Guest Post by Willis Eschenbach
“Out of passions grow opinions; mental sloth lets these rigidify into convictions”
Friedrich Nietzsche, 1844-1900
Anthony discussed the press release about the paper Past and ongoing shifts in Joshua tree distribution support future modeled range contraction. I didn’t have a copy so I wrote to the lead author, Kenneth Cole, to request one. He responded immediately and sent me a copy. My thanks to him, that’s science at its best. Other than the ritual obeisance to the climate models, the paper tells an interesting story about Joshua trees and the extinct Shasta ground sloths.
The Joshua “tree” is a cactus not a tree, it’s one one of the famous Yucca tribe of cacti spiny spiky things that aren’t cacti according to folks who know better than I do. Calling it a tree is merely the other cactus’s Yucca’s polite way to try to make it feel better about its funny appearance and desolate condition. It grows where almost nobody else can grow, in a very restricted climate range in the American Southwest. Not too hot, not too cold, not too much rain or too little rain, just right.
The fruit of the Joshua tree is a seed pod that was a favorite food of the Shasta ground sloth. The sloth appears to have been the only major seed dispersal mechanism for the Joshua tree. Which is hardly surprising, since other than pack rats and ground sloths, there’ve never been many herbivores hanging out where the Joshua tree grows. It’s way dry in that corner of the US.
The black stars in Figure 2 (from their paper) show the current location of Joshua trees, in and around the Mojave Desert in the hot Southwest.
Figure 2. The authors used rainfall and temperature maps to determine where Joshua trees might possibly grow, with green showing the most favorable climates. Map shows the lower parts of California (left) and Nevada (upper middle), along with a section of western Arizona.ORIGINAL CAPTION: … (A) Suitable climate model for Joshua tree created with mid 20th century (AD 1930 1969) PRISM mean precipitation variables and extreme mean monthly temperature events.
Now, to start with their map is interesting. I mean, the Joshua trees are certainly not growing extensively in what is the best part of the their range according to the authors. Unfortunately, much of the area they say is best for Joshua trees is on Nellis Air Force Base, so there’s no information for large areas. On the other hand, some areas with orange or even red (low probability) have a number of Joshua trees. However, nature is never as neat as we’d like it to be, and they’ve done well to generally outline the range by climate variables. And if it becomes desirable to plant Joshua trees, we know where they’ll likely grow.
Fifteen thousand years ago, in the days of the now-extinct Shasta ground sloth, the geological evidence from pack rat middens and sloth dung shows that the Joshua tree was much more widespread. However, humans happened upon the North American scene around that time, and converted all of the ground sloths into ground slothburgers and barbecued them. Which was bad news for the Joshua trees (not to mention the sloths), because no one else had much taste for Joshua tree seeds. As a result, the range of the Joshua tree is much reduced from its former glory.
The authors also show that the current range of the Joshua trees is further north, and at a higher elevation, than in the times of the ground sloth. During the last ice age the range of the Joshua tree extended across other areas that are now too hot or otherwise unsuitable to support them. As it warmed at the end of the ice age, the Joshua trees retreated (and advanced) to their current locations.
The problem is that without the ground sloths, the Joshua tree’s only seed dispersal mechanism is pack rats. The authors estimated the rate of spread from packrats at two metres per year. This seemed low to me, but is explained in the paper. The missing parts of the puzzle were a) unlike sloths, the packrats only carry the seeds a maximum of about forty metres or so to their homes, and b) the trees take twenty years to reach maturity and produce seeds. Result … 2 metres per year rate of spread. Always more to learn.
So far, so good. And if they’d quit there, it would have been an interesting paper. But no, they had to bring in the climate models. Now, climate models are notoriously bad at predicting precipitation (rain and snowfall). So they figured they’d pick the best of the bunch, viz:
Future downscaled GCM projections
To assess potential future changes in Joshua tree’s suitable climate space we compared future projections from several GCM’s for the late 21st century (2070 2099; ~2X CO2). Five individual models and one ensemble of 48 runs of 22 models based upon the A1B carbon emission scenario were obtained from the Program for Climate Model Diagnosis and Intercomparison (PCMDI; AR4) archive (available online). The five individual models used were: Hadley Center for Climate predic tion (Hadgem1), Max Planck Institute for Meteor ology (Mpi_echam5), CSIRO Atmospheric Research (Csiro_mk3), National Center for Atmospheric Research (Ncar_ccsm3), and Centre National de Recherches Météorologiques (Cnrm_cm3). They were selected because they represent a wide range of future moisture availability conditions for southwestern North America (Seager et al. 2007), and they all were ranked within the top half (of 22 models tested) for their ability to hindcast 20th century precipitation seasonality within the southwestern U.S. deserts (Garfin et al. 2010). These models, especially the Hadgem1 and Mpi_echam5, outperformed most models in replicating the 1950 to 1999 AD geographic distribution of average seasonal precipitation (Garfin et al. 2010).
Then, once they had what they figured were the best five models giving a “wide range” of rainfall results, they ran them and tried to figure where the Joshua trees might live in the future. The models gave differing results, so the authors defined a threshold for suitability (18%). If three of the five models said a particular gridcell would be above the 18% suitablity threshold for Joshua trees, they called it an “area of agreement for future suitable climate (AAFSC)”.
Then they show what those 5 models (and the 22 model ensemble) said would be suitable areas for Joshua trees in the years 2070-2099. Which all sounds vaguely reasonable until we look at their results in Figure 3 …
Figure 3. Results for five models (B-F) and 22 model ensemble (G). Pink areas with thin black outline show current range of the Joshua trees. ORIGINAL CAPTION: … (B G) The Joshua tree future suitable climate model runs for late 21st century (AD 2070 2099 AD): (B) Hadgem1, (C) Mpi_echam5, (D) Csiro_mk3, (E) Ncar_ccsm3, (F) Cnrm_cm3, and (G) Ensemble (44 runs of 22 GCMs).
See, if those results were mine, I’d throw up my hands and say “Not ready for prime time”. Those models are all over the map. They said they picked the models to “represent a wide range of future moisture availability conditions”, but I wasn’t expecting that huge a range. One model is “everything’s fine”, another is “they’re all gonna die!” That’s so wide as to be useless, and these are among the best models.
I don’t see any way that an average of those, or an “AAFSC” of those (area of agreement for future suitable climate), has any meaning at all. One of the models shows a wide area of hundreds of thousands of hectares where the Joshua tree could live, and another shows no suitable area at all.
Finally, once again we have the problem I have called “Models all the way down“. While the model results are interesting, they’ve skipped a big step. I want to see a map, just like the maps above showing possible future distributions of Joshua trees. But I want one showing how well the individual models (and the 22 model ensemble) did at hindcasting the current distribution of the Joshua trees.
I mean seriously – before showing us the model forecasts for 2070-2099 Joshua tree distributions, shouldn’t they show us the model hindcasts for the 1970-1999 Joshua tree distributions? It wouldn’t rescue the paper, but at least it might give some reason to think the selected models might be better than throwing darts at a map of the Mojave region.
Because without that, it’s just models disagreeing and quarreling with each other, all the way down …
w.
“I don’t see any way that an average of those, or an “AAFSC” of those (area of agreement for future suitable climate), has any meaning at all. ”
I never understood how averaging the outputs of nonlinear models makes any sense at all. You basically combine them into a more complex nonlinear model, but there’s no way you can say you improved some kind of quality. Maybe it’s so every bug in every model gets a chance to ruin the output.
Next, watch out for well meaning humans relocating all Joshua trees in a sad effort to save them, resulting in an extermination instead.
Small point (big point to botanists) – Yucca are no more cacti than other spiny pokey things that break the skin that grow in the desert. They are in entirely different Orders with completely different flower parts – you might just as well conflate humans with aardvarks… Great posting nonetheless!
Sorry Willis, but the Joshua tree is not a cactus. The Yucca tribe are not cacti. They are monocotyledons in the family Agavaceae (order: Liliales). A cactus is a dicotyledon in the family Cactaceae. Both are angiosperms (i.e., flowering plants). Both cacti and Joshua trees are adapted to dry conditions, and have independently evolved succulent (i.e water-storing) tissues.
Otherwise, great post! Keep up the good work.
You’ve published that painting of my dog and me without permission either of the artist, Carl Buell, or the owner, yours truly. Please remove it.
Also – not that facts seem to matter much here – Joshua trees are not even moderately closely related to cacti, much less being cacti.
[Reply: My sincere apologies for the picture, which was linked from google’s cache. I’ve removed it at your request. ~db stealey, mod.]
I remember reading a similarly interesting article that the main seed dispersal mechanism for the Osage Orange was the Imperial Mammoth. Apparently it’s been downhill for the Osage Orange since the demise of the Mammoth.
Also, the dissapearance of so many large Pliestocene mammels from North America is an interesting study in itself.
Well no wonder. No giant ground sloths no Joshua tree planting going on.
I was surprised though at how few places there are without any Joshua Trees. That is a first for me; a detailed map of where stuff ain’t.
Would come in handy when looking for something I have lost to ust have a detailed map of all the places where it isn’t.
Are Joshua Trees really cacti; I don’t think so. If they are “Yuccas which I would buy inot, then they are like the cabbage trees that grow in New Zealand; and I would think they belong to the Lily family rather than the Cacti.
Never planty any kind of Yucca or Joshua tree, even withoutGiant Ground Sloth assistance, anywhere near your house, and in particular don’t plant one near your gas meter.
I once rented a house in San jose, that had a Yucca/ersatz Joshua Tree, groing around the gas meter; and I do mean around. The incoming gas main to the house went right up through the tree, and the tree as it grew was pulling the gas pipe up out of the ground,.or trying to snap the gas meter off the top of it.
In any cvase, it is hazardous work trying to cut a Joshua tree/Yucca Lily from aorund your gas meter with a chain saw. Hey it is hazardous work cutting a Yucca with a chain saw, without either giant ground sloths or gas meters. The saw will jam in the pulpy wood of the tree, and kick back on you when you least expect it.
And I do own a house where some earlier owner planted Yucca/Joshua Lilies right up against the house, so they are in the process of turning the house over, aided and abetted by a giant Arecaria Pine from Patagonia, a three foot diameter trunk tree, that is a8 inches away from the house wall, and has its own semicircular encroachment on the eave of the house. When the wind blows, you can hear the tree trunk, banging up against the house.
Hey this house is so old, that it could easily have been Giant ground Sloths that planted the Yucca lilies. Is the Sego Plant a lily related to the Yucca/Joshua Tree ?
But I don’t think they are a cactus.
Gotta love those Klimate models.
Nice picture of Chris Clarke, Zeke and the giant ground sloth, painted by Carl Buell. Might be nice to add a credit line beneath it.
Somehow that a8 inches was supposed to come out at 18 inches.
Because without that, it’s just models disagreeing and quarreling with each other, all the way down …
What say they as to the number of Angels on the head of a pin? Just thought I’d ask since the Turtles have been so slow in responding.
I think the model results of this paper are absolutely perfect.
Without a doubt, they show exactly what we should be deriving from computer models applied to climate forecasting and impacts on global systems.
Namely, nothing.
Excellent point, Wills.
No model forecasting the future should ever be allowed to be published in a scientific journal unless it clearly demonstrates ability to “predict” the past.
Else a model is merely a highly expensive and worse than useless guess. An opinion, a passion, disguised as the “truth” for the gullibles.
Regards
Sanjeev
Willis, thanks as always for writing a post that’s not only educational but fun to read.
Ahh, the Joshua tree. Brings back memories of this midwestern boy’s first foray into the Mojave back in the early 70’s. I had never seen desert trees before and didn’t realize that the green “leaves” were actually very hard spikes. I approached the tree to partake of the shade underneath, only to run face first into one of these daggers they call leaves. The face bleeds quite profusely when punctured by a Joshua leaf. My mother still laughs at the memory, though she was quite concerned at the time.
The environmentalists would probably shoot me today if we tried many the fun things we did with motorcycles in the Antelope Valley back then. I still remember going full throttle up one of the buttes out there, coming to an unexpected peak with the trail going down and to the left, but straight ahead, like the goal posts on a football field stood a Joshua tree with no middle branches just ones to the left and right. Doing about 70 at a 45 degree incline and no time to do anything about it (12 year olds are stupid!), I jumped right through the open arms and landed in a group of tumbleweeds and continued on as though nothing happened. (I did learn a bit of wisdom though and took new trails at a reasonable pace afterwards!)
It is too bad about the seed dispersal problem. It does tend to shine another light on the popular myth of the Native American connection to all things living. Hunting a prey animal to extinction sure isn’t a very green thing to do. (I am part Indian [very small part] and have always thought Indians are just people too with the same foibles and strengths as any other.)
#
#
Dave Stephens says:
March 30, 2011 at 3:05 pm
Small point (big point to botanists) – Yucca are no more cacti than other spiny pokey things that break the skin that grow in the desert. They are in entirely different Orders with completely different flower parts – you might just as well conflate humans with aardvarks… Great posting nonetheless!
###
Aardvarks are way closer to humans then cacti are to agavae!
So it is like I So:ed the last time.
Climate change has nothing to do anything with them little cacti trees.
Essentially, they’ve survived 50 000 years, the loss of 50% of their seed carriers, the rise and fall of a whole ice age, and tens of thousands of tripping freaking hippies thru the ages (as has another more famous but slower growing cacti.)
Of course they might not survive the crazed climate communist hippie vegan crowd trying to dissect every veggie looking carbon dioxide to oxygen filter they happen upon, to feel sorry for, before they frigging devour it. Still that has nothing to do with climate change, lest, of course, one start to ponder the local climate of hippie under pants?
George E. Smith
March 30, 2011 at 3:33 pm
The sego palm is not even close to palms or any flowering plant for that matter! They represent true ancients. Google them, you will be facinated ( I hope).
Have just had the misfortune to visit Mr Chris Clarkes site (out of curiosity due to his complaint) and noted his out of hand dismissal of this site! Not good form in my humble opinion – but I guess us denialists are used to it!
But I would like to make a couple of observations (mods and Anthony permitting?)
Firstly, if a picture from google is ‘out there’ – shouldn’t his complaint be at least partly directed to them.
Secondly, wherever the image was found, was it properly credited/attributed and copyright claimed?
Thirdly, I am curious as to the reason for Mr Clarkes visit to this site – obviously a warmist, I can only presume he was ‘tipped off’?
And finally, with the deepest of respect – I can honestly say that the majority of folk I have read on this site are decent people – mostly in the quest for an honest science appraisal instead of politicized Bulldust. Of all the sites where an honest mistake can or could be made – this is the most likely – and I suggest that Mr Clarke would find it well worth reading.
The path to enlightenment is a long one, dear brother…….
Chris Clarke says:
March 30, 2011 at 3:14 pm
Done, with my apologies. Sorry I linked to your site, I was hoping to drive some traffic your way to benefit both you and your artist, but since you obviously don’t want that, it’s gone. Enjoy the silence. You could also mention to your artist that you prevented his work from getting wide public exposure on a non-profit site with a link to his original work. I’d prefer you tell him and not me, for the obvious reason.
I’m happy to remove the painting, and in fact one of the moderators beat me to it while I was writing this. That’s how we do it here. However, if you want to add childish insults, well, that loses you points rather than gaining them. It just makes you look petty despite the fact that you are right. And you were doing so well, too. In the future you might consider quitting while you’re ahead.
I have changed the cactus reference to avoid insulting the Joshua trees by thinking the cactus were related to them, perhaps you could apologize to them for me as well. You do understand that my whole riff on cactus was just humor, and had no real bearing on the paper?
w.
I have a picture of me and a dog that you’re welcome to use. Maybe Josh could whip up a sloth and a joshua tree, you could strip them all together for a nice replacement.
I’m sorry that Chris is upset about his likeness being used. I clicked on the source and saw it on that URL….and since he’s upset about people seeing it, I promise I won’t go there again or look at him.
To the point…species come, and species go. When they live in environments that are “perfect” to their evolution (egads! he used that word!), they’re living on the edge in the first place. How many other myriad species have come and gone because the climate that developed and they adapted to changed, and they didn’t un-adapt?
How do we know that these plants won’t simply adapt quite nicely?
As for hindcasting? You’re going to suggest using that to validate a model?? Heresy.
Hank Fox says:
March 30, 2011 at 3:35 pm
Before the picture was removed at Chris’s request, the picture had what’s called a “link” to Chris’s site which contained all of that and other information. If you pressed that little blue thingy with the line under it (the “link”) it would have taken you to Chris’s web site.
This was much better than a credit line, because it took you where you could actually find out about Chris and his dog and the Artist Currently Known as “Removed at Chris’s Request”.
All gone now.
w.
Well said and agreed Willis – one day, when I have accrued enough cash for a flight, I would like to fly across the Atlantic just to meet up and share some stories and experiences!
Good post anyways!
Most importantly, when will the Climate Modellers finally confront the ultimate question, “Who is going to feed the bed-bugs?”
Good article Willis as usual but I don’t believe any of their “studies” and I find it hard to believe any study about 13000 year old crap. I think maybe you don’t either but I guess I could be wrong . I think the study is sloth crap.
I wonder if they know that Y. brevifolia is commonly sold in landscape nurseries, and hort maps say it’s hardy zones 5-9….
It’s even sold in Florida retail nurseries…
…someone needs to tell them that it’s too delicate and needs very specific conditions and it won’t grow there /sarc
Willis Eschenbach says:
March 30, 2011 at 4:08 pm
Very nice read as usual Willis. A perfect example of models and ensembles at “work”! I always look forward to you posts.
On the topic of the image, It is not clear who owns the copyright on that image, the author or the subject, yes subject, not owner. You only own it if you own a hard copy. Copyright usually is the author’s unless a written or “implied” contract exists. I am a photographer so I routinely deal with copyright matters.
Also, the image in the subject’s site is the same as in the author’s, so it is entirely possible that the subject got it from there to begin with. I visited both the subject’s and the author’s website and neither claim a copyright.
You and the mods did the right thing as always of course, but not before we got a chance to see the the subject’s true colors. That made it all worth it for me :).
Thanks again!
Best,
Jose
Great opportunity for some keen green Johnny Joshuaseeds to get involved. Let them eat these seeds and dump in desired areas. Be a surrogate sloth to save the planet! Could catch on, especially for vegans who already appreciate a hearty sloth diet. It is possible that the sloth’s extensive digestive system prepared these seeds for germination but it seems worth a try, for the entertainment at least.
Of course, it is possible that the current catastrophic climate disruption will have unprecedented impacts on delicate feces ecology and that could doom this noble experiment.
So, perhaps it would just be simpler to get a Pied Piper to lead the packrats on longer journeys… or maybe not do anything at all.
I wonder if they consider humans like packrats. I mean if you google “Joshua Tree seeds” there are many reputable vendors, and some unreputable. So humans are spreading them now, internationally. Granted Joshua tree is very site specific and will not thrive where the vendors send most of their seeds to. But they are growing in Albuquerque via humans, and their future there is very questionable and remaining to be seen after the extreme cold temps in ABQ this winter, and if I recall I think it was pretty cold last winter too. The Needle Palm (or world’s most cold hardy palm) also had a sloth and a greater range in historical times, and is thought to be moved by glaciers to its current range which is Louisiana to South Carolina, and its pretty rare. But humans have spread it up past NY into New England, west to Colorado and British Columbia and into South America and to Europe and of course anywhere in the world where anyone would want one (back to the international seed vendors). And a warming climate would benefit them, as would wetter conditions since they are found near rivers and moisture for the most part. Global warming would increase their range I would think. But regardless of the AGW slant or not, the way plants range historically is a fascinating topic! And this was a very interesting post. I’m not sure that the average of the models is 100% useless, but I’m not sure the conclusions are accurate just because nature is so complicated.
Good thing we are combating climate change in the hopes of expand the Joshua tree’s range by puttin up vast arrays of solar panels in the Mojave…which will eliminate thousands of acres of the Joshua tree’s range.
*chases tail
@Willis Eschenbach
If the population of Joshua Trees are in decline you could always use that “trick” of yours we discussed the other day, to round up the figures , that should add a fue million trees. /JK
Interesting article as always.
Regards~
Good grief, Chris Clarke is quite the character.
Poked my head in at his blog and I won’t be going back there again. The folks are RC have better manners than him.
Re: latitude
“it’s too delicate and needs very specific conditions and it won’t grow there”
Your is very accurate. Check the nursery’s warranty on them lol Because they are sold does not mean they will thrive. But they may in fact thrive, anyone in a place like Florida with high atmospheric moisture would have to site accordingly in dry well drained soil or a raised bed. Then it would need to survive “long term” which is thought to be 20-40 years or so, facing the “30 year winter” or rain storms or whatever the climate and cultural differences in the sites. Culture does not mean human culture btw. But to say zone 5-9 is a real stretch. USDA temperature zones are designations for the one coldest night of the year averaged in a dataset (of years) so only one coldest night (one coldest temperature of the winter, only 1) of the year, averaged over a defined time period. Zone 5 can stretch from Maine to Ohio to Texas, Colorado, Idaho wherever without regard to precipitation, soil types, sun angle etc… so its not “hardy” to all of zone 5, but can survive zone 5 temperatures under very proper conditions for it which is very dry and very warm. Although it does experience fog and moisture in habitat, and this may help its adaptability in other places. But it is not thriving and widespread and most people fail at cultivating it successfully for short or mid term let alone long term outside of a very similar and suitable climate. USDA Zone 5 btw would mean on average it would see lows between -10 and -20 F
The USDA map changes periodically there have been several and what dataset of years they use becomes controversial at times not too unlike AGW, if you choose different years the map can move north or south. I think they are working on a new one right now that will be computer interactive with more variables included but I’m not sure.
Hindcasting… hmmm…
that’s all very well so long as you don’t alter past data to match what your model tells you happened…
but of course nobody would ever do that, would they. 😉
Kev-in-Uk says:
March 30, 2011 at 3:59 pm
No, it was properly directed here, the action was mine, and we were the ones who could (and did) respond immediately to his request.
Dunno …
Please, speculations about peoples motives are abhorrent. The most likely explanation is that he has a google alert set to the name of his blog, or he watches where the referrals to his blog are coming from. In any case, speculation is unwarranted and unwanted. I assume that Mr. Clarkes is acting in good faith until I see incontrovertible evidence otherwise. And to date I’ve seen no evidence of any kind, much less “incontroverible” evidence, that he was acting in bad faith.
Generally, I feel comfortable using anyone’s image as long as I cite it and link to it. This blog gets a lot of traffic. If I can drive some of that traffic to the website where the image originated, I think most people won’t have a problem with that.
For those that object, of course, as in this case, we remove the image immediately. I don’t fault Mr. Clarkes for making the request. I didn’t like the tone of his communication, and I objected to his accusations regarding the general factiness of this site, but he has every right to object to the use of the image.
w.
The hyperlink provided above, by the testy Chris Clarke, links to his blog.
On that blog he lists a a resume. On that resume there is a category labeled “Activism”.
It all makes sense now.
grzejnik says:
March 30, 2011 at 4:59 pm
=============================
Re: grzejnik
The only reason they are not used more in landscaping is because they are so butt ugly….and nasty
AdderW says: “Next, watch out for well meaning humans relocating all Joshua trees in a sad effort to save them, resulting in an extermination instead.”
No, the Green philosophy calls for relocating the humans to save the trees, and extermination of the former is an acceptable alternative. (See the 10-10 video.)
Chris Clarke says:
March 30, 2011 at 3:14 pm
You’ve published that painting of my dog and me without permission either of the artist, Carl Buell, or the owner, yours truly. Please remove it.
Also – not that facts seem to matter much here – Joshua trees are not even moderately closely related to cacti, much less being cacti.
==============================================
lol, panties get in a wad often? Did you bother reading through the article? Other than the official classification of the non-trees, do you have any factual refutation of what was stated?
While these frequent drive-byes are often a source of humor for the many of us, I can’t help but be incredulous about the statements. “Fact’s don’t matter”. Ok, fine. Show people where they’re wrong. If you can’t, then it is simply a matter of projection. More, not only are you showing the world the alarmists intolerance of intellectual discourse, you’re showing the world the alarmists lack of capacitance for intellectual discourse. Don’t get me wrong, I enjoy witnessing the vapid vacancy, and I take comfort in the fact that for every commenter here, there many more readers. But every once in a while, it would be nice if the alarmists could display just a little cerebral capacity. It shakes my belief in my fellow man.
James
Reminds me of the El Nino models. Future forecasts say: Half say neutral to El Nino is on the way, half say neutral to La Nina is on the way. The average of all the model forecasts is highlighted. Huh????
Who is Chris Clark and why do we care what he thinks?
How long do the seeds stay viable ?
I.E. are dormant seeds lying all over waiting for the the right “climate”?
These maps include much of the Imperial Valley that has gone through a man-made water shortage in recent years.
Willis
Thanks for getting past the press release. After finding the study completely hidden behind a pay wall which is currently not even available in major universities (I tried CalPoly Pomona, UCLA, University of Arizona….), I was able to track down the taxpayer funded project which apparently paid for much, if not all of this work. It makes interesting reading:
http://sbsc.wr.usgs.gov/research/projects/sbsc.aspx
Also: http://biology.usgs.gov/ecosystems/global_change/packrat_middens.html
I remain convinced researchers would do well to pay more attention to recent changes before reaching firm conclusions about remote times. Example, which I commented on in the earlier post on Joshua Trees: Lake Cahuilla. Today’s Salton Sea has a surface area of about acres and evaporates an estimated 1.3 million acre feet a year. The top of the water is slightly over 200 feet below sea level. By contrast, Lake Cahuilla at maximum filling had an area of more than 2000 sq miles and a surface elevation well above sea level. It was six times as large as the Salton Sea and I find it hard to believe that it did not have significant effects on the surrounding climate.
The surroundings, of course, include the immediately adjacent Joshua Tree National Park:
http://books.google.com/books?id=a73tq1dXqYcC&pg=PA16&lpg=PA16&dq=salton+sink+prevailing+winds&source=bl&ots=V6N4YPOjc8&sig=n7R7bsyyWAADpRBs4h2w0Bzezg8&hl=en&ei=B2SRTdXKBYH6swO5m_y0Dg&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBUQ6AEwAA#v=onepage&q=salton sink prevailing winds&f=false
(See p. 19)
We are gradually accumulating a well-dated record of recent high fillings, as late as the 1700s:
http://www.physorg.com/news/2011-02-lake-effect-theory-quake.html
The study area is in the dry bed of prehistoric Lake Cahuilla at Coachella, Calif. The lake has been dry since about 1715, according to timelines found in early travelers’ descriptions of the area. Researchers found that the lakebed was full of water six times in the study period.
“We now have the best chronology of these lakes that has ever existed,” said Weldon, who knows the area well from previous work.
This suggests the possibility of correlating these fillings with possible climate proxies in the region, including Joshua Tree distribution. (To be sure, the coming and going of Lake Cahuilla was so frequent and on such a short timescale, that any distribution proxy is highly improbable.) There is even the possibility of detecting the effects of the sudden formation of the Salton Sea in 1905, in the instrumental records of the COOP weatherstations of the area, though such effects would be much smaller than a high-level filling.
Willis Eschenbach says:
March 30, 2011 at 4:08 pm
As to the boy & dog picture—I’m sure it’s a good one or Richard would not pick it—but I say “good riddance to bad rubbish” about Chris’s attitude. There are plenty of great free & open pictures on the web. If Chris wants to play in this webspace, he better get ready to be a webspace player. If he doesn’t, well I hope the screen door doesn’t hit his a*s too hard on his way out. Well, maybe hard enough to leave an indelible weave pattern.
Okay, I’ve read the thread and the post. I have no idea what these seeds look like–color, diameter, shape, toxicity, density. How big are the pods? I’m curious. Perhaps Ken Cole could persuaded to provide a brief post giving a little more information. For instance, do birds eat the pods? I’m sure there are a number of interesting facts that he could provide that would clarify the thinking behind the article and put the final maps in perspective.
My first link (above) won’t quite get you there. From the linked page, click on Colorado Plateau Research Station, then on “Modelling Future Vegetation Change.”
OK, Salton Sea surface area should read 378 sq. miles.
Re the new Ground Sloth pic. It looks like she’s eating oak leaves. Any creature that ranges from oak forests to Joshua Tree deserts must be as well adapted as good old Homo Sapiens.
And the long link works if you replace the space between salton and sink with an underline.
Murphy was indeed an optimist.
Note to readers:
The new photo is of an Iowa sloth, now extinct because they ate all the Joshua Trees in Iowa years ago.
There are probably folks in California who could replace the sloths.
But activism is so much easier because afterward you can go home where there is a warm fire, soft lighting, wine, etc.
If I place my head in the oven and my feet in the refrigerator, on average I will feel pretty comfortable.
It appears that, if you use enough models, the spread of ranges for almost anything will cover whatever it is you wish to promote.
Many here might already know the story of the discovery of the long thought extinct Wollemi Pine here in the Blue Mountains in eastern Australia.
There are less than 100 trees of this 200 million year old species now known to exist, all in the one tiny very isolated rugged mountain area.
But the most remarkable thing is that it was thought that this species, based on the dating of the last known fossils of the genus, had been extinct for some 2 million years.
Yet those trees survived down through the ages in this one small isolated pocket until accidently found by David Cole, a bush walker and a rock climber and fortuitously also a Parks Field officer who recognised that there was something very unusual about that isolated group of trees in the deep gully.
The conservation effort for this species is innovative in itself as rather than locking down the trees, the locations of which are still a closely guarded secret, into a entirely preservation only role, the decision was made to propogate and distribute the trees across as wide a region as possible and ultimately to be distributed nationally and internationally so as to ensure the survival of the species across a vast range of climates and environments.
I try to avoid ad hominems, but this fellow is obviously a complete . . . jerk, and a fool besides.
We don’t care what he thinks. But it is instructive to read his nasty insults just to get a feel for how utterly close-minded the ‘activist’ ideologues really are, and then compare it with the energetic, sometimes opinionated, but generally fair-minded discussion that takes place daily on this blog.
/Mr Lynn
Willis
Good observation: “climate models are notoriously bad at predicting precipitation (rain and snowfall).” Excellent challenge: “I want one showing how well the individual models (and the 22 model ensemble) did at hindcasting the current distribution of the Joshua trees.”
David Stockwell exposed how models used by CSIRO’s Drought Exceptional Circumstances Report on hindcasting gave the OPPOSITE of historical data:
Stockwell, David R.B., 2010. Critique of Drought Models in the Australian Drought Exceptional Circumstances Report (DECR), Energy & Environment, 21:5, 425-436, DOI:10.1260/0958-305X.21.5.425, Link: http://multi-science.metapress.com/content/L4870G0N8Q064377
I had the pleasure of visited Joshua Tree National Park last August. It was warm and dry. Here are a couple of quotes from placards inside the park.
“In the late 1800s and the early 1900s, cattle ranching was an important business here. An average of 10 inches of annual rain fell upon the desert then (compared to 2-5 inches now), and grass ranges were lush and abundant in Lost Horse, Queen, and Pleasant valleys. ”
What is now the park was then part of at least two cattle ranches.
Referring to the Joshua Tree: “Beechy ground squirrels, birds, and deer eat the creamy white blossoms, later fruits and seeds provide food for antelope, ground squirrels and other small animals.”
Hmmmm. The climate changed and multiple critters now seem to participate in eating (and potentially spreading?) joshua tree seeds.
juanslayton says:
“The top of the water is slightly over 200 feet below sea level.”
I wonder how much energy would be generated if a pipe were run from the ocean to the lake, with a Pelton water wheel hooked to a generator?
The lake is already brackish, so sea water wouldn’t make much of a difference.
It would be pretty cheap electricity.
The Joshua Tree. U bloody 2. Bono is up there with the rest of the warmistas, the warmerazzi….
jorgekafkazar says:
“Okay, I’ve read the thread and the post. I have no idea what these seeds look like–color, diameter, shape, toxicity, density. How big are the pods? I’m curious.”
A search for images found this.
Apparently 22 climate models run 44 times created an ensemble that forcast, in aggregate, it will be either; hotter and wetter, hotter and dryer, colder and wetter, or colder and dryer than Joshua Trees can tolerate before the end of the century.
I applaud the decision of the sloths. Pre-emptive extinction has the advantage of self determination with regard to the timing of a species passing into the dusty tomes of the paleoclimatologists. Humans however must remain at the mercy of the models for survival and rely on the paleopackrats to accumulate and analyze the artifacts of humanities endevors or something.
Ken Cole has been studying the Joshua Tree for quite some time. I have located a poster from 2005 in which he made projections of present and future distribution of Joshua trees using the climate models he had available at that time. Since it is a poster, a lot of the details in a full paper are missing.
http://www.climatescience.gov/workshop2005/posters/P-EC4.2_Cole.pdf
One thing he did in the poster, that is lacking in the paper as you describe it, is a prediction of the current range of the Joshua Tree, from the climate model that he used for prediction of the future. It is found in figure 5. He doesn’t compare it directly with the data on the current range. From what I can see on the map, the current climate seems to predict the observed range in Joshua Tree National Monument in the Little San Bernadino Mts.
Willis,
Do you think the paper was publishable is the peer review literature without the model speculation?
What are papers doing publishing conclusions based upon the AR4 models or their successors without a discussion of the diagnostic literature? The diagnostic literature at the time of the FAR already documented both significant correlated and uncorrelated error, and much has been published since then in plenty of time to make it clear to these authors that the models have no regional or quantitative credibility for the purpose they put them too. The IPCC itself published projections bounded only by the range of model results and emissions scenerios making absolutely no attempt to account for the additional uncertainty from problems already documented. The ranges of the projections gave the deceptive impression that uncertainty was disclosed and it wasn’t. This is key reform that needs to be made in both the IPCC process and the quality of peer review in climate science and other research like this one which uses climate science product. Each model team has an obligation to maintain a repository of diagnostic results for their models and new versions of their models that have not explicitly addressed past diagnostic issues. Announcements of new model versions in the peer review literature should not be little more than press releases touting features, but should specifically address past diagnostic issues addressed and unaddressed. The Wentz paper in Science showing that none of the models produced even one half of the observed increase in precipitation, should give any authors addressing droughts and the extent of arid conditions pause.
As a matter of routine, I hereby confess that I am an old retired bureaucrat in a field only remotely related to climate, with minimal qualifications and only half a mind.
Willis,
Would it not be appropriate for you, as a climate scientist, to write to the authors and ask them, in the interests of science, to run your hindcasting and let you know the results. You might like to add that if the results were embarrassing, they could do so discretely.
Willis, not throwing darts.
They are throwing chicken bones.
How sad
This is going to sound a bit nuts, but in the Rogue River Canyon upstream about oh 10-15 miles nearer the dry than the wet part of the canyon. in this guy’s yard is-a
Joshua tree.. I though it a palm of some sort until I was based at Fox Field in
Lancaster Ca. There are Joshua’s around there for sure. That was a Joshua
in that guys’ yard.. Don’t know if it is still there. Wife who’d been married to a
Desert Rat of sorts(emphasis on Rat) in her first marriage spent some time around Mojave.
She said it was a Joshua. I said that’s impossible! Well, maybe not…
One of the things I learned about Joshua trees while racing motorcycles between them is that they send out runners from which sprout more Joshua trees. These are impossible to transplant with any degree of success, but people try all the time and the result is a dead Joshua tree start and a wounded runner.
This is not common knowledge, but standing around the fire pit late at night passing the jug around, nothing burns hotter longer than a Joshua tree. The desert sky is generally running at around -50º or so, so the fire is really welcome. And explains why so many Joshua trees seem to be pruned at just about shoulder level. It also ensures you don’t get hit in the face by the spines when riding off into the night on a dirt bike to answer nature’s call. I can easily imagine roasting a slothburger over a Josh fire and keeping it hot with pucker bush limbs. It even works for cowburgers.
The pucker bushes out there burn like gasoline but are out quickly. And bonus – the Joshua trees provide their own skewers for the hotdogs. Wood taken from pucker bushes (also called creosote) looks and smells like cedar and makes fantastic pistol grips and all manner of things turned out from wood craft shops. The grain is so fine it seems not to exist.
The greater threat for them though, is urbanization and a desert wide water grab. You want putting greens or Joshua trees? Can’t have both. If you have time, learn about the Mojave river. Mostly underground, it has a remarkable flow rate. Careful where you pitch your tent!
It will take years (probably 5 or more) to kill AGW. I have come to the conclusion as many others have that too much money/jobs etc, has been invested in it. It will be a slow process.. by the time the polls show that 10% or less believe in it, it will then die. And skeptics, you will not get your pleasure to see this, because it will be “old soldiers fade away, they do not die” phenomena. In other words the warmist will not concede, they will simply disappear over time, probably 5 years as stated above. It is a process that fortunately has already started. For example, hits to real climate etc in massive decline since 2007 and so on.
“However, humans happened upon the North American scene around that time, and converted all of the ground sloths into ground slothburgers and barbecued them.”
Lol…you have a way with words there Willis…
Great thread.. very enjoyable and informative read.
But..
Smokey says:
A search for images found this.
WOAH! Waaay tooo U-G-L-Y!!
Would anyone really care if they died out?
Hang on a minute,Physics Major says: March 30, 2011 at 6:08 pm
How did you figure the sloth was (is) a female?
Willis thank you for the update on the article.
However can you direct me to a more detailed map than provided Fig 2 of the area? I can not place the maps provided in this blog within the US s-west + coast area.
Is this map near the research area?
http://www.sdge.com/sunrisepowerlink/maps.html
(note various parties of interest in http://www.sdge.com/sunrisepowerlink/docs/srpl_whitepaper.pdf )
or this of the Lake Mead National Park area with the bighorn sheep petroglyphs http://www.nps.gov/lake/planyourvisit/maps.htm ?
I note there is a Mojave and Colorado Desert biosphere reserve (UNESCO 1984) with four management units, one of which is the Joshua Tree National Park (source http://en.wikipedia.org/wiki/Mojave_and_Colorado_Deserts_Biosphere_Reserve )
I have never viewed so many national parks and crossing state borders. Amazing.
And radiometry (not carbon?) controversy of Nothrotheriops shastensis bones and dung and Harrington
http://www.1st100.com/part1/harrington.html
I would beware of sloths gone mental, too.
I would have to wonder where the heck those things lived because in the areas where I see the most Johsua trees, I wouldn’t think anything that large could survive out in the open during the day and there certainly isn’t a lot of shade to be had.
Yet another great post, Willis, despite a botanical faux pas and noises off from some testy nutter.
I won’t bother to suggest yet again that an anthology of your pieces would be something to treasure…….
If I might offer a small OT comment, I visited Joshua Tree National Park (and stayed in Twentynine Palms – and, no, I’m not a hippy!) a few years ago. I thought the National Park (and all the other US National Parks I have managed to visit) was absolutely wonderful. Even nasty denier types can appreciate nature and scenery.
Just thought I’d like to give the park a little plug on here.
How many silver nails do you have to hammer into the heart of the Greater Fanged Vampire climate model before you kill it, Willis?
Another great post apart from the minor faux pas about genus, but mistakes such as that certainly flush new knowledge out into the open. The silliness from Chris Clark was something of an eye-opener, so I visited his website out of curiosity and was amazed by the gratuitous nastiness toward sceptics of CAGW and to WUWT, the utterly closed state of his mind, his fiercely uncompromising warmist stance and his awe of RC as a ‘resource for real science’ (wow!), but then another poster kindly provided his bio and everything clicked into place for me.
Was it the Clovis culture that is accused of making too many slothburgers, and wiping out the sloths? Apparently they hired a lawyer, and now are better defended.
I grew up reading the Clovis culture wiped out all the big game in North America, much like cowboys did to the buffalo with repeating rifles. After they wiped out their food source, they supposedly died out, for, rather than repeating rifles they had big spears, and the spear points disappear along with the big game.
However I think the timing of the extinctions caused problems. Someone figured out all the big game vanished at the same time, as did the Clovis culture. This would have required the Clovis culture to go coast to coast on interstates, whipping spears about like crazy.
The Clovis culture lawyers came up with a new idea: A comet smashed into North America, causing a return of the ice age world wide, and hurting North America worst. Not only did all the big game die off, but so did the Clovis culture.
Therefore the Clovis culture lawyers request that you remove the insinuation they are responsible for the extinction of ground sloths. Heck, can’t fellows even have a burger in peace?
I posted a rather intemperate reply to the intolerant bigot Mr Clarke. He deleted it. Fair enough. However another poster supplied some links to a lecture which was very interesting. My response was below. I suspect it will also be censored.
I see you have deleted posts which included a well respected and knowledgeable physicist debating global warming.
I should also say that I do not debate scientologists having a brother who is one or homeopathy but I do have the intellectual rigour to discuss the problems of AGW. And there are many.
In the interests of diversity I’ll repost them so your readers can hear another view. Nothing like diversity
Check out http://www.youtube.com/watch?v=8BQpciw8suk for environmentalists with short attention spans or if you wish to see the whole thing http://www.youtube.com/watch?v=VbR0EPWgkEI&feature=related
Although I agree with the decision to remove “The picture” when asked.
Wouldn’t its continued use be allowed under the Fair Use Doctrine? Especially as the location it was linked from doesn’t claim a copyright or prohibit its use.
Mr Lynn says:
March 30, 2011 at 6:30 pm
Jack Linard says:
March 30, 2011 at 5:46 pm
Who is Chris Clark and why do we care what he thinks?
I try to avoid ad hominems, but this fellow is obviously a complete . . . jerk, and a fool besides.
We don’t care what he thinks. But it is instructive to read his nasty insults just to get a feel for how utterly close-minded the ‘activist’ ideologues really are, and then compare it with the energetic, sometimes opinionated, but generally fair-minded discussion that takes place daily on this blog.
/Mr Lynn
———
I think you forgot to put the /sarc at the end of that sentence…
Can we assume that the shasta sloth ‘seed distribution mechanism’ was similar to that employed by the Asian Palm Civet for Kopi Luwak coffee?
http://en.wikipedia.org/wiki/Kopi_Luwak
A study assessing the utility of biomarker approach to coprolite analysis – and using a
1gm sample from N shastenisis was conducted in 2009.
The dung sample was taken from Gypsum Cave, Nevada, where Harrington (1930)
published ground sloth habitation dated 8500-6500BC and human habitation is dated 3000BC (source wiki)
Table 2 of the article lists the dietary plant saponins specifically epismilagenin
inc Yucca sp which was not published or at the least researched until 1990s
http://www.chm.bris.ac.uk/~chidb/personal/content/paper33.pdf
And why is the question of Pleistocene birds and the collection of seeds (or dung) in nesting/mating habits not discussed? Or are these birds, such as for eg
the bowerbirds of Australia/PNG peculiar to isolated geographical areas or
a later period?
How about someone makes this their hobby – just as sequoias have people who care about them – starts growing them by the hundreds in flower pots and then goes out planting them in the wild in their spare time?
I have a computer model that proves it.
Wow, been around them for years and did not realize that the “Yucca Palm” was really a Joshua Tree. They are all over Florida and even up to the Salt Tolerance zone 2 on the barrier islands. I guess I have seen them as close as 100 yds to the ocean. Not a fragile plant at all.
I remember them most for what the one in our front yard did to a football every year (the oblong spheroid type, not the round ones). We had to patch a football every year because it landed in the yucca. The points could be used for anything you use a pin for. And we would stick them into themselves. The ‘plastic’ skin has that same ‘taste texture’ as a green persimmon, but much less so too.
Oh… I forgot until minutes later. The local name in Central Florida in the 70’s was a Spanish Bayonet. Another reason why the latin nomenclature is always the best way to describe them. But those change too (cichlids are all messed up from when I learned them).
As W. C. Fields would likely say, “Sure I like sloths; fried, baked or boiled; before or after my drink!”
Physics Major says: March 31, 2011 at 7:41 am
Super stuff, post it up please. I’ve always wanted to learn a visual technique based on the study of matter and motion for spotting the correct gender in ambiguous situations.
“Spanish Bayonet” is a different species of yucca.
There are lots and lots of yuccas.
Most–possibly all–depend on the yucca moth for pollination.
The moth comes around and does its thing, laying eggs in the pistil of the plants and picking up pollen to carry around. The growing baby moths, AKA caterpillars, eat fruit pulp, possibly some of the seeds, and later on the fruits are ripe and big moths hatch out…details here I am fuzzy on…
You don’t want to lean on Spanish Bayonet while pulling weeds. It has poor resistance to lateral forces. One of ours fell on my hubby’s head when he leaned on it while yanking out the Johnson grass that had sprouted around its base.
I suspect that both of these things, the moth necessity and the breakage, apply as well to the Joshua tree. Maybe one reason it’s not as widely spread is a decrease in the applicable variety of yucca moths? I’m not at all convinced that these plants are spun glass already.
Best to all
KL
George says:
March 31, 2011 at 7:53 am
Another reason why the latin nomenclature is always the best way to describe them. But those change too (cichlids are all messed up from when I learned them).
####
At least Aequidens and Apistogramma have remained fairly stable, Cichlasoma not so much. For a while, I was finding that I needed to review the literature every few weeks just to keep abreast well enough to support my customers.
Mental sloth and Joshua Trees…..didn`t they both release punk albums in `76?
Visiting a lithium project in northern Nevada last December, I saw some clumps of joshua trees southwest of Tonopah (el 6000′) well north of the maps shown for their range in this article. I didn’t know they were joshuas until I saw a picture of them on WUWT. It seems to me that if you are an expert and want to be seen as such, you should have a better knowledge of their range than an Ontario, Canada rare metals consulting geologist.
I’ve seen this sort of thing before. Fifty years ago, mapping geology for the Manitoba Geological Survey, I had read an article on N.America’s foremost specialist on bald eagles in which he gave their habitat extent as extending into Canada only in a narrow zone along the Rocky Mts. I wrote to him and advised that they occurred virtually across northern Canada and invited him to visit a number of places where he could study them (I later also saw them in Yukon Territory). He wrote back that it was common to mistake them for some other bird, I forget which. I was trying to be helpful but got brushed off. The birds in question were unmistakenly bald eagles and one of the nests was on a small island in a shortish tree and I had to leave the island to the end of the season to map after a very intimidating stand-off while the chicks were still in the nest.
Interesting stuff. I’ve had a look around at the sort of climate that the Joshua tree might appreciate and I think that there are areas in the Groot and Klein Karroo in South Africa which would probably suit.
Has anyone ever considered approaching the S.A. Govt. to ask if a ‘preservation reservation’ for the Joshua might be set up in the RSA?
There might even be some S. A. herbivores which could assist in seed dispersal. Who knows?
Willis Eschenbach says:
March 30, 2011 at 5:16 pm
Kev-in-Uk says:
March 30, 2011 at 3:59 pm
“‘Firstly, if a picture from google is ‘out there’ – shouldn’t his complaint be at least partly directed to them.’
No, it was properly directed here, the action was mine, and we were the ones who could (and did) respond immediately to his request.”
If you did download and store his image on another computer/server and accessed it from there that would constitute infringement, if you don’t have consent.
However it is not illegal by copyright infringement to src his image, as in linking to his site/server, assuming both servers are in the US or in the EU (not in Oz or Kiwi-kingdom neither I believe), since then the client browser is the one doing the connection so to speak. In US this was judged upon by the ninth circuit court a few years ago.
It might be considered to be immoral though since pretty much every poor bastard has to police their own digital property, as in spending time making sure ones property isn’t infringed upon by others. However, if a person has time to spend policing the internet and reading “horrendous” sites such as this, in his case according to him, even the most feeble minded of hippies then has time to learn the basic on how to protect their own digital property, which, incidentally, only needs to be done once.
It’s nice when people are nice but nice is a two way communication. It’s not nice to blame others for ones own incompetence and then go and curse ’em when they’re being nice and complies anyhow.
Why is it that CAGW hippie proponents can’t be civil and nice? Why do they have to blame everyone else for their illiteracy and incompetence?
ddpalmer says:
March 31, 2011 at 5:53 am
Quite possibly. However, the Willis Fair Use Doctrine generally requires me to take down a picture if someone asks …
w.
Chris Clark writing about himself at his blog Coyote Crossing …
“Chris began writing professionally in 1989 for Terrain, a small non-profit monthly environmental publication in Berkeley, CA. He took over the editor’s post there in 1992. By the time he left in 1997 Terrain had acquired a reputation for incisive, intelligent, and iconoclastic writing. Chris has since worked for a number of environmental news publications in print, online and radio, most prominent among them the Earth Island Journal. He’s also been a nationally syndicated garden writer with the Knight Ridder chain, his column generally appearing under the heading “The Irascible Gardener.” His resume is here.”
wow, he’s such a humble guy … and since W. is too nice to say it I will … he’s apparently a foul mouth ignorant ex-gardener with a huge chip on his narrow shoulders …
Nietzsche was a teacher’s nightmare. A lot of people don’t know this, but when he was a kid, if you handed him some scissors, he’d run around like his pantaloons were on fire. He simply would not abide by the then current theory that you shouldn’t run with scissors.
It makes me wonder how awesome he’d be when discussing AGW. I’m guessing ‘pretty awesome’.
Like averaging temperatures from disparate locales: it proves you can do arithmetic, but says nothing whatever about the physical world.
How can you possibly mistake a bald eagle for anything else? Their white heads and chocolate brown bodies are practically unmistakable. Besides, those enormous nests are unique in the natural world.
The writer mentions Shasta ground sloths and pack rats as being just about the only two herbivores in the arid regions where the Joshua Tree grows, but in fact there are others including feral horses, tortoises, antelope, deer, and even elephants. Of course I’m referring to the inventory of animals prior to the great extinction event at the boundary between the pleistocene and holocene. Whatever caused it is still an uncertainty, but that they, or their surrogates, could and do still survive and would add to the productivity of the trophic levels is not much disputed. I think we should be actively re-introducing species and their surrogates while reducing the numbers of domestic cattle that graze our wild public lands in the southwest.
doug l says:
April 2, 2011 at 11:31 am
You raise an interesting question, Doug. It’s not clear to me exactly what species would thrive, or even survive, in the conditions where the Joshua trees live. What species would you consider introducing to the area? I’ve read that the Early Asian Immigrants (aka American Indians, aka Native Americans) used to eat the seeds of the Joshua trees …
Thanks for the ideas.
w.