New Delhi: A first-of-its-kind study has used an unusual metric to test environmental pollution across regions—honey.
Bees encounter a number of environmental factors like water, air and soil of a region when collecting honey. Now, American scientists have tested 260 samples of local honey across 48 US states to find varying traces of arsenic, lead, cadmium, nickel and other metal pollutants. The study will appear in the Environment Pollution journal’s January edition.
The scientists found that while none of the honey samples had pollutant levels above the safety limit, they did differ in terms of regions. For instance, in northwestern regions, they found honey with high arsenic content, which the scientists speculate could be because of historically high pesticide use. Meanwhile, high lead concentrations in honey from North and South Carolina could be because they are mining regions.
The study could elevate the use of honey as a metric for understanding local environmental pollution and its sources. Read more.
Early humans in America ate mammoths as part of regular diet
As part of a new study that uses isotope analysis, Canadian researchers have been able to determine the diet of a group of early Americans called Clovis people. A paper in the journal Science Advances published Wednesday finds that mammoths—ancestors of modern elephants that went extinct about 4,000 years ago—were a big part of the diet of the early Americans that lived more than 10,000 years ago.
Isotope analysis is a type of study in which scientists look at the presence and composition of stable isotopes of carbon and nitrogen in the remains of ancient humans, and then compare it with available food sources nearby. The similarities in isotope structures of the human and food remains allow them to infer what the human’s diet was composed of. In the case of Clovis people, the scientists analysed isotopes found on a specimen named Anzick-1, which was the first Clovis child to be fully genome-sequenced and whose data was readily available.
They found that not just mammoths, but even bison and camels were part of the Palaeoindians’ diet, along with other protein sources such as elk. What this shows is that the Clovis people were regularly used to hunting large prey like mammoths, also called megafauna. Read more.
Stem cell therapy to cure blindness in pigs
A new study explores the use of stem cell therapy to cure blindness. Scientists at the University of Montreal have used human stem cells to create retinal sheets and transplanted them into mini pigs with retinal blindness.
These sheets helped regenerate retinal tissues, including cone receptors that aid in seeing shapes and colours. They used mini pigs because the shape of their eyes is very similar to that of humans, and the scientists actually found that stem cell therapy helped in restoring the vision of mini pigs suffering from retinal degenerative disease. While the technology is not ready to be used on humans yet, it is a step forward in stem cell therapy for blindness. Read more.
How giant elliptical galaxies formed
An intercontinental collaboration has helped solve an intergalactic mystery. There are currently huge elliptical or spheroid galaxies with billions to trillions of stars in them. They are not flat disc-shaped like our Milky Way; rather have a central dense region that hosts several stars. But their formation has been a mystery to astronomers worldwide.
Now, in a new Nature study published Wednesday, a group of global scientists argue that these elliptical galaxies came into existence because of two flat disc galaxies merging, releasing tonnes of gas which then led to star formation at massive scales. The scientists used the world’s largest radio telescope—the Atacama Large Millimeter Array—to study the light signals coming from early universe galaxies which are famous for their rapid star formation.
For context, the rate at which these galaxies form stars is at least 10-100 times faster than that of the Milky Way. Scientists finally have an explanation for the spheroid galaxies’ shape and origin, which could facilitate further research. Read more.
(Edited by Radifah Kabir)
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