Moon formation: Was it a 'hit and run' accident?

Computer simulations suggest a large, fast-moving body impacted the Earth to create the Moon  Scientists have proposed a fresh idea that in the process of Moon formation the crash happened with a much larger, faster body than previously thought. What is certain is that some sort of impact from another body freed material from the young Earth and the resulting debris coalesced into today's Moon. But the exact details of the impactor's size and speed have remained debatable. The report will be published online in Icarus. Such theories need to line up with what we know about the Moon, about the violent processes that set off the creation of moons, and what computer simulations show about the more sedate gravitational "gathering-up" that finishes the job. In recent years, scientists' best guess for how the Moon formed has been that a relatively slowly moving, Mars-sized body called Theia crashed into the very young Earth. That would have heated both of them up and released a vast cloud of molten material, much of which cooled and clumped together to give rise to the Moon. That would suggest that the Moon is made up of material from both the early Earth and from Theia, which should be somewhat different from one another. What complicates that story is a number of observations of...

Read More........→July 30, 2012

Honk! These monkeys have truly legendary noses – now we better understand why they evolved

Slavianin/Shutterstock Katharine Balolia, Australian National University Of all the monkey species around the world, one stands out with its large, bizarre nose. In male proboscis monkeys, their bulbous noses will often hang past their mouths. But why evolve such a strange feature? Are they a visual sign of health and status to potential female mates, and to other males? Or did they evolve to help the monkeys make honks and other loud sounds? In our new study, published in Scientific Reports, we have deepened our understanding of these enlarged nasal structures by investigating what lies beneath: the structures in the skull. Our findings help to explain how these noses function as visual and acoustic signals of health and status. They also add to a growing body of evidence that shows researchers can use close examinations of skulls to glean information about primate social behaviour. A battle of noses One of the largest monkey species in Asia, proboscis monkeys (Nasalis larvatus) are endemic to the island of Borneo. They live in coastal mangroves, peat swamps and riverine forests, and have an unusual diet made up mostly of leaves. They can swim quite well and have webbed fingers and toes. They typically live in harem groups, made up of a single adult male (who tends to have a large, bulbous nose), some adult females...

Read More........→May 31, 2024