Chewing gum was already used by humans 10,000 years ago according to a study published in Communications Biology. Researchers from Uppsala University, Stockholm University and the Museum of Cultural History in Oslo analyzed the DNA in ancient chewing gum used by human tribes that settled in Scandinavia more than 10,000 years ago.
These gums were mostly composed of lumps made of birch bark and are thought to have been used as glue in the production of tools or other types of tools. It was precisely these lumps, chewed and then spit out by humans at the time, that provided a unique opportunity to analyse the DNA of these humans, DNA that is currently the oldest ever sequenced DNA belonging to humans from this area.
The DNA analyzed comes from three individuals, two females and a male, and was taken from chewed birch bark found near Huseby-Klev, an ancient site of Mesolithic hunters and fishermen on Sweden’s west coast. The excavation at this site began in the early 90s but only today, with today’s techniques, was it possible to analyze this ancient DNA.
The results show that these people share a genetic affinity with other hunter-gatherers who settled in the area of present-day Sweden and with the first populations from the Mesolithic period until the Ice Age.
“The DNA of these ancient chewing gums has enormous potential not only to trace the origin and movement of peoples long ago, but also to provide insights into their social relationships, diseases and food,” says Persson, a researcher at the Museum of Cultural History in Oslo.
Rising sea levels continue to be a cause for concern. Using new techniques to measure ice in the world’s polar regions, a group of experts has calculated that the seas on our planet could rise by two meters by 2100, an increase essentially due to the melting of the polar ice. This is an increase in sea level which would literally mean flooding coastal cities like New York.
The main author of this new study, Jonathan Bamber of the University of Bristol in the UK, clearly states that a sea-level rise of more than two meters cannot be ruled out if we continue along today’s trajectory of emissions, essentially those caused by the burning of fossil fuels, which cause global warming through increased CO2 in the atmosphere.
This trajectory predicts an increase of 5°C in the average global temperature, one of the worst scenarios, substantially the one that would occur if the situation were to remain as it is today and if no counteracting action were to be taken by world governments in the coming years.
Such an increase would lead to a loss of land of about 1,200,000 square miles, an area equivalent to three times that of California. Not only New York and Miami would be flooded, but also other cities such as London and Rio de Janeiro, situations that would involve almost 200 million people in the world who would then have to be moved elsewhere, with more than harmful consequences for humanity, especially from an economic point of view.
This assessment is twice as high as other assessments recently presented by other experts. And the study’s projections go even further even though uncertainty about the forecasts naturally increases exponentially. In the worst-case scenario, sea levels could rise by as much as 7.5 meters by 2200.
A group of researchers at Imperial College London used complicated genetics techniques to ensure that laboratory-grown chicken cells could successfully fight the avian influenza virus. This new step forward once again raises the fateful question of whether genetically modified chickens can be created, even for human consumption, to resist this widespread disease affecting birds.
At the moment no live chicken has been born with these genetic modifications but this could be the next step of the team of scientists. Specifically, the researchers, with the help of genetic experts from the Roslin Institute at the University of Edinburgh, have eliminated a particular section of DNA from chickens within cells of the same grown in the laboratory. This section of DNA is responsible for the creation of a particular molecule that is in turn exploited by the virus to spread.
The molecule targeted by British researchers, called ANP32A, is the one that is used by the avian influenza virus. The latter, in fact, hijacks this very molecule and attacks it in order to replicate faster. Once this section was eliminated, the virus was no longer able to grow inside the cells. This technique could be used to limit the spread of this disease, which is very serious for birds but can also take root, although rarely, in humans.
According to Mike McGrew, of the Roslin Institute, it is a “major advance that suggests that we may be able to use genetic modification techniques to produce chickens resistant to avian influenza. We haven’t yet produced birds and we need to see if DNA change has other effects on bird cells before we can take the next step.”
According to a new study published in The Journal of Physiology, exaggerating the diet with omega 6 fats, particularly linoleic acid, could be harmful during pregnancy. In particular, a diet with three times the recommended daily dose of linoleic acid could be particularly dangerous.
Linoleic acid, present in foods such as potato chips and vegetable oil, bring about several changes in liver function, as researchers themselves have seen when conducting experiments on pregnant female mice. The researchers fed several rats over the course of 10 weeks on a diet with a high level of linoleic acid.
They then matched these rats and studied pregnant female mice. The latter showed an altered liver, particularly in terms of inflammatory protein concentrations. The latter caused the uterus to contract during pregnancy and decreased levels of a particular hormone that regulates the growth and development of the fetus.
Such changes, according to the researchers, can lead to various complications during pregnancy, including poor development of the baby.
According to Deanne Skelly, one of the authors of the research, “It is important that pregnant women consider their diet and our research is another example that potentially consuming too much of a certain type of nutrient can have a negative impact on the growing child.”