
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.
My reactions:
(1) This is a bunch of fossil sloth dung.
(2) I don’t give a coprolite.
PS looks like Ken Cole will not have a job in a few years time with science like this
You silly people, don’t you know that the giant ground sloths drove equally giant ATVs all over the desert, belching out CO2 and strewing Joshua tree seeds hither and yon? The silly creatures were the engineers of their own demise, bringing about the end of the ice age with their filthy emissions. All the ATV parts were scavenged for modern art sculptures by the pack rats.
I think I worked it out, these must be the ghosts of the previous Joshua trees, when it was much warmer in the Minoan warming, the Holocene Climatic Optimum and Medieval Warming they all died.
The ones we see today are not real, they are just ghosts….
Matthew Bergin says:
“I always find it puzzling that a 0.7 degree temperature change that humans wouldn’t notice is supposed to kill all other life on this planet. The Joshua tree survives an 80 to 100 degree temperature shift from night to day on most days but don’t add an extra 0.7 degrees or its game over.”
What about the “tipping point” at 100.7 degrees?
/sarc off
And Joshua trees don’t look very yummy to me. The sloths probably all died of hunger. They should have eaten the pack rats instead; I hear they taste like chicken.
Lessee:
1. The Joshua trees,which apparently can’t survive a 1 or 2 degree F temperature increase, survived the greater warming 12,000 years ago.
2. The trees, which can’t survive without seed dispersal by large mammals like the giant sloth, somehow survived 13,000 years with nothing but little rodents, even before the great warming.
3. The trees, which apparently can’t survive the aforementioned 1-2 degree increase, somehow survive daily temperature changes of multiples of tens of degrees.
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.
[/sarc]
And if those rodents can’t move any faster than 6 feet per year, I can solve the problem right now: I have an abundance of squirrels and chipmunks here that move like fuzzy lightning, which I’ll be pleased to donate for relocation to the Mojave.
This continuous drivel about the desert is monotonous. Has anyone noticed the contiguous United States hasn’t warmed in the last 15 years?
Annual 1996 – 2010 Trend = -0.01 degF / Decade
Last 15 for the West Region(includes the Mojave), Annual 1996 – 2010 Trend = -0.26 degF / Decade
Last 15 for the SW(includes Arizona and N.M.) Annual 1996 – 2010 Trend = -0.31 degF / Decade
http://www.ncdc.noaa.gov/oa/climate/research/cag3/regional.html
Yes, very scary, I think the Joshua trees have cooling to worry about, not warming. Can’t these imbeciles do a study based on reality rather than a model?
I’d think the below zero weather last month across much of Josh Tree’s habitat ( http://wattsupwiththat.com/2011/03/01/a-cold-day-in-mexico%e2%80%99s-icebox/ ) would have more effect on the survival of many of these plants. Perhaps they should do a survey of how many Joshuas died from the all-time record extreme unprecedented really cold weather to see what the effect of actually occurring cold is compared to predicted maybe-will-happen warmth.
Its Friday, the brain is burning out, so I can contribute nothing but a humorous observation – stitching together some descriptive gems from two WUWT commenters today. (one piece from Latitude in this post above – the other somewhere else today)
New description for AGW alarmists….”Carbophobes suffering from irritable climate syndrome.”
Not only have these desert plants, as species, survived just fine, *individuals* have lasted for almost 12,000 years:
http://en.wikipedia.org/wiki/King_Clone
Facepalm.
“fossil sloth dung”
It’s just not for breakfast anymore!
I’m getting more than a bit fed up with people using unreliable climate models to make predictions of things 100 years from now and calling it science.
What killed the sloths? Can anyone name a species killed by climate change?
U.S. Geological Survey ecologist, when was this position invented? and why? would it have anything to do with government funding to promote AGW?
“climate change to be killing the Joshua trees”
So!?
Its quite simple really. Just tell the Joshua Trees to take the I40 NorthWest or the I15 East or 395 North and they’ll get around much easier and at a much faster rate than 6 feet a year!
So how about some real tests on the Yucca’s. Grow some in a suitable system where you can control the temperatures. Jack up the temperatures to what the models predict and see how the Yucca’s adapt. How hard can that be?
Apparently it has also become so yesterday to study a CURRENT plant species suffering from CURRENT warming!
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.
“It incorporated not only state-of-the-art climate models…”
Let me guess: worse than we thought?
I thought that the biggest danger to trees like Joshua Trees or Bristlecone Pines are Climate Scientists themselves!
Yikes. So many claims of doomsday, so little time to squash them all.
Reading about sloth dung fossils gave me my Mojave mojo back. Can’t wait for organically impregnated “Save the Joshua Tree” T-shirts to come out. Dirt bikers will love them.
This article had me very nervous that my first rule of biology papers and global warming was wrong. My rule states: Anything that is soft and cuddly, warm and fuzzy, tasty and nutritious, or generally useful and beneficial; will be reported as doomed by AGW climate change. Conversely, anything stinky, noxious, disease bearing, toxic, ugly, creepy, invasive, poisonous, or thorny will do quite well.
From the picture, I thought I was looking at a thorny plant. But, no thorns, its just thin long leaves and the plant is quite useful and beneficial. My rule stands.
I have had 4 Joshua Trees growing here in New England for the last 40 years. The seeds came from a tree above the snow line in Tehachapi Pass and take 4′ of snow and sub-zero temps through high 90’s in the summer. They are one tough species.
disclaimer: No Grant Money was spent for this long-term study. 🙂