Brown fat plays an important role in newborn mammals, including our own children, since this tissue helps the newborn to maintain its body temperature by burning fat, which converts into heat. The protein UCP1 (Uncoupling Protein 1) has a key role in this energy conversion, which takes place in the cell mitochondria.
Piglets are sensitive to cold and shudder in order to maintain their body heat. No brown fat or UCP1 protein has previously been found in domesticated pigs. In a new study, Frida Berg and her colleagues have been able to show that the UCP1 gene was shut down about 20 million years ago in an ancestor of the wild boar. These scientists have found four different mutations, each of which would be sufficient to knock out the function of the protein.
“This ancestor of pigs thereby lost the ability to use brown fat to maintain body temperature after birth. A reasonable explanation for this is that brown fat was not essential during a period in the evolution of pigs, when it lived in a warm climate,” says Leif Andersson, who directs the research team.
The ancestor of the domesticated pig, the wild boar, is the only pig that lives in cold climates. All other species, such as the wart hog, live in tropical or subtropical climates. The wild boar has compensated for the loss of brown fat by a series of adaptations for survival in a cold climate. It is the only hoofed animal that builds a den when it is time to give birth (Figure 1), and its young shudder to maintain their body temperature. A previous study has shown that the temperature in such a den can be as high as 20o C in an outdoor temperature of -20o C. In modern pig production heat lamps are used to help the newborn piglets retain their body temperature (Figure 2).
The findings show that an important biological function can be lost if it is not vital to life during a period in the evolutionary history of a species, and that if the living conditions once again change, compensatory mechanisms can be developed. The lack of UCP1 and brown fat in the pig resembles the inability of humans to produce vitamin C, a feature we lost during our evolutionary history.
“The findings we present are fully consistent with the theory of evolution. An important trait can be lost if it is not absolutely necessary to life during the development of a species,” says Leif Andersson.
“At the time the study illustrates why the idea of intelligent design is such a poor explanatory model for the variation we find in nature. If a creator happened to make a mistake with the UCP1 gene in the pig, why four different mistakes when one would have been enough to disrupt gene function. And why was the same mistake made when the wart hog and other closely related species were created? It cannot possibly be a matter of intelligent design.”
Energy crop production on conservation lands may not boost greenhouse gases
13.03.2017 | Penn State
How nature creates forest diversity
07.03.2017 | International Institute for Applied Systems Analysis (IIASA)
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy