Viruses -- lots of them -- are falling from the sky

An astonishing number of viruses are circulating around the Earth's atmosphere -- and falling from it -- according to new research from scientists. according to Science Daily.

The study marks the first time scientists have quantified the viruses being swept up from the Earth's surface into the free troposphere, that layer of atmosphere beyond Earth's weather systems but below the stratosphere. The viruses can be carried thousands of kilometres there before being deposited back onto the Earth's surface.

Moon's slow retreat from frozen Earth

A study led by researchers provides new insight into the Moon's excessive equatorial bulge, a feature that solidified in place over four billion years ago as the Moon gradually distanced itself from the Earth according to Science daily.

The research sets parameters on how quickly the Moon could have receded from the Earth and suggests that the nascent planet's hydrosphere was either non-existent or still frozen at the time, indirectly supporting the theory of a fainter, weaker Sun that at the time radiated around 30 percent less energy than it does today.

"The Moon's fossil bulge may contain secrets of Earth's early evolution that were not recorded anywhere else," said Shijie Zhong, a professor and the co-lead author of the new research. "Our model captures two time-dependent processes and this is the first time that anyone has been able to put timescale constraints on early lunar recession."

Scientists discover how giardia parasite makes you ill

It is a stomach bug known to afflict some backpackers with bouts of uncomfortable diarrhoea.

Now scientists say they have discovered how the parasites that cause giardiasis - one of the world's most common gastric diseases - make people ill, according to BBC.

Giardia parasites mimic human cell functions to break apart cells in the gut and feed inside, researchers found.

This also allows bacteria already present in the body to join in and feed from the same nutrients, they said.

Brain systems responsible for our ability to learn language

The origins of humans' ability to learn language may be older than our species itself.

New research has found that language may be learned in ancient 'general purpose' brain circuits that emerged before humans existed, and can even be found in other animals, according to Daily Mail.

It’s long been thought that human language relied solely on mechanisms found in our species – but, the new findings now suggest this may not be the case, after all.

In addition to the evolutionary implications, experts say the discovery could be used to help improve language learning for those who may have difficulties, including people with dyslexia and stroke-related damage. 

Researchers analyzed the findings of 16 studies that examined language learning in two systems in the brain: declarative and procedural memory.

The modern human brain may be younger than previously thought

The earliest-known specimen of a Homo sapiens dates back to roughly 300,000 years ago, according to Daily Mail. 

Though much has changed since then, scientists long believed that our species still retained one common feature - our brains.

It turns out that our brains actually look much different from our ancestors that lived hundreds of thousands of years ago.