Why are some species of plants and animals favored by natural selection? And why does natural selection not favor other species similarly?
According to a UC Riverside-led research team, the answer lies in the rate of metabolism of a species – how fast a species consumes energy, per unit mass, per unit time.
The researchers studied 3006 species, the largest number of species ever analyzed in a single study. The species list encompasses much of the range of biological diversity on Earth – from bacteria to elephants, and algae to sapling trees.
To the researchers' surprise, they found the mean metabolic rate of the species at rest fell on a narrow range of values – 0.3 to 9 Watts per kilogram.
"This narrow range is in dramatic contrast to the 20 orders of magnitude difference in the body mass of the species we studied," said Bai-Lian Li, a professor of ecology at UC Riverside, who led the study along with two colleagues. "At physiological rest, the biosphere appears to run, on average, predominantly at the optimal rate defined by this narrow range of values. This remarkable phenomenon is likely associated with the pervasive biochemical universality of living matter, and could provide us with clues to understanding how life is organized."
Study results appear in the Nov. 4 issue of the Proceedings of the National Academy of Sciences.
According to Li, the metabolic optimum explains the ubiquitous and seemingly unrelated features of life organization we see all around us – complex adaptations such as animal breathing and flat, green leaves.
"Organisms whose designs fit the physiological window have been favored by natural selection across all of life's major kingdoms," he said. "This observed, narrow range might therefore be considered as the preferred, optimal range for the functioning of living matter as a whole."
Unlike the genetic code and protein composition, metabolic rate cannot be inherited from a common ancestor. Rather, a particular range of metabolic rates is maintained by natural selection.
"Species had to invent diverse tricks to remain near the metabolic optimum, from which the progressive evolutionary increase in body size – from prokaryotes to largest vertebrates and plants – was continually taking them away," Li said.
He was joined in the study by co-leaders Anastassia M. Makarieva and Victor G. Gorshkov of the Russian Academy of Sciences, St. Petersburg. Their co-authors on the research paper are Steven L. Chown of Stellenbosch University, South Africa; Peter B. Reich of the University of Minnesota, St. Paul; and Valery M. Gavrilov of Moscow State University, Russia.
Iqbal Pittalwala | EurekAlert!
Do microplastics harbour additional risks by colonization with harmful bacteria?
05.04.2018 | Leibniz-Institut für Ostseeforschung Warnemünde
Rutgers-led innovation could spur faster, cheaper, nano-based manufacturing
14.02.2018 | Rutgers University
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.
Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...
In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
20.04.2018 | Physics and Astronomy
20.04.2018 | Interdisciplinary Research
20.04.2018 | Physics and Astronomy