Why is the diversity of animals and plants so unevenly distributed on our planet? An international research team headed by the University of Würzburg has provided new data on this core issue of ecology. They found biodiversity to be driven by temperature.
The diversity of plants and animals in Earth's arctic regions is moderate. Tropical latitudes in contrast are teeming with different species where new organisms are being discovered all the time.
5,895-m-high Mount Kilimanjaro with its different climate zones is an important research field for ecologists.
(Photo: Anna Kühnel)
What is the cause of this uneven distribution? Why are the tropics home to more species than higher latitudes? "This question has intrigued ecologists for some time," says Professor Ingolf Steffan-Dewenter from the University of Würzburg's Biocenter. "Already about ten years ago, the publishers of Science declared this to be one of the 25 most important questions of science to be answered yet."
Several hypotheses circulating
To date, this core question has been subject to controversy. One hypothesis, for instance, is that the primary productivity of a habitat is ultimately decisive for the number of species living there. Simply put: "A larger cake can sustain more species than a small one," explains Würzburg ecologist Dr. Marcell Peters. Another hypothesis assumes that the rate of evolution and speciation depend on temperature. According to this assumption, more species thrive in a warmer climate than in a cold one.
So far, these hypotheses have been examined usually by focusing on selected groups of species: For example, the studies observed only birds, bees, ants or ferns and analysed their diversity in different regions of the world, e.g. in North America, Europe or along elevational gradients in the Alps. "Some studies supported one hypothesis, whereas others backed another assumption," Peters says and states that it is still a long way from establishing a "general rule" which ecologists are aiming for.
Unique study conducted at Mount Kilimanjaro
In the journal "Nature Communications" Peters and the team of the Research Unit "FOR1246" funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) now present a new study which is unique so far and is the synthesis of four years of working: "On Mount Kilimanjaro, one of Earth's largest climatic gradients, we observed so many animal and plant groups in parallel as never before," the researcher says.
Overall, the team examined eight groups of plants and 17 groups of animals, from bees to bats. 38 scientists from Germany, Tanzania and other countries participated in the large-scale study; they were supported by around 50 local drivers, carriers and other assistants. "We had to climb in mountainous areas for several days to reach the highest study sites," Peters says.
The area of study stretched from the savannahs at the foot of the mountain to the habitats at an altitude of 4,550 metres that barely sustain plants. The data across all groups were collected over the same areas and in the same period of time, respectively. "This approach allowed us to not only analyse the biodiversity of each individual group, but also that of whole communities.”
Diversity increases with temperature
The study revealed that biodiversity in communities is mainly determined by temperature. The warmer it is, the greater the diversity. "The more groups of animals and plants you investigate in parallel, the greater the significance of temperature for explaining biodiversity, whereas the importance of all other variables decreases accordingly."
The scientists believe that this is strong evidence supporting the assumption that temperature is actually more decisive for distribution patterns of overall biodiversity than productivity or size of habitats.
"Predictors of elevational biodiversity gradients change from single taxa to the multi-taxa community level", Peters et al., Nature Communications 7: 13736, DOI 10.1038/ncomms13736 (2016)
Dr. Marcell Peters, Department of Animal Ecology and Tropical Biology, Biocenter, University of Würzburg, T +49 931 31-83330, firstname.lastname@example.org
http://www.zoo3.biozentrum.uni-wuerzburg.de/team/peters0/ Website of Dr. Marcell Peters
Robert Emmerich | Julius-Maximilians-Universität Würzburg
Newly designed molecule binds nitrogen
23.02.2018 | Julius-Maximilians-Universität Würzburg
Atomic Design by Water
23.02.2018 | Max-Planck-Institut für Eisenforschung GmbH
A newly developed laser technology has enabled physicists in the Laboratory for Attosecond Physics (jointly run by LMU Munich and the Max Planck Institute of Quantum Optics) to generate attosecond bursts of high-energy photons of unprecedented intensity. This has made it possible to observe the interaction of multiple photons in a single such pulse with electrons in the inner orbital shell of an atom.
In order to observe the ultrafast electron motion in the inner shells of atoms with short light pulses, the pulses must not only be ultrashort, but very...
A group of researchers led by Andrea Cavalleri at the Max Planck Institute for Structure and Dynamics of Matter (MPSD) in Hamburg has demonstrated a new method enabling precise measurements of the interatomic forces that hold crystalline solids together. The paper Probing the Interatomic Potential of Solids by Strong-Field Nonlinear Phononics, published online in Nature, explains how a terahertz-frequency laser pulse can drive very large deformations of the crystal.
By measuring the highly unusual atomic trajectories under extreme electromagnetic transients, the MPSD group could reconstruct how rigid the atomic bonds are...
Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...
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...
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...
15.02.2018 | Event News
13.02.2018 | Event News
12.02.2018 | Event News
23.02.2018 | Physics and Astronomy
23.02.2018 | Health and Medicine
23.02.2018 | Physics and Astronomy