Navigation Links
New clues found linking larger animals to colder climates
Date:2/24/2010

HOUSTON, Feb. 24, 2010 Thanks to a pair of University of Houston researchers who found a possible new solution to a 163-year-old puzzle, ecological factors can now be added to physiology to explain why animals grow bigger in the cold.

Their results were published in the February issue of the American Naturalist, offering new insight to Bergmann's rule that animals grow larger at high, cold latitudes than their counterparts closer to the equator. While traditional explanations have been based on body temperature being the driving force of this phenomenon, this group of community ecologists hypothesize that better food makes high-latitude animals bigger.

Chuan-Kai Ho, a Ph.D. graduate from UH in ecology and evolution, his adviser and UH professor of biology and biochemistry Steven Pennings, and their collaborator Thomas Carefoot from the University of British Columbia opened up a new line of study into Bergmann's rule. The research program in Pennings' lab over the last decade has offered the most extensive work done on the general problem of latitudinal variation in plant-herbivore interactions. This latest finding from Pennings' groundbreaking research at UH on this subject came from one of Ho's doctoral dissertation chapters.

"Because the American Naturalist is one of the top journals in our field, publishing at this level is a mark of great success for a Ph.D. student," Pennings said. "It's also a reflection of the strength of our graduate program in the ecology and evolution division of UH's department of biology and biochemistry."

Ho, now a postdoctoral student at Texas A&M at Galveston's Armitage & Quigg Laboratory, also has another chapter from his UH dissertation on salt marsh food webs published in Ecology, another top journal in the field. Pennings received a doctoral dissertation improvement grant for Ho in 2007-2008 from the National Science Foundation that provided funding for Ho to run chemical analyses on leaves from different latitudes to assess their nutritional content.

Studying three different plant-eating species grasshoppers, planthoppers and sea snails collected from along the Atlantic coast to Japan, respectively, the researchers fed these herbivores plants from both high and low latitudes and found that they all grew better when fed plants from the higher latitudes. This indicates that Bergmann's rule could reflect that plants from high latitudes provide better food than those from low latitudes. These latest findings, according to Ho, indicate that studies of Bergmann's rule should consider ecological interactions in addition to the more traditional theories of physiology based on responses to temperature.

Over the years, work in Pennings' lab has shown that, although low-latitude plants are less nutritious and better protected by chemical defenses, they experience heavy damage from herbivores, which are more abundant at low latitudes. Future study, Pennings adds, should focus on why there are more herbivores at lower latitudes despite the lower-quality food sources. A likely explanation is that herbivore populations are limited at high latitudes by a short growing season and high death rates during cold winters.

"While the explanations discovered in our current study only apply to herbivores, it may be that carnivores and omnivores also might grow larger as a consequence of eating larger herbivores," Ho said. "Examining such patterns and underlying mechanisms in nature will help us understand what currently is going on and what might happen down the line to our ecosystems."


'/>"/>

Contact: Lisa Merkl
lkmerkl@uh.edu
713-743-8192
University of Houston
Source:Eurekalert  

Related medicine news :

1. Investigators uncover intriguing clues to why persistent acid reflux sometimes turns into cancer
2. Online Epidemic Gives Clues to Bird Flu Spread
3. New knock-out gene model provides molecular clues to breast cancer
4. New clues to breast cancer development in high-risk women
5. Clues to Cell Death Could Fight Disease
6. Genes Give Clues to Newborn Lung Disease
7. Mouse Study Gives Clues to Colitis
8. VivoMetrics LifeShirt Going to South Pole to Uncover Clues to High-Altitude Illness
9. Protein Gives Clues to Pancreatic Cancer
10. A longer-living, healthier mouse that could hold clues to human aging
11. Clues to ensuring anti-HIV drugs are taken in Africa
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
New clues found linking larger animals to colder climates
(Date:6/25/2016)... , ... June 25, 2016 , ... Austin residents seeking ... American College of Mohs Surgery and to Dr. Russell Peckham for medical and surgical ... effective treatment for skin cancer. The selective fellowship in Mohs Micrographic Surgery completed by ...
(Date:6/25/2016)... (PRWEB) , ... June 25, 2016 , ... ... athletes and non-athletes recover from injury. Recently, he has implemented orthobiologic procedures as ... City area —Johnson is one of the first doctors to perform the treatment. ...
(Date:6/24/2016)... ... 2016 , ... June 19, 2016 is World Sickle Cell Observance Day. In ... benefits of holistic treatments, Serenity Recovery Center of Marne, Michigan, has issued ... Sickle Cell Disease (SCD) is a disorder of the red blood cells, which can ...
(Date:6/24/2016)... ... June 24, 2016 , ... Comfort Keepers® of San Diego, CA is excited ... To Recovery® program to drive cancer patients to and from their cancer treatments. ... highest quality of life and ongoing independence. Getting to and from medical treatments ...
(Date:6/24/2016)... (PRWEB) , ... June 24, 2016 , ... ... client, The Grove Investment Group (TGIG), has initiated cultivation and processing operations at ... Las Vegas and Pahrump, Nevada. , Puradigm is the manufacturer of a complete ...
Breaking Medicine News(10 mins):
(Date:6/23/2016)... June 23, 2016 Research and Markets ... Issue 52" report to their offering. ... treatment creates a favourable commercial environment for MedImmune to enter. ... base that will serve to drive considerable growth for effective ... serve to cap sales considerably, but development is still in ...
(Date:6/23/2016)... , , , WHEN: ... , , , , LOCATION: , , , Online, with ... , EXPERT PANELISTS:  , , , Frost & Sullivan,s Global Vice ... Senior Industry Analyst, Divyaa Ravishankar and Unmesh Lal, Program Manager , ... industry is witnessing an exceptional era. Several new demand spaces, such ...
(Date:6/23/2016)... Colombia , June 23, 2016  Astellas today announced the establishment of Astellas Farma Colombia (AFC), a new ... affiliate in Latin America . ... ... ... ...
Breaking Medicine Technology: