Study based on fossil sloth dung found in desert caves and packrat middens
From the US Geological Survey, because doing mapping and boundary lines are sooo yesterday:
Uncertain Future for Joshua Trees Projected with Climate Change
FLAGSTAFF, Ariz. — Temperature increases resulting from climate change in the Southwest will likely eliminate Joshua trees from 90 percent of their current range in 60 to 90 years, according to a new study led by U.S. Geological Survey ecologist Ken Cole.
The research team used models of future climate, an analysis of the climatic tolerances of the species in its current range, and the fossil record to project the future distribution of Joshua trees. The study concludes that the species could be restricted to the northernmost portion of its current range as early as the end of this century. Additionally, the ability of Joshua trees to migrate via seed dispersal to more suitable climates may be severely limited.
“This is one of the most interesting research projects of my career,” said Ken Cole, a USGS ecologist and the study’s lead author. “It incorporated not only state-of-the-art climate models and modern ecology, but also documentary information found in fossils that are more than 20,000 years old.”
By using fossil sloth dung found in desert caves and packrat middens — basically, the garbage piles of aptly named packrats — scientists were able to reconstruct how Joshua trees responded to a sudden climate warming around 12,000 years ago that was similar to warming projections for this century. Prior to its extinction around 13,000 years ago, the Shasta ground sloth favored Joshua trees as food, and its fossilized dung contained abundant remains of Joshua trees, including whole seeds and fruits. These fossil deposits, along with fossil leaves collected and stored by packrats, allowed scientists to determine the tree’s formerly broad range before the warming event.
The study concluded that the ability of Joshua trees to spread into suitable habitat following the prehistoric warming event around 12,000 years ago was limited by the extinction of large animals that had previously dispersed its seeds over large geographic areas, particularly the Shasta ground sloth. Today, Joshua tree seeds are dispersed by seed-caching rodents, such as squirrels and packrats, which cannot disperse seeds as far as large mammals. The limited ability of rodents to disperse Joshua tree seeds in combination with other factors would likely slow migration to only about 6 feet per year, not enough to keep pace with the warming climate, Cole and his colleagues concluded.
The Joshua tree, a giant North American yucca, occupies desert grasslands and shrublands of the Mojave Desert of California, Nevada, Arizona, and Utah; Joshua Tree National Park in California is named after this iconic species. The Joshua tree is known for its distinctive shape and height of up to 50 feet.
Results of the study, “Past and ongoing shifts in Joshua tree distribution support future modeled range contraction,” appear in a current edition of “Ecological Applications.” The research team included Kenneth L. Cole, U.S. Geological Survey; Kirsten Ironside, Northern Arizona University; Jon Eischeid, NOAA Earth Systems Research Laboratory; Gregg Garfin, University of Arizona; Phillip B. Duffy, Lawrence Livermore National Laboratory and University of California; and Chris Toney, USDA Forest Service.
So the decline of the Joshua tree began 13,000 years ago when the poor old Giant Ground Sloth died out as the last ice age ended? It’s taken 13,000 years for the Joshua tree, in the American SW, to decline and now they’re worried. Give me strength. Didn’t Darwin have something to say about this kind of thing?
I live in the high desert of SE Arizona. at about 5000 feet. There are a few Joshua trees in the immediate neighborhood. It looks like about half of them were killed by the record cold temps we had this last winter. Along with what appears to be EVERY Cholla cactus. The Cholla has a wider elevation range than the Joshua tree. From 2000 to 7000 feet. The Joshua elevation range is from 2000 to 6000 feet. I would be more worried about the cold.
Other plants killed in the cold snap include, EVERY Palm tree (some have grown to over 50′ tall), EVERY Oleander bush and a few other warm climate plants.
LOL!
I live in Joshua Tree country.
The biggest threat to the trees…Land use.
However, they are protected now. You can’t dig one up without a permit.
Given that it will hit 115F plus in the summers and the low teens in the winter, I doubt they would notice a small shift in average temperature. They’re pretty hearty planty-treeish things.
I have noticed that they grow more fruit/seeds during wet years though. Imagine that. I didn’t see any mention of precipitation in the article at the USGS.
One creature that has departed from the Antelope Vally, is, namely, the antelope.
If they did eat the fruits, they had a long migration path. Sadly, they’re no longer present. They wouldn’t cross the train tracks apparently and eventually migrated elsewhere, died out, or were killed by people shooting from the trains. (Think wild west days.)
On a side note, the U2 album ‘Joshua Tree” and song “Where the Streets Have No Name” were inspired by a drive along the CA I-14 freeway. (The street exits were all letters at the time.) N-S are streets are numbers, E-W streets are letters, the cities have added names since then.
It really is a shame that the current state of science permits this kind on nonsense. Really…..at 40 yrs into the future you can say with certainty that seed dispersal will be limited to a tortoise like 6 ft per year, and quick as a rabbit global warming is gonna run joshua tree down and kill him. Wow, now we have a verified speed for global warming. Something a little bit more than 6 ft yr. How much did that cost me ? Brilliant. What the hell has happened to science. I have never in my life seen such BS dressed up as the truth. When this whole thing comes crashing down, the backlash for legitimate scientists won’t be pretty, and they have my sympathies. The few that are left that is.
I wondered how many comments I would read before I saw what Willis mentioned: the glaring discrepancy that the sloth became extinct 13,000 years ago, but the climate didn’t change until 12,000 years ago. I thought something was funky there.
The story is filled with all the usual definitive media speak: “likely… future modeled range contraction…state-of-the-art climate models…warming projections”.
My opinion: I can’t believe this guy gets paid by the USGS to study and then publish this conjecture trash.
kadaka (KD Knoebel) says:
March 25, 2011 at 2:54 pm
Study based on fossil sloth dung…
This is the point where I had to stop for a giggle break.
Uh, “FIFO” – “Feces In, Feces Out”.
🙂
…not just a climastrologist…but an ecostrologist as well…
I recently drove from Phoenix to Las Vegas and was pleasantly surprised to see the forest of Joshua Trees in betwixt. I can’t speak to the ‘science’ of what is modeled, but as of March 2011, the specimens in the forest looked very healthy indeed.
RE: “I think the Joshua trees have cooling to worry about”
Yep. The SW US has seen better days. The relatively warm and benign period which began during the 1800s (and led the 20th century boom) may be kaput.
Jit said on March 25, 2011 at 4:16 pm:
Says above that the Shasta ground sloth went extinct around 13,000 years ago. During the Last Glacial Maximum, due to the the land bridge that appeared between what-is-now Russia and Alaska across the Bering Strait (that area called Beringia), the “native” human populations crossed over the land bridge and started populating the Americas about 16,500 years ago or less.
Therefore, it’s plainly obvious that humans were what killed the sloths. And since climate change (the glaciation) allowed the humans to be in the sloth’s territory, where they obviously killed off the sloths, that makes the Shasta ground sloth a species that was (ultimately) killed off by climate change.
Of course “climate change” is used as “global warming” by the (C)AGW-pushers, they don’t want “climate change” to represent a global cooling event.
So I guess they’ll claim that if there hadn’t been global warming thus the land bridge hadn’t gone away, all those migrating humans would’ve gone back to Russia and the sloths wouldn’t be extinct!
t stone,
I can’t believe that I spend even a nanosecond of my day working to pay for this s***. This is the kind of thing where I’d like to march into Congress, take the budget, and mark a big, red line through this particular line item.
Willis, it sounds like what they are saying is that they used the sloth dung from 13000 years ago to determine the pre-warming extent of the trees, and then looked at the post-warming extent after the 12000-years-ago warming event. I’m highly suspicious about the value of this whole study, but I’m not sure we can say the timing of these two numbers is inconsistent.
“On 6th August 1964, one of the greatest crimes against Nature was committed when the oldest living inhabitant on Earth was unwittingly killed. WPN-114, previously known to its affectionate admirers as Prometheus, was a bristlecone pine tree that, posthumously, was discovered to have been at least 5000 years old.
SO this fellow actually “murdered” a tree? Is that even possible? If Gaia is real, I hate to see what the afterlife has in store for me, given the amount of grass, trees and the like I’ve murdered over the years. Not to mention all of those soybean plants on the old farm!
I don’t trust anyone’s C14 dates. Especially during the Pleistocene/Holocene transition. But lemme see if I’ve got this straight.
We are looking at two ‘Dryas Stadial’ periods, or ice ages. As I understand it, the big one ended about 15,000 years ago. Temps had begun to warm up to temps similar to today, when something about 12,900 YA knocked the world back into ice age conditions for another 1,300 years, or so. The evidence so far, implies that the shorter ice age, or Younger Dryas Cooling may have been triggered by an as yet to be defined kind of impact event. Perhaps the clouds of dust, and debris, from the breakup of a giant comet.
Be that as it may, the YD trigger, what ever it was, was a mass extinction event. The Giant sloth was apparently a victim of that event. And as far as I know there have been no fossils of them recovered from above the YD boundary layer.
It would seem that the event that killed all the giant animals like the giant sloth, the mastodons, and woolly mammoths, was probably also the trigger for a return to ice age conditions. So the extinction event coincides with a sudden cooling. Not a warming trend.
The Megafauna weren’t killed by climate change. They were killed by what ever triggered that change, and knocked the world back into an ice age that lasted more than a millennium. And there is nothing in the climate we see today that bares any resemblance to what was experienced at the Pleistocene/Holocene transition.
Finding Joshua tree seeds in sloth dung is only significant to the story because it shows that the trees have lost an important seed dispersal species. But they’ve been doing ok without the help of the Giant Sloth for 13,000 years now.
Never mind the Joshua trees. If the climate really is changing, and they begin to die out because they can’t change their range fast enough to keep up with the climate, we can be sure they will not have a problem. There are far more tree huggers alive today to scatter seeds over a wider range than the sloths ever could. The Joshua trees are still with us. No worries there.
Understanding what wiped out the Clovis culture, and more than 35 genera in North America, including probably the very sloth that made the poo the USGS is so exited about is the important question.
If we can’t say what happened then, how can we be sure it won’t happen again, but this time to us?
Models again, with no predictive value. The very definition of pseudoscience. This is 90% speculation and 10% actual data and science. You didn’t used to be able to publish such stuff in biology, but now that is where the money is.
Real biology is severely harmed by consequent lack of funding, by distraction from actual causes and by black-is-white inversions of facts and truth.
Ay-yi-yi
I (no relation to Ken, but I work there too) have to roll my eyes at some of the press releases that come from my organization. Seems like we’re trying to out-panic Discovery mag, SciAmerican, and the rest of the babbling hordes.
Back in the Clinton years, all the gummint biologists/ecologists/etcs got swept into the National Biological Service, relieving the Fish & Wildlife, Park Service, USGS, BLM, and many others of their cost and overhead. Not to mention bogus research (all god’s critters are doomed because of MAN)
Gingrich & Co. “contracted with America” and abolished NBS, but they recycled the eco-panickers to fed agencies and the USGS got stuck with the Biological Division.
It has not been a good fit. The Geology and Water folks still try to document and understand earth history. The bio-folks continue to ignore evolution and adaptation while asserting that all living things are DOOMED due to MAN.
Fercryinoutloud, the poley bears survived the Holocene Optimum 6000 years ago, so they can certainly survive the Modern Warm. Fossils are much better evidence that models. Much, much better.
Retirement is lookin’ good, dude.
Charlie Foxtrot says:
March 25, 2011 at 4:45 pm
“The problem, obviously, is that the rodents that we are using to disperse the seeds need to be replaced by faster rodents. What worked for the last 12,000 years is simply not good enough anymore.”
How do they know that global warming won’t cause faster rodents?
Thanks to everyone. I was ROTFLMAO. I needed that.
“By using fossil sloth dung…”
I didn’t know they used NASA GISS Model E…
/sarc
Ggrow some joshua trees in a greenhouse in the desert.
Raise the co2 to 600 ppm and raise the temp to their projected “AGW temp”
Let’s see what the trees do.
I read this at work, ruined a keyboard and wasted a good swallow of coffee. I kept thinking I had somehow clicked on quote of the week or the Friday funny! Strange, if I redo the study with a different climate model and get no threat, that will be a publishable paper now thanks to this pile of sloth manure.
Lady Life Grows says:
March 25, 2011 at 6:48 pm
Models again, with no predictive value.
The only reason they can do these models is because they have excess computer power to play with. Copernicus actually had to spend years working things out in hand, and using his mind.
I’m becoming ashamed I spent the last 35 years trying to make computers spin faster. But then I also fee the same way about spreadsheets. Management by spreadsheet is a precursor of climate “modeling”.
I do think he hath slung more than sloth dung.
RE: The research team used models of future climate, an analysis of the climatic tolerances of the species in its current range
Well the model of future climate without snow didn’t quite pan out for the UK, so why should I believe this one?
http://www.independent.co.uk/environment/snowfalls-are-now-just-a-thing-of-the-past-724017.html
Carl Bussjaeger says:
March 25, 2011 at 3:54 pm
“Clearly these trees cannot be the product of Darwinian evolution. Creation science is proven; we just attributed it to Jehovah, when it was actually Gaia.”
Gaiahova.
U.S. Geological Survey ecologist Ken Cole. What a dim bulb. The giant packrat ape has spread joshua trees all over the world! The joshua trees’ range has increased not decreased. This overpaid scout should be made to visit every city and town garden. Catologe the location of every plant and the condition that it lives in to establish the plants true range. pg