Featured Research

from universities, journals, and other organizations

Bones Beat Trees As Markers For Environmental Change

Date:
August 20, 2007
Source:
Michigan Technological University
Summary:
Environmental change in the Earth's atmosphere is clearly writ in the bones of wolves, scientists have discovered. To track atmospheric change caused by human activity, researchers have long studied a variety of materials, from tree rings to air trapped in glacial ice. A problem has been "noise"--natural variability caused by sampling and random events that affect atmospheric chemistry. Noise can make it hard to tease out trends from the data.

Wolf bones have proved a more reliable measure of environmental atmospheric change than tree rings, researchers at Michigan Technological University have discovered.
Credit: Photo illustration by Joseph Bump

Environmental change in the Earth’s atmosphere is clearly writ in the bones of wolves, scientists from Michigan Technological University have discovered.

Related Articles


To track atmospheric change caused by human activity, researchers have long studied a variety of materials, from tree rings to air trapped in glacial ice. A problem has been "noise"—natural variability caused by sampling and random events that affect atmospheric chemistry. Noise can make it hard to tease out trends from the data.

Joseph Bump, a PhD candidate in forest science at Michigan Tech, and his colleagues speculated that those trends would be picked up by top predators as well as by trees. And they further suspected that measurements from predators would show much less noise.

"Wolves consume many prey animals—a minimum of 150–200 moose contribute to an Isle Royale wolf’s diet over the course of its lifetime—and the prey consume a whole lot of plants," Bump explains. "Just by being who they are, wolves and other top predators increase the sample size, because they do the sampling for us."

The team studied moose and wolf bone samples dating back to 1958 from Isle Royale National Park, in Lake Superior, the site of the longest-running predator-prey study in the world. In addition, they looked at 30,000-year-old bones from the long-extinct dire wolf and prehistoric bison pulled from the La Brea tar pits in Los Angeles. They compared the trend found in the bone chronologies to trends already established for tree rings in North America.

They found that gray and dire wolves, provide a much clearer record of environmental change than either the plants, the moose or the bison.

"Since the widespread combustion of fossil fuels, we have put a human fingerprint on atmospheric carbon dioxide," Bump said. "That fingerprint shows up in trees, and it shows up in animals that eat trees, but it shows up with the least variation in the top predators."

That fingerprint has to do with the ratio between carbon-12 and carbon-13. While carbon-12 is always much more abundant in atmospheric carbon dioxide, burning fossil fuels releases even more of it. So in recent years, even more carbon-12 has been incorporated by organisms than carbon-13.

The scientists found that the carbon-12 signal improves the farther up the food chain you go. "It's noisy for trees, less noisy for moose, and even less noisy for wolves," Bump said.

"In a way, this whole study can be summed up by asking, 'How many trees does a wolf represent?'"

Their analysis opens the door to a new area of inquiry, since the bones of predators dating back dozens to thousands of years are available at natural history museums all over the world.

"Instrumental measurements of environmental variables are only available for about the past few hundred years, so this may help us understand paleo-environmental change better, and if we can understand ancient environments better, then our ability to predict future changes is improved," says Bump.

Their paper, "Stable Isotopes, Ecological Integration, and Environmental Change: Wolves Record Atmospheric Carbon Isotope Trend Better than Tree Rings," appears in the Proceedings of the Royal Society–B, published online on Aug. 7, 2007 .

The coauthors are Rolf Peterson and John Vucetich, of Michigan Tech; Kena Fox-Dobbs and Paul Koch, of the University of California at Santa Cruz; and Jeffrey Bada, of Scripps Institution of Oceanography, University of California at San Diego.

The study was funded by the National Science Foundation, the U.S. Environmental Protection Agency, the National Park Service and Earthwatch.


Story Source:

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


Cite This Page:

Michigan Technological University. "Bones Beat Trees As Markers For Environmental Change." ScienceDaily. ScienceDaily, 20 August 2007. <www.sciencedaily.com/releases/2007/08/070817210143.htm>.
Michigan Technological University. (2007, August 20). Bones Beat Trees As Markers For Environmental Change. ScienceDaily. Retrieved December 22, 2014 from www.sciencedaily.com/releases/2007/08/070817210143.htm
Michigan Technological University. "Bones Beat Trees As Markers For Environmental Change." ScienceDaily. www.sciencedaily.com/releases/2007/08/070817210143.htm (accessed December 22, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Monday, December 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Christmas Kissing Good for Health

Christmas Kissing Good for Health

Reuters - Innovations Video Online (Dec. 22, 2014) Scientists in Amsterdam say couples transfer tens of millions of microbes when they kiss, encouraging healthy exposure to bacteria. Suzannah Butcher reports. Video provided by Reuters
Powered by NewsLook.com
Brain-Dwelling Tapeworm Reveals Genetic Secrets

Brain-Dwelling Tapeworm Reveals Genetic Secrets

Reuters - Innovations Video Online (Dec. 22, 2014) Cambridge scientists have unravelled the genetic code of a rare tapeworm that lived inside a patient's brain for at least four year. Researchers hope it will present new opportunities to diagnose and treat this invasive parasite. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
New Fish Species Discovered, Setting Record for World's Deepest

New Fish Species Discovered, Setting Record for World's Deepest

Buzz60 (Dec. 22, 2014) A new species of fish is discovered living five miles beneath the ocean surface, making it the deepest living fish on earth. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Earthworms Provide Cancer-Fighting Bacteria

Earthworms Provide Cancer-Fighting Bacteria

Reuters - Innovations Video Online (Dec. 21, 2014) Polish scientists isolate bacteria from earthworm intestines which they say may be used in antibiotics and cancer treatments. Suzannah Butcher reports. Video provided by Reuters
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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