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For decades scientists believed that monkeys could not speak human language due to an anatomical difference in vocal tracts. Today, we're not so sure that this is the limiting factor after all.

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Hank: Animal researchers have really tried to teach nonhuman primates to talk. They even raised baby chimpanzees in human homes, to expose them to speech just like human babies. But all these attempts have failed. Because of some influential studies a couple decades ago, most scientists have thought that the vocal anatomy of nonhuman primates was to blame.

But, according to a paper published in Science Advances this month, their brains might be the limiting factor. In the 1960s and 1970s, scientists studying rhesus macaques and chimpanzees used computer programs to figure out the range of sounds they should be able to make. They concluded that these primates’ throats and mouths just couldn’t produce all the sounds needed for a language like ours.

This supported the idea that modern humans evolved some special vocal anatomy that paved the way for language, rather than developing special brain mechanisms to coordinate already-advanced vocal tracts. But these critical 1969 computer models were based on plaster casts of the vocal tracts of dead rhesus macaques. Those scientists tried to shape the monkeys’ tongues and lips to approximate what a bark would look like, and then estimated the whole range of movement... which may or may not have captured the full flexibility of a live monkey.

Fast-forward to this year, with a team of international researchers who wanted to create an updated model. These researchers took X-ray videos of three living rhesus macaques while they were making a bunch of different facial expressions: like making noises, chewing, and swallowing. They digitally traced the outlines of the monkeys’ vocal tracts, and used those tracings – rather than estimated movements – to create a computer model of all the ways they could contort their mouths and throats. Some fancy math let them calculate the range of sounds the monkeys could theoretically make, using an English-speaking adult human female for comparison.

The scientists concluded that the macaques should be able to almost make most of the vowel sounds in American English. They even used their results to simulate what it would sound like if a macaque said “Will you marry me?” mixed with some noise. It’s... kind of terrifying. But the creepiness is besides the point. Also why they chose that particular phrase.

But the fact that these researchers were able to make this model flies in the face of decades of belief that nonhuman primates can’t talk because their throats can’t make the right sounds. Instead, their brains might be the limiting factor after all – even though the physical pieces are mostly in place, their neural circuitry just doesn’t give them the fine level of control they need to mimic human language.

While some scientists were studying the evolution of language, another group was learning about bacterial evolution. In a paper published in Nature Communications this month, some researchers analyzed a bacterium that has a scarily-good set of genes for antibiotic resistance. But here’s the catch: the microbe wasn’t found anywhere near human antibiotics. It’s been isolated deep beneath the Earth’s surface for four million years, in a New Mexico cave. So its fully-sequenced genome may give researchers a head start in tackling resistance in the germs that do make us sick.

Antibiotic-resistant bacteria are a huge threat to human health. Let’s say you’re sick and taking some antibiotics, which are designed to kill off nasty disease-causing bacteria. Antibiotics work in lots of different ways – some break down the walls of bacterial cells, some keep bacteria from making crucial proteins, and some stop bacteria from copying their DNA so they can’t reproduce. If just one bacterium in your system has a genetic variation that lets it survive these attacks, it can make a whole line of superbugs. That’s how natural selection works. But those antibiotic resistance genes – which scientists collectively call the resistome – have to come from somewhere. Sometimes they come from random mutations, but these genes can actually be pretty common in the genomes of all sorts of bacteria, even the ones that don’t cause disease.

See, a lot of our antibiotics started out as weapons that different microbes used against each other. So this means that bacteria that have no interest in humans might still be resistant to our antibiotics. Take the microbes from a thousand feet underground in New Mexico’s Lechuguilla Cave, which have been living in isolation from the rest of life on Earth for millions of years. These cave-dwellers don’t pose any sort of danger to humans, but they have shown resistance to almost all known antibiotics, including some of our most powerful drugs.

One bacterium, known as Paenibacillus sp. LC231, was resistant to 26 of the 40 antibiotics tested on it, and shares lots of resistance mechanisms with its surface-dwelling cousins. But it also has five new mechanisms for resistance – genes that let the bacterium slice up, rearrange, and ignore antibiotic molecules in ways we haven’t seen before. That sounds kind of scary, but it actually gives scientists a head start to try and combat these resistance pathways, before they become a possible problem for human health. Just because pathogens haven’t evolved them yet doesn’t mean they won’t in the future.

Thanks for watching this episode of SciShow News, and if you want to see us live and in person, we will be at Nerdcon: Nerdfighteria in Boston on February 25th and 26th check out to learn more, there is a link in the description, and we hope to see you there.