The animals and plants of our planet are becoming extinct under the pressure of civilization. The scientists have counted that one species vanishes from Earth every hour. The mammoth, passenger pigeon, gare-fowl, Steller`s sea cow - these are the most well-known of extinct species, but hundreds of species are next in turn. Can the scientists forecast what species is the first in this succession and what species is not under the threat of complete extinction? If the answer is known, the effort and funds intended for the preservation of natural resources could be distributed correctly. Leonard Polishchuk, Ph. D. (Biology), research assistant of the Chair of General Ecology, Faculty of Biology, Lomonosov Moscow State University, has found a mathematical index of animal vulnerability.
It is common knowledge that the species of large animals that propagate themselves slowly and produce scarce posterity extinct earlier than others. Therefore, Leonard Polishchuk was looking for the characteristic of extinction risk among common demographic and ecological parameters. The researcher analyzed several parameters for 90 species mammal inhabiting the territory of the former USSR: life interval, quantity of litter, body weight of a sexually mature female, annual prolificacy and the number of posterity that each specific animal species produces within the entire lifetime. Applying the logistic regression method, he compared the above parameters to the probability of these species` registration in the Red Book. The most appropriate characteristic has appeared to be natural annual prolificacy, i.e. the number of daughters born by a female within a year.
The leaders of this index have turned out to be the rodents: common shrew (11.4), rabbit (10.5), Pallas` pika and steppe mouse-hare (8.8 è 7.9), field mouse (7.7), Alpine hare and European hare (5.0 è 4.4) - these species are well-known for their vitality.
About one third of all investigated species is characterized by the index exceeding 2.9. Almost all the species registered in the Red Book are grouped closer to the end of the list - their production/mortality ratio is lower than the above value. The list is ended by the walrus (0.17), bison (0.20), and the sea-otter (0.25), which were on the verge of extinction in the 19th century.
Elena Krasnova | Informnauka
Multi-institutional collaboration uncovers how molecular machines assemble
02.12.2016 | Salk Institute
Fertilized egg cells trigger and monitor loss of sperm’s epigenetic memory
02.12.2016 | IMBA - Institut für Molekulare Biotechnologie der Österreichischen Akademie der Wissenschaften GmbH
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...
The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.
The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...
Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water
In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...
The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...
16.11.2016 | Event News
01.11.2016 | Event News
14.10.2016 | Event News
02.12.2016 | Medical Engineering
02.12.2016 | Agricultural and Forestry Science
02.12.2016 | Physics and Astronomy