Featured Research

from universities, journals, and other organizations

Star of Africa's savanna ecosystems may be the lowly termite: Regularly spaced termite mounds are key to maintaining ecological function

Date:
May 26, 2010
Source:
Harvard University
Summary:
The majestic animals most closely associated with the African savanna -- fierce lions, massive elephants, towering giraffes -- may be relatively minor players when it comes to shaping the ecosystem. The real king of the savanna appears to be the termite, say ecologists who've found that these humble creatures contribute mightily to grassland productivity in central Kenya via a network of uniformly distributed colonies.

This is a soldier termite in a fungal comb. These termites are rarely seen above ground, but their subterranean activities support the productivity and biodiversity of African savannas.
Credit: Robert M. Pringle

The majestic animals most closely associated with the African savanna -- fierce lions, massive elephants, towering giraffes -- may be relatively minor players when it comes to shaping the ecosystem.

The real king of the savanna appears to be the termite, say ecologists who've found that these humble creatures contribute mightily to grassland productivity in central Kenya via a network of uniformly distributed colonies. Termite mounds greatly enhance plant and animal activity at the local level, while their even distribution over a larger area maximizes ecosystem-wide productivity.

The finding, published in the journal PLoS Biology, affirms a counterintuitive approach to population ecology: Often it's the small things that matter most.

"It's not always the charismatic predators -- animals like lions and leopards -- that exert the greatest control on populations," says Robert M. Pringle, a research fellow at Harvard University. "As E.O. Wilson likes to point out, in many respects it's the little things that run the world. In the case of the savanna, it appears these termites have tremendous influence and are central to the functioning of this ecosystem."

Prior research on the Kenya dwarf gecko initially drew Pringle's attention to the peculiar role of grassy termite mounds, which in this part of Kenya are some 10 meters in diameter and spaced some 60 to 100 meters apart. Each mound teems with millions of termites, who build the mounds over the course of centuries.

After observing unexpectedly high numbers of lizards in the vicinity of mounds, Pringle and his colleagues began to quantify ecological productivity relative to mound density. They found that each mound supported dense aggregations of flora and fauna: Plants grew more rapidly the closer they were to mounds, and animal populations and reproductive rates fell off appreciably with greater distance.

What was observed on the ground was even clearer in satellite imagery. Each mound -- relatively inconspicuous on the Kenyan grassland -- stood at the center of a burst of floral productivity. More importantly, these bursts were highly organized in relation to one another, evenly dispersed as if squares on a checkerboard. The result, says Pringle, is an optimized network of plant and animal output closely tied to the ordered distribution of termite mounds.

"In essence, the highly regular spatial pattern of fertile mounds generated by termites actually increases overall levels of ecosystem production. And it does so in such a profound way," says Todd M. Palmer, assistant professor of biology at the University of Florida and an affiliate of the Mpala Research Centre in Nanyuki, Kenya. "Seen from above, the grid-work of termite mounds in the savanna is not just a pretty picture. The over-dispersion, or regular distribution of these termite mounds, plays an important role in elevating the services this ecosystem provides."

The mechanism through which termite activity is transformed into far-reaching effects on the ecosystem is a complex one. Pringle and Palmer suspect termites import coarse particles into the otherwise fine soil in the vicinity of their mounds. These coarser particles promote water infiltration of the soil, even as they discourage disruptive shrinking and swelling of topsoil in response to precipitation or drought.

The mounds also show elevated levels of nutrients such as phosphorus and nitrogen. All this beneficial soil alteration appears to directly and indirectly mold ecosystem services far beyond the immediate vicinity of the mound.

While further studies will explore the mechanism through which these spatial patterns of termite mounds emerge, Pringle and Palmer suggest that the present work has implications beyond the basic questions of ecology.

"Termites are typically viewed as pests, and as threats to agricultural and livestock production," Pringle says. "But productivity -- of both wild and human-dominated landscapes -- may be more intricately tied to the pattern-generating organisms of the larger natural landscape than is commonly understood."

The findings also have important implications for conservation, Palmer says.

"As we think restoring degraded ecosystems, as we think about restoring coral reefs, or restoring plant communities, this over-dispersed pattern is teaching us something," he says. "It's saying we might want to think about doing our coral restoration or plant restoration in a way that takes advantage of this ecosystem productivity enhancing phenomenon."

Pringle and Palmer's co-authors on the PLoS Biology paper are Daniel F. Doak of the Mpala Research Centre and the University of Wyoming; Alison K. Brody of the Mpala Research Centre and the University of Vermont; and Rudy Jocqué of the Royal Museum for Central Africa in Tervuren, Belgium. Their work was supported by the Sherwood Family Foundation and the National Science Foundation.


Story Source:

The above story is based on materials provided by Harvard University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Pringle RM, Doak DF, Brody AK, Jocqué R, Palmer TM. Spatial Pattern Enhances Ecosystem Functioning in an African Savanna. PLoS Biology, 2010; 8 (5): e1000377 DOI: 10.1371/journal.pbio.1000377

Cite This Page:

Harvard University. "Star of Africa's savanna ecosystems may be the lowly termite: Regularly spaced termite mounds are key to maintaining ecological function." ScienceDaily. ScienceDaily, 26 May 2010. <www.sciencedaily.com/releases/2010/05/100525171229.htm>.
Harvard University. (2010, May 26). Star of Africa's savanna ecosystems may be the lowly termite: Regularly spaced termite mounds are key to maintaining ecological function. ScienceDaily. Retrieved April 20, 2014 from www.sciencedaily.com/releases/2010/05/100525171229.htm
Harvard University. "Star of Africa's savanna ecosystems may be the lowly termite: Regularly spaced termite mounds are key to maintaining ecological function." ScienceDaily. www.sciencedaily.com/releases/2010/05/100525171229.htm (accessed April 20, 2014).

Share This



More Earth & Climate News

Sunday, April 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Drought Concerns May Hurt Lake Tourism

Drought Concerns May Hurt Lake Tourism

AP (Apr. 18, 2014) — Operators of recreational businesses on western reservoirs worry that ongoing drought concerns will keep boaters and other visitors from flocking to the popular summer attractions. (April 18) Video provided by AP
Powered by NewsLook.com
Man Claims He Found Loch Ness Monster With... Apple Maps?

Man Claims He Found Loch Ness Monster With... Apple Maps?

Newsy (Apr. 18, 2014) — Andy Dixon showed the Daily Mail a screenshot of what he believes to be the mythical beast swimming just below the lake's surface. Video provided by Newsy
Powered by NewsLook.com
First Ever 'Female Penis' Discovered In Animal Kingdom

First Ever 'Female Penis' Discovered In Animal Kingdom

Newsy (Apr. 18, 2014) — Not only are these newly discovered bugs' sex organs reversed, but they also mate for up to 70 hours. Video provided by Newsy
Powered by NewsLook.com
Ark. Man Finds 6-Carat Diamond At State Park

Ark. Man Finds 6-Carat Diamond At State Park

Newsy (Apr. 18, 2014) — An Arkansas man has found a nearly 6.2-carat diamond, which he dubbed "The Limitless Diamond," at the Crater of Diamonds State Park. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins