Navigation Links
Uncertain future for Joshua trees projected with climate change
Date:3/24/2011

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.


'/>"/>

Contact: Lara Schmit
lschmit@usgs.gov
928-556-7327
United States Geological Survey
Source:Eurekalert

Related biology news :

1. A positive step in the face of uncertainty
2. Apes unwilling to gamble when odds are uncertain
3. Major moral decisions use general-purpose brain circuits to manage uncertainty
4. Shellfish face an uncertain future in a high CO2 world
5. Dealing with taxonomic uncertainty for threatened and endangered species
6. Research brings habitat models into the future
7. Science for Our Nations Energy Future: Energy Frontier Research Centers Summit & Forum
8. Penn research identifies potential mechanisms for future anti-obesity drugs
9. Putting trees on farms fundamental to future agricultural development
10. Cell Press wins prestigious PROSE Award for Article of the Future
11. Pollutants in aquifers may threaten future of Mexicos fast-growing Riviera Maya
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:2/8/2017)... , Feb. 8, 2017 About Voice Recognition ... to match it against a stored voiceprint template. ... pitch, cadence, and tone are compared to distinguish ... hardware installation, as most PCs already have a ... transactions. Voice recognition biometrics are most likely to ...
(Date:2/7/2017)... Minn. , Feb. 7, 2017   MedNet ... supports the entire spectrum of clinical research, is pleased ... iMedNet , its innovative, highly flexible and award ... iMedNet customers. iMedNet is a proven ... provides Electronic Data Capture (EDC), but also delivers an ...
(Date:2/3/2017)... A new independent identity strategy consultancy firm ... . Designed to fill a critical niche in technical ... partners Mark Crego and Janice Kephart ... identity expertise that span federal governments, the 9/11 Commission, ... combined expertise has a common theme born from a ...
Breaking Biology News(10 mins):
(Date:2/24/2017)... CA (PRWEB) , ... February 24, 2017 , ... Delpor, ... a $224K grant from the National Institute of Mental Health (NIMH) for the further ... on Delpor’s PROZOR technology and is expected to deliver therapeutic levels of ...
(Date:2/24/2017)... -- Aethlon Medical, Inc. (Nasdaq: AEMD ), today ... CEO, Jim Joyce . In a ... Bill Gates warned world leaders that a ... weapons. Mr. Gates expressed his concern, which is also ... terrorists have access to the necessary tools to design ...
(Date:2/24/2017)... Feb. 24, 2017 China Cord Blood Corporation (NYSE: ... leading provider of cord blood collection, laboratory testing, hematopoietic ... announced its unaudited financial results for the third quarter ... December 31, 2016. Third Quarter of Fiscal ... quarter of fiscal 2017 increased by 18.6% to RMB200.9 ...
(Date:2/24/2017)... Feb. 24, 2017  VWR Corporation (NASDAQ: VWR), the leading ... and production customers, today reported its financial results for the ... Highlights: 4Q16 record quarterly net ... on an organic basis. 4Q16 ... organic basis, while the Americas net sales increased 2.5%, or ...
Breaking Biology Technology: