Temperature explains much of why cold-blooded organisms such as fish, amphibians, crustaceans, and lizards live longer at higher latitudes than at lower latitudes, according to research published this week in the Proceedings of the National Academy of Sciences (PNAS) online.
Assistant Professor Dr. Stephan Munch and Ph.D. candidate Santiago Salinas, both of Stony Brook University's School of Marine and Atmospheric Sciences (SoMAS), found that for a diverse range of species whose body temperatures vary with the temperature of their surroundings, ambient temperature is the dominant factor controlling geographic variation of lifespan within species.
"We were intrigued by the fact that that pearl mussels in Spain have a maximum lifespan of 29 years, while in Russia, individuals of the same species live nearly 200 years," said Dr. Munch. "We wondered how a relatively small difference in latitude (Spain 43ºN and Russia 66ºN) could have such a drastic impact on lifespan. While one might expect that local adaptations or geographic variations in predator and food abundance would account for this disparity, we wanted to see whether the geographical variation in lifespan that we see in all sorts of species has a common physiological basis in temperature."
Munch and Salinas looked at lifespan data from laboratory and field observations for over 90 species from terrestrial, freshwater, and marine environments. They studied organisms with different average longevities--from the copepod Arcartia tonsa, which has an average lifespan of 11.6 days, to the pearl mussel Margaritifera margaritifera, which has an average lifespan of 74 years. They found that across this wide range of species, temperature was consistently exponentially related to lifespan.
The relationship between temperature and lifespan that Munch and Salinas found through data analysis was strikingly similar to the relationship that the metabolic theory of ecology (MTE) predicts. The MTE is a modeling framework that has been used to explain the way in which life history, population dynamics, geographic patterns, and other ecological processes scale with an animal's body size and temperature.
"You can think of an animal as a beaker in which chemical reactions are taking place," said Salinas. "The same rules that apply to a liquid inside a beaker should apply to animals. Chemists have a relationship for how an increase in temperature will speed up reaction rates, so the MTE borrows that relationship and applies it--with some obvious caveats--to living things."
The lifespan in 87% of the free-living species Munch and Salinas studied varied as predicted by the MTE. Yet after removing the effect of temperature, there was still considerable variation in lifespan within species, indicating that other, local factors still play a role in determining lifespan.
"It is interesting to consider how cold-blooded species are likely to react in the face of global warming," said Salinas. "Because of the exponential relationship between temperature and lifespan, small changes in temperature could result in relatively large changes in lifespan. We could see changes to ecosystem structure and stability if cold-blooded species change their life histories to accommodate warmer temperatures but warm-blooded species do not."
Leslie Taylor | EurekAlert!
Scientists produce a new roadmap for guiding development & conservation in the Amazon
09.12.2016 | Wildlife Conservation Society
Successful calculation of human and natural influence on cloud formation
04.11.2016 | Goethe-Universität Frankfurt am Main
Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.
Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...
In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.
Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...
Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...
A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.
Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...
In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.
“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
09.12.2016 | Life Sciences
09.12.2016 | Ecology, The Environment and Conservation
09.12.2016 | Health and Medicine