Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

What makes life go at the tropics?

29.05.2008
PNAS study points to heat, not light, as engine driving biodiversity
What causes tropical life to thrive: temperature, or sunlight?

The answer is not necessarily “both.” According to a study published online this week in PNAS Early Edition, the explosion of species at the tropics has much more to do with warmth than with light.

“The diversity was unrelated to productivity (from photosynthesis), but it was strongly related to temperature,” said University of Southern California biologist Jed Fuhrman, who led a group that analyzed bacterial samples from warm and cold oceans.

Fuhrman’s group found far greater diversity in samples taken near the equator. In particular, samples from low-productivity waters still contained many bacterial species, suggesting that photosynthesis has little influence on diversity.

Many researchers have tried to separate the influence of temperature and sunlight, Fuhrman said, but have found it hard to do by studying higher organisms.

Bacteria are ideal subjects because of their wide distribution and the recent availability of genetic fingerprinting, he added.

The question of what drives diversity is important to biologists who seek to uncover the basic rules governing life.

“Is diversity ruled by fundamental laws, and if so, what is the basis of them?” Fuhrman asked.

The so-called kinetic law links the rates of metabolism, reproduction and many other biological processes to the motion of atoms and molecules. Such motion increases with temperature, presumably speeding up the biological processes.

Fuhrman calls this “the Red Queen runs faster when she is hot” hypothesis.

Productivity also is thought to promote diversity by increasing the food supply. This is “the larger pie can be divided into more pieces” hypothesis.

The two hypotheses may both be valid, Fuhrman said, but his group’s results show that “the kinetics of metabolism, setting the pace for life, has strong influence on diversity.”

Biologists have known for centuries that animal and plant biodiversity is greatest at the tropics, though they have not agreed on whether temperature or productivity was the cause.

The Fuhrman group is the first to show that bacteria follow the same pattern. And as the PNAS study shows, bacteria are useful vehicles for probing the causes of biodiversity.

Fuhrman, holder of the McCulloch-Crosby Chair for Marine Biology in the USC College of Letters, Arts and Sciences, has been studying bacteria since the early 1980s, when new instruments and techniques greatly improved scientists’ ability to identify microbial species.

Since then, marine biologists have realized that bacteria play a dominant role in the oceans. More than half the carbon dioxide respired by marine organisms comes from bacteria, Fuhrman said. Bacteria also comprise most of the diversity on earth, control vital biogeochemical cycles, and form an integral part of the food chain.

“I study them because, even though they’re invisible, they’re incredibly important,” Fuhrman said.

Carl Marziali | EurekAlert!
Further information:
http://www.usc.edu

More articles from Ecology, The Environment and Conservation:

nachricht Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel

nachricht Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)

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: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Major discovery in controlling quantum states of single atoms

20.02.2018 | Physics and Astronomy

New printing technique uses cells and molecules to recreate biological structures

20.02.2018 | Life Sciences

New tech for commercial Lithium-ion batteries finds they can be charged 5 times fast

20.02.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>