Powerful mathematical model greatly improves predictions for species facing climate change

Dec 03, 2011

UCLA life scientists and colleagues have produced the most comprehensive mathematical model ever devised to track the health of populations exposed to environmental change.

The research, federally funded by the National Science Foundation, is published Dec. 2 in the journal Science.

The team's groundbreaking integral projection model, or IPM, unites various sub-disciplines of population biology, including population ecology, quantitative genetics, , and life-span and offspring information, allowing researchers to link many different data sources simultaneously. Scientists can now change just a single variable, like temperature, and see how that affects many factors for a population.

"This is one of the most innovative and holistic models, because it unifies so many sub-fields of ecology and genetics into one ," said study co-author Robert Wayne, a UCLA professor of ecology and , who led the UCLA research team. "Traditionally, we have studied just a few ecological parameters at a time, like how much food there is or how the environment will change over time, and how that relates to . Here, we are analyzing everything at once."

Among the researchers' major findings with the IPM is that gradual, sustained change in an environment over time — a gradual increase in temperature, for example — has a greater impact on the species in an ecosystem than fluctuating changes.

"If we change the total environment, such as temperature, we change a whole suite of characteristics for a species, including viability, fertility, population size, body size and generation length," Wayne said.

The new model could therefore be of great use in predicting the complex ecological impacts that could result as Earth's temperature gradually rises as a result of high carbon dioxide emissions entering the atmosphere and oceans.

"Probably much of the tundra in the high Arctic will disappear with global warming," Wayne said. "Since this is a very general model, it can be applied to any population, from a polar bear to a wolf to a beetle, even plants. We want to use this model to make predictions about populations that are in dire situations, as their environments will be changing quickly."

Just as physicists are searching for a unified field theory to bring the physics of the very large in harmony with the physics of the very small, the IPM "is the version in ecology and population genetics of a similar unified theory," Wayne said.

The collaboration that led to the new model followed a fortuitous meeting between Wayne and collaborator Tim Coulson, a professor of population biology at Imperial College London. Following a talk by Coulson at UCLA , Wayne and his research team combined their decades of expertise on the wolf population in Yellowstone National Park with Coulson's expertise in applied mathematics — and the most comprehensive ecological model was born.

Wolves were first introduced into Yellowstone in 1995 to control the overpopulation of elk and bison and to restore deteriorated forests. These wolves were closely monitored with radio collars in the years that followed, generating a vast array of detailed data. The effects they generated in the park — known as a trophic cascade — allowed many species, such as songbirds, beavers and grizzly bears, to thrive again as the elk and bison populations diminished.

"A critical issue for us is how these wolves will survive into the future," Wayne said. "This model addresses that issue in a comprehensive way by taking in so many components of population health."

The model also explains the persistence of the grey coat color in Yellowstone wolves, despite the fact that the gene for black coat color is dominant. Using genetic data collected in Wayne's laboratory, the IMP revealed that wolves who possessed two different versions of the coat-color gene, known as heterozygotes, lived longer and had more offspring than wolves who had two identical genes for coat color.

This example demonstrates the power of the new model, as it can make sense of seemingly unrelated information on population genetics and life history and generate a clearer understanding of an observed coat-color phenotype, and beyond that, the implications for survival of these animals in a complex ecosystem.

By using a model that could generate more accurate predictions, "We could potentially build scenarios predicting whether a species has no chance of recovery, and this could lead protection efforts," Wayne said.

"We are not very effective at stopping global warming, but perhaps we could identify ways to alter or enrich habitats to mitigate environmental effects," he added.

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Provided by University of California - Los Angeles

4.4 /5 (8 votes)

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User comments : 15

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Vendicar_Decarian
1.4 / 5 (9) Dec 03, 2011
And again we find no Denailists spouting their dishonest nonsense on this thread.

What's wrong boys? Finally found yourself a real Job?
fleem
5 / 5 (6) Dec 03, 2011
And again we find no Denailists spouting their dishonest nonsense on this thread.

What's wrong boys? Finally found yourself a real Job?


Spoken like a true scientist.
Shelgeyr
2.1 / 5 (7) Dec 03, 2011
Complexity does not equal accuracy, and I'm more than a bit skeptical about about a model claiming to be both general enough that "it can be applied to any population, from a polar bear to a wolf to a beetle, even plants" and it being "one of the most innovative and holistic models, because it unifies so many sub-fields of ecology and genetics into one predictive model..."

These people have too much faith (and "faith" it is) in their models.

Once again they try to "prove" their model's predictive powers by comparing it to historical data (the wolf example), which is such a known logical flaw that this far down the road it should simply just be considered fraud.

The headline claims the model "greatly improves predictions for species facing climate change". Really? How do they know? Have they tested ANY of their predictions? Where's the data showing improvement? Their data had better show results covering the range from apples to zebras, else they should all be fired.
_nigmatic10
3.4 / 5 (5) Dec 03, 2011
The final model looks like this .....
1 - 1 = 0

A break through, im sure.

And again we find no Denailists spouting their dishonest nonsense on this thread.

What's wrong boys? Finally found yourself a real Job?


Sadly, to certain gw zealots, a denialist is anyone that doesn't believe as they do. When those believers speak, it often hurts more than helps their cause.
bluehigh
1.7 / 5 (11) Dec 03, 2011
Vendi, If only I could find a rational argument with which to engage you on this subject, alas none seems to exist.

Oh I got one ... more PlayStation models with no scientific evidence .. damn, some fools beat me to it!!
cave_painter
4.2 / 5 (5) Dec 03, 2011
And again we find no Denailists spouting their dishonest nonsense on this thread.

What's wrong boys? Finally found yourself a real Job?


Vendicar, I have yet to see you post an actual argument on any of these threads. I only notice who you are because you only respond with self aggrandizing gibberish.

Please, enlighten me. I'm concerned that modellers forget that the universe is the universe, and models are models. So was Feynman, for that matter. The universe has the great advantage of being. It just is. It doesn't have to know itself and carefully include and balance factors within itself. It is.

Why is skepticism of modeling so unintelligent and abhorrent that those concerned should be required to refrain from engaging in public discussion? How do you feel your models become more rigorous in an intellectual environment sterile of contradictory points of view?

Can you write? Can you reason? I've been looking for a lucid argument posted by you, and I have yet to find one.
axemaster
2.3 / 5 (6) Dec 03, 2011
The final model looks like this .....
1 - 1 = 0

A break through, im sure.

Oh? Is that all the math you know? Good work.

Sadly, to certain gw zealots, a denialist is anyone that doesn't believe as they do. When those believers speak, it often hurts more than helps their cause.

Global warming isn't a belief, it's a proven fact. So we don't believe in it. The denialists are the believers (i.e. those without any actual evidence to back up their position). Until you people understand that "feelings" and "opinions" are worthless compared to facts and data, there is very little to discuss.
axemaster
4 / 5 (4) Dec 03, 2011
Please, enlighten me. I'm concerned that modellers forget that the universe is the universe, and models are models...

These are reasonable objections, so I'll try to answer as best I can. These models are usually tested by running them against real world climate and weather data. If one inputs the initial conditions of say 1980, and then the model gives a good approximation of today's climate, then generally that's a good indication. So there is feedback.

Why is skepticism of modeling so unintelligent and abhorrent that those concerned should be required to refrain from engaging in public discussion? How do you feel your models become more rigorous in an intellectual environment sterile of contradictory points of view?

Skepticism isn't unintelligent or abhorrent - however most of the people criticizing this stuff aren't skeptics. Skepticism requires an understanding of the subject, and the ability to rationally argue against it. Would answer last part, but word limit...
axemaster
5 / 5 (2) Dec 03, 2011
How do you feel your models become more rigorous in an intellectual environment sterile of contradictory points of view?

It really isn't, though perhaps it looks like that from the outside. Everyone wants accuracy, so I can assure you that if a bad model came out, it would immediately be criticized. Think of climate scientists more like engineers:

They are trying to understand a problem, and their understanding is like a tower. They don't just want to pile things up on the tower - it needs to be strong. So if someone tries to insert a bad girder, they get mad - they don't want their tower supported by shoddy work.
Doug_Huffman
3 / 5 (4) Dec 03, 2011
The final model looks like this; 1 - 1 = 0
Very good. You are smarter than you thought and smarter than your critics. An analytic statement is not falsifiable and is a tautology containing the same episteme on the left and right sides.

An analytic tautology is the goal of ad-hockery, the piling on of ad hoc hypotheses as an argument against falsification.

This professor and his team are victims of the Ludic fallacy, the faith that reality is consistent on all scales. The truth is that reality is fractally grained and only fools indulge in blind inductive inference.
axemaster
3 / 5 (4) Dec 03, 2011
The final model looks like this; 1 - 1 = 0
Very good. You are smarter than you thought and smarter than your critics. An analytic statement is not falsifiable and is a tautology containing the same episteme on the left and right sides.

Ah... I might be in love with you... I haven't laughed that hard in a while.
Shelgeyr
2.5 / 5 (8) Dec 03, 2011
@axemaster said:

Global warming isn't a belief, it's a proven fact.


No it isn't. That's a false statement, en excelsis.

...Until you people understand that "feelings" and "opinions" are worthless compared to facts and data, there is very little to discuss.


You are SO projecting.
ryggesogn2
1.7 / 5 (11) Dec 03, 2011
How was it validated?
_nigmatic10
1 / 5 (2) Dec 04, 2011
The final model looks like this .....
1 - 1 = 0

A break through, im sure.

Oh? Is that all the math you know? Good work.

Sadly, to certain gw zealots, a denialist is anyone that doesn't believe as they do. When those believers speak, it often hurts more than helps their cause.

Global warming isn't a belief, it's a proven fact. So we don't believe in it. The denialists are the believers (i.e. those without any actual evidence to back up their position). Until you people understand that "feelings" and "opinions" are worthless compared to facts and data, there is very little to discuss.


If the end result is zero then that is all the math they need. Also, i did not say gw wasn't a fact. Of course, the contribution by man and the belief we can somehow reverse it never stops selling tickets to the side show.

Like i said, often, when they open their mouths, they do more harm than good. Thanks for proving that point.
tonche
1 / 5 (1) Dec 04, 2011
All animals physiology will adapt, 2 nd generation animals cn have conpletly different capABILITIES AND ADAPTAIONS that thier grandparents never had.