Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Richness of Ocean Life Reflected in a Test Tube

11.03.2005


Ecologists know that when it comes to habitats, size matters, and now a new study finds that contrary to earlier beliefs, that maxim holds true right down to the tiny plants at the bottom of many oceanic and freshwater food chains.



The study, conducted by University of Florida, University of Kansas and University of Texas researchers, is important because it shows that tiny microbes follow the same diversity patterns as larger organisms, said Robert D. Holt, a UF professor of zoology and one of the study’s authors. The study appears in the current issue of the Proceedings of the National Academy of Sciences.

In addition, species diversity is “a reflection of the richness of life,” Holt said. Though there are few rigorous mathematical laws in ecology, that relationship between the size of a habitat and the range of species in it has been observed for nearly all organisms. “Understanding the diversity of life itself is a basic scientific question, in the same way as understanding the causes for the diversity of human civilizations around the world, or understanding questions like the origin of the universe,” Holt said.


Earlier studies have suggested that the diversity-habitat size rule may not hold true for one of the most ubiquitous species in the world: phytoplankton, a group of microscopic algae afloat in the world’s oceans, seas and lakes.

In contrast, the new study demonstrates that the range of phytoplankton species in an ecosystem increases with ecosystem size according to a general mathematical rule. The study also finds that this holds true whether the system is a laboratory test tube or an ocean. “A skeptic might say, ‘I cannot conceive of how a bottle in the lab that holds as much as a can of beer can tell me anything about Lake Okeechobee,’” said Val Smith, professor of ecology and evolutionary biology at the University of Kansas and the lead author on the study.

But for at least this one principle, that connection exists, Smith said. “Species diversity scales upward with size,” he said.

The researchers analyzed pre-existing scientific data on phytoplankton species in 142 oceans, lakes and natural ponds worldwide, ranging from a few square inches to millions of square miles, and from 239 laboratory test tubes, flasks and beakers.
They found that not only did a correlation between species diversity and habitat area exist for natural water bodies like lakes and oceans, but that an identical pattern exists for experimental ecosystems such as test tubes and laboratory tanks.

“Interestingly, that must say something about the mechanism that controls species diversity,” Smith said. “If it works for (habitats ranging from) little tiny flasks on the desktop to the Arctic Ocean, that says something about how size really matters. We need to figure out which elements of size are the dominant factors that cause this pattern.”

Some of the factors known to influence species variety within a habitat are simply size-dependent, Holt said. For example, some species, such as sharks, simply require more space to survive. “There’s not enough for them to eat in a small lake,” he said.

Bigger ecosystems also will tend to have a greater variety of mini-habitats within them. A large lake contains both shallow and deep areas and can therefore accommodate a greater variety of organisms than a shallow pond, he said. And with the larger total population sizes found in a larger habitat, overall species extinction rates are likely to be lower.

Other possible causes are related to interactions between ecosystems. Larger habitats are bigger targets for the wind or for migrating birds that can transfer algal cells. And larger freshwater bodies tend to have higher river inflows, which can also transport more algae.

For the phytoplankton, the most important factors influencing species diversity are not yet certain, Holt said. However, because the experimental ecosystems were cut off from the surrounding area but the diversity trend was nearly identical to that of the open natural systems, internal factors may play a stronger role, he said. “You’re restricting the processes that could be acting on them, but you’re still seeing this scaling effect,” he said.

Previous studies have looked for a species-area relationship in phytoplankton but found none, possibly because their sample sizes were too small, Smith said. The current study used data from samples spanning more than 15 orders of magnitude, compared with three or four in previous studies.

The results are encouraging for scientists who want to get a handle on scientific questions in hard-to-study, ocean-scale systems, Holt said.

“By studying these smaller systems we may be getting insight into much larger systems where it’s impossible to do experiments and where it’s really hard even to get the raw data,” he said.

Smith agreed. “The fact that lab-scale systems behave similarly to larger natural systems gives us hope that if we ask questions at the lab scale, properly phrased, we can get reasonable answers.”

| newswise
Further information:
http://www.ufl.edu

More articles from Ecology, The Environment and Conservation:

nachricht Safeguarding sustainability through forest certification mapping
27.06.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht Dune ecosystem modelling
26.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

Im Focus: The proton precisely weighted

What is the mass of a proton? Scientists from Germany and Japan successfully did an important step towards the most exact knowledge of this fundamental constant. By means of precision measurements on a single proton, they could improve the precision by a factor of three and also correct the existing value.

To determine the mass of a single proton still more accurate – a group of physicists led by Klaus Blaum and Sven Sturm of the Max Planck Institute for Nuclear...

Im Focus: On the way to a biological alternative

A bacterial enzyme enables reactions that open up alternatives to key industrial chemical processes

The research team of Prof. Dr. Oliver Einsle at the University of Freiburg's Institute of Biochemistry has long been exploring the functioning of nitrogenase....

Im Focus: The 1 trillion tonne iceberg

Larsen C Ice Shelf rift finally breaks through

A one trillion tonne iceberg - one of the biggest ever recorded -- has calved away from the Larsen C Ice Shelf in Antarctica, after a rift in the ice,...

Im Focus: Laser-cooled ions contribute to better understanding of friction

Physics supports biology: Researchers from PTB have developed a model system to investigate friction phenomena with atomic precision

Friction: what you want from car brakes, otherwise rather a nuisance. In any case, it is useful to know as precisely as possible how friction phenomena arise –...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

The technology with a feel for feelings

12.07.2017 | Event News

Leipzig HTP-Forum discusses "hydrothermal processes" as a key technology for a biobased economy

12.07.2017 | Event News

 
Latest News

Researchers create new technique for manipulating polarization of terahertz radiation

20.07.2017 | Information Technology

High-tech sensing illuminates concrete stress testing

20.07.2017 | Materials Sciences

First direct observation and measurement of ultra-fast moving vortices in superconductors

20.07.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>