near hunger's threshold, according to a study released Sunday.

It, too, has begun to shrink dozens of species, the study found.

Among 85 examples cited, 45 percent were unaffected. But of those remaining, four out of five had gotten smaller, while a fifth got bigger.

Some of the shrinkage came as a surprise. "Plants were expected to get larger with increased ," but many wound up stunted due to changes in temperature, humidity and nutrients available, the researchers said.

For cold-blooded animals -- including insects, reptiles and amphibians -- the impact is direct: experiments suggest that an upward tick of one degree Celsius translates into roughly a 10 percent increase in metabolism, the rate at which an organism uses energy. That, in turn, results in downsizing.

The common toad, for example, has measurably shriveled in girth in only two decades, along with some tortoises, marine iguanas and lizards.

Overfishing has been blamed for decreased in both wild and commercially-harvested aquatic species, threatening the key source of protein of a billion people around the world, mainly in Africa and Asia.

But experiments and observational studies have shown that warming waters play a role as well, especially in rivers and lakes.

Birds -- including passerines, goshawks and gulls -- and mammals such as soay sheep, red dear and polar bears, have also trended towards less bulk.

Some of the most worrying changes are at the bottom of the food chain, especially in the ocean, where tiny phytoplankton and calcium-building creatures are dwindling in size due to acidification and the reduced capacity of warmer water to hold oxygen and nutrients.

Carbon pollution has probably locked in an additional 1.0 C increase in average global temperatures, and continued emissions of greenhouse gases could push up the thermometre another 4.0 to 5.0 C (7.4 to 9.0 F) by centuries end, according to the UN's Intergovernmental Panel on Climate Change (IPCC).

Because warming is occurring at unprecedented rates, "may organisms may not respond or adapt quickly enough", especially those with long generation times, the authors noted in an email.

"We do not yet know the exact mechanisms involved, or why some organisms are getting smaller while others are unaffected," they added. "Until we understand more, we could be risking negative consequences that we can't yet quantify."

The study is published in the peer-reviewed journal Nature Climate Change.

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talikarni
1.4 / 5 (21) Oct 16, 2011
This just goes to show this claimed global warming continues to be a business instead of science with the basis of facts. Look at the chain of facts: if CO2 was increasing as claimed, then plants would be growing faster and larger to compensate for the increased CO2. The faster growth and health of plants would mean an increase in population, health and size of the animals that rely on the plants for food. The increase in size and health of plant eaters would then go up the food chain.
So by stating plants and animals are getting smaller means that nature is compensating for any increase and actually proving a levelling out or slight decrease in CO2 levels, thus using its own information showing that this is not global warming. This story uses an opinion piece with cherry picked information and attempts to make it sound like facts.
kaasinees
3.1 / 5 (16) Oct 16, 2011
Most plant species do get "bigger" because of increased CO2. Many that we live off the opposite, read the article.
OvertOddity
4.1 / 5 (14) Oct 16, 2011
Wow, we have reality-deniers even on physorg...sad.
PinkElephant
5 / 5 (9) Oct 16, 2011
@talikami,

You must have never heard of the Keeling curve. Here, take a look:

http://en.wikiped...ng_Curve
Conner
4.6 / 5 (9) Oct 16, 2011
talikarni: Did you bother to actually read before posting?

Taken directly from the article: "Some of the shrinkage came as a surprise. 'Plants were expected to get larger with increased atmospheric carbon dioxide,' but many wound up stunted due to changes in temperature, humidity and nutrients available, the researchers said."
astro_optics
2.1 / 5 (11) Oct 16, 2011
Well I read the article...interesting, also checked the Keeling curve, according to the graph since the sixties the increase has been 70ppm or 0.007%, significant indeed. Also, it's interesting that he's abandoned the CO2 measuring in Antarctica would be interesting what results he would have got there...different air currents...different results! I'm guessing the results would have not fared favourably with the doctrine!
deepsand
3.4 / 5 (15) Oct 16, 2011
Also, it's interesting that he's abandoned the CO2 measuring in Antarctica would be interesting what results he would have got there...different air currents...different results! I'm guessing the results would have not fared favourably with the doctrine!

Of what material relevance to the extant observations?
PinkElephant
4.3 / 5 (12) Oct 16, 2011
@astro_optics,

The 'ppm' figure is with respect to atmospheric concentration. CO2 is a trace gas in the atmosphere. The 70 ppm increase for CO2 is actually a 22% increase relative to the low-point of 315 on the Keeling curve. Historical maximum over the past 400,000 years, until the last couple of centuries, was actually 280 ppm. So relative to that, today's nearly 390 ppm translates into a nearly 40% rise.
the results would have not fared favourably with the doctrine!
What doctrine would that be? The Mauna Loa series is merely the oldest-running such series. CO2 measurements have been kept all over the globe. The Keeling curve does not deviate from the global value.

http://en.wikiped...mosphere
Anda
3.7 / 5 (3) Oct 17, 2011
This story uses an opinion piece with cherry picked information and attempts to make it sound like facts.
... talikarni

Funny... That's what YOU do
DrSki
2 / 5 (4) Oct 17, 2011
Curious... I'm sure it has to do with the "NEW MATH", but how does 0.1degC over the past 100 years translate into 4-5degC in the next 88?
kaasinees
2.6 / 5 (10) Oct 17, 2011
climate change deniers still exist? shame :( they must live in a fantasy world..
R2Bacca
3 / 5 (4) Oct 17, 2011
This, of course, completely explains the Mesozoic era... [/sarcasm]

The problem with this study for me is it apparently ignores other pressures such as shrinking habitats, invasive species and the shifting of water resources toward cities and farmland. How about non-carbon pollution? Ocean acidification?

The Permian era saw a huge increase in temperatures , with a median temperature 2 degrees higher than present and a CO2 concentration of 900ppm, saw the rise of Meganeuropsis permiana, a 1-lb dragonfly-like insect with a wingspan of 30 inches.

Climate change is becoming a catch-all for second-rate science because the time it takes for these predictions to be shown as correct or incorrect is much longer than the lifespan of those who are researching it.

I'm not denying climate change here... I'm just questioning this study's results.
kaasinees
1 / 5 (3) Oct 17, 2011
The problem with this study for me is it apparently ignores other pressures such as shrinking habitats, invasive species and the shifting of water resources toward cities and farmland. How about non-carbon pollution? Ocean acidification?

These are all factors of the climate system.

The Permian era saw a huge increase in temperatures , with a median temperature 2 degrees higher than present and a CO2 concentration of 900ppm, saw the rise of Meganeuropsis permiana, a 1-lb dragonfly-like insect with a wingspan of 30 inches.

duh, what do you think this research is about?

Climate change is becoming a catch-all for second-rate science because the time it takes for these predictions to be shown as correct or incorrect is much longer than the lifespan of those who are researching it.

Climate change is becoming an abomination second-rate citizens
fixed
I'm not denying climate change here... I'm just questioning this study's results.

Which is good, but read
R2Bacca
4.2 / 5 (5) Oct 17, 2011
These are all factors of the climate system.

Diverting the Colorado River to provide water to Las Vegas is a climate system factor? Clearing land to make room for cities and towns ins a climate system factor? Invasive species hitching a ride in a container of bananas from South America is a climate system factor?

duh, what do you think this research is about?

Duh, this research is about species *shrinking* because of increasing temperatures. The example I cited is of a particularly *large* species which existed during a particularly warm period in earth's history.

Climate change is becoming an abomination second-rate citizens
fixed

Please spell and grammar check before submitting a post. I don't even know what you're saying here. I think you were trying to call me a "second-rate citizen" (which would be an ad hominem attack and against commenting policy), but I'm not sure.

Which is good, but read

Thank you for the suggestion, however I did read it.
kaasinees
1.9 / 5 (8) Oct 17, 2011
Diverting the Colorado River to provide water to Las Vegas is a climate system factor? Clearing land to make room for cities and towns ins a climate system factor? Invasive species hitching a ride in a container of bananas from South America is a climate system factor?

Climate system are mostly factors that influence climate. Read about climate system.
Duh, this research is about species *shrinking* because of increasing temperatures. The example I cited is of a particularly *large* species which existed during a particularly warm period in earth's history.


doh, read the article. no reading comprehension?

article:

Some of the shrinkage came as a surprise. "Plants were expected to get larger with increased atmospheric carbon dioxide," but many wound up stunted due to changes in temperature, humidity and nutrients available, the researchers said.
R2Bacca
4 / 5 (4) Oct 17, 2011
Climate system are mostly factors that influence climate. Read about climate system.
You didn't answer my questions. Read my questions.

doh, read the article. no reading comprehension?
I did. try pointing out what I missed. Read my comments.

Some of the shrinkage came as a surprise. "Plants were expected to get larger with increased atmospheric carbon dioxide," but many wound up stunted due to changes in temperature, humidity and nutrients available, the researchers said.


Have you ever attempted to grow a garden? Small variation in temperature has much much less to do with how well plants grow than does variation in nutrients. Read about fertilizer.

On a side note, it's really easy to just write "read about x" to try and demonstrate that the person you're arguing against has no clue what they're talking about. The problem is you're basing that argument on the assumption that I haven't read anything nor am I educated. Try a different tactic.
kaasinees
1.3 / 5 (10) Oct 17, 2011
You didn't answer my questions. Read my questions.

I did answer your question. I told you to read about climate systems.
All the factors you summed up go under the climate system.
The climate system influences climate.

My last post i waste on you.
Egnite
1.8 / 5 (5) Oct 17, 2011
R2Bacca, you should join the UN!! It's great to read some unbiased observations from a study which the majority would comment on with AGW (believer/denier) scripture. It seems most studies have to condemn CO2 before they will get paid which leaves other important contributing factors being overlooked.
R2Bacca
3.8 / 5 (5) Oct 17, 2011
My last post i waste on you.


So basically you admit that you have no real dog in the fight here. It's ok to storm off in a hissy fit when you're six years old, but it's more fun to act like a grown up.

I really don't see how I am wrong in pointing out that you can't just look at "shrinking species", compare it to a graph of recent temperature change and say "see, that's the reason why". The environment is just too complicated to draw conclusions like that based on such thin evidence.

If you take my Colorado River example, we are diverting water and nutrients from locations downstream that a higher biodiverity. Take away the nutrients and the species, on the average, will likely start getting smaller.

Invasive species choke out native plants, forcing them to exist in smaller areas, which only grow smaller as we continue expanding our cities. Think of fish in a small fishbowl.

And also, I never asked you to reply to my comment. You *chose* to do that yourself.
R2Bacca
4 / 5 (7) Oct 17, 2011
@Egnite - the climate change umbrella grows by the day. I take issue with scientists who just throw anything and everything under the umbrella. The game right now seems to be to find any possible tie to climate change and publish about it before anyone else does.

Climate Science has become the new Bible (when interpreted literally) where even the thinnest shred of evidence is perverted to make it fit with an strongly-held ideology even though there very well be a better explanation.

Edit-
But at the same time, please don't consider my comments "denialist"... Is the climate changing? Yes. Does man probably have something to do with it? Yes. Is climate change far overblown? Yes. Is the pop-culture nature of climate science to blame for some of the "climate smut" that's out there? YES.
Nerdyguy
5 / 5 (2) Oct 22, 2011
talikarni: Did you bother to actually read before posting?

Taken directly from the article: "Some of the shrinkage came as a surprise. 'Plants were expected to get larger with increased atmospheric carbon dioxide,' but many wound up stunted due to changes in temperature, humidity and nutrients available, the researchers said."


- Wait a minute, we're supposed to like read and stuff? But Rush Limbaugh already explained all this.

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