Science News

Western Australian rock art could represent chaos that followed at the end of the ice age

The examples of rock art from Gwion in Western Australia, discovered in 1891, may date back 10,000-12,000 years according to a team of archaeologists. The researchers used an unusual dating method: they dated the tiny grains of coal in the fossilized wasp nests created by these insects on the painted walls.

Dating rock art is always difficult since the substances that are used to paint, mostly ocher minerals, cannot be dated to radiocarbon. The researchers, therefore, thought of using the nests made by the so-called “mud wasps,” flying insects that build their nests from the mud, in this case on a rock substrate.

The researchers measured how long the grains of quartz sand that wasps from the past used to create their nests were present on the rock where the paintings were. These are nesting wasps whose nests, made of mud, petrify after abandonment. These remains can be analyzed through various complex optical techniques and it is also possible to date the traces of pollen contained in them. With this method, they established that Gwion’s rock art examples date back over 10,000 years ago.

It is a period that coincides with the end of an ice age, a period during which the level of the oceans rose and there were floods in northern Australia.

This led the Aboriginal people who lived near the coasts to take refuge inland and precisely these forced emigrations could be the object of the meaning of many drawings that often depict human figures moving with bags and headdresses.

Science News

Here’s how pollution from coal-fired power plants can clog lungs

A new experiment conducted by a professor at the Virginia-Maryland College of Veterinary Medicine confirms that burning coal can cause serious lung damage. Specifically, the researchers conducted experiments on mice by exposing them to ashes or fumes of burnt coal.

Irving Coy Allen, along with colleagues from various other American institutes and a university in Shanghai, has discovered that very small titanium oxide particles can prove highly toxic. These particles would be present in the ash and smoke of burnt coal. Lung damage to mice also occurred after a single exposure while long-term damage occurred in just six weeks of exposure.

Current coal-fired plants have very complex filters to avoid most of the emissions of nanoparticles into the atmosphere following the combustion of coal. However, when these filters are not present or not efficient, these particles can expand into the air and easily enter the lungs.

Especially the smallest particles, known as titanium suboxide nanoparticles, are of most concern to scientists. These are very small particles, which reach a diameter of 100 millionths of a meter. Once they enter the lungs, they come across macrophages, the defensive cells that are supposed to counteract foreign particles.

Against these particles, so small, macrophages go into difficulty. They cannot decompose them and begin to die, a process leading to increased recruitment of macrophages.

It is a “surprising discovery,” as Allen himself defines it, and a phenomenon that occurs after only one exposure. And even after long periods of time, these buildups remain in the lungs. This phenomenon, of course, raises concerns about urban pollution produced by coal-fired power plants.

Science News

Discrimination of children and adolescents linked to their mothers poor health

When a child suffers discrimination, the mother can suffer harm not only on a psychological level but also on a health level. Indeed, a new study analyzes the link that exists between unfair social treatment by young adults and the decline in the health of their mothers during middle age.

“Our study suggests that when a child experiences discrimination, these cases of unfair treatment are likely to harm the health of the mother as well as their own,” says Cynthia Colen, a sociology professor at Ohio State University and lead author.

This is the first study that finds a link in the “opposite” direction between discrimination and unfair treatment of children and young people and the health of their mothers. Previously, links had been found between unfair treatment of pregnant women and the health of their children.

To carry out the study, the results of which were published in the Journal of Health and Social Behavior, the researchers analyzed two generations of families using data from a survey started in 1979 that followed the subjects for more than forty years. The database consisted of data concerning 3,004 mothers and 6,562 children.

Discrimination levels and unfair treatment were assessed through responses to specific surveys while mothers’ health was self-assessed. All mothers were between 40 and 50 years old. The researchers also discovered racial disparities in the results: African American adolescents and young adults reported most of the experiences of discrimination and 31% of black mothers reported having poor health compared to 17% of white mothers and 26% of mothers Hispanic.

“We now know that these negative health effects are not limited to the person experiencing firsthand discrimination – instead they are intergenerational and will likely contribute to racial health disparities which means that black people can expect to die younger and live a lesser life,” reports Colen.