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Tiny primate ‘talks’ in ultrasound

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One of the world’s smallest primates, the Philippine tarsier, communicates in a range of ultrasound inaudible to predator and prey alike, according to a study published Wednesday.

No bigger than a man’s hand, Tarsius syrichta can hear and emit sounds at a frequency that effectively gives it a private channel for issuing warnings or ferreting out crickets for a nighttime snack, the study found.

Only a handful of mammals are known to be able to send and receive vocal signals in the ultrasound range, above 20 kilohertz (kHz), including some whales, domestic cats and a few of the many species of bats.

And few of these can squeal, screech or squawk at the same sonic altitudes as the saucer-eyed tarsier, which up to now had been mistakenly described as being “ordinarily silent,” researchers found.

Its finely-tuned ears are capable of picking up frequencies above 90 kHz, and it can vocalise in a range around 70 kHz.

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By comparison, humans generally can’t hear anything above 20 kHz, and a dog whistle is pitched to between 22 and 23 kHz.

A team of scientists from the United States and the Philippines led by Marissa Ramsier of Humboldt State University in California gathered their inaudible results in two ways.

First they captured six of the docile nocturnal creatures and placed them inside custom-build sound chambers to test their sensitivity to high-pitched sounds.

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After the experiments, the rare and endangered animals were returned unharmed to their natural habitat, on the Philippine island of Mindanao.

To measure the frequency of the tarsier’s ultrasound chatter, the researchers recorded another 35 specimens in the wild.

“The minimum frequency of the call — 67 kHz — is the highest value of any terrestrial mammal, excluding bats and some rodents,” said the study, published in the British Royal Society’s Biology Letters.

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What advantages do the tarsier’s high-end vocal acrobatics confer? There are several, the researchers suggest.

One is being able to sound a silent alarm.

“Ultrasonic calls can be advantageous to both the signaller and receiver as they are potentially difficult for predators to detect and localise,” the researchers explain.

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The tarsier’s exceptional hearing may also facilitate acoustic eavesdropping on noises emitted by prey, which range from crickets and cockroaches — their staple diet — to the occasional moth, katydid or hatchling bird.

Finally, the study speculates, being able to communicate in ultrasonic ranges filters out all the low-frequency “noise” and hubbub of a tropical environment.

Tarsier’s have five-digit hands that eerily resemble — in emaciated form — their human counterparts.

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Lacking the typical “night vision” of other nocturnal creatures, they also have — in relation to their body size — the largest eyes of any primate on Earth.


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American, Italian and Russian blast off for ISS

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US, Italian and Russian astronauts blasted into space Saturday, headed for the International Space Station, in a launch coinciding with the 50th anniversary of the Apollo 11 Moon landing.

Alexander Skvortsov of the Russian space agency Roscosmos, NASA's Andrew Morgan and Luca Parmitano of the European Space Agency set off on a six-hour journey to the orbiting science lab from the Baikonur Cosmodrome in Kazakhstan at 1628 GMT.

A NASA TV commentator hailed a "textbook launch" minutes after blastoff in "sweltering" weather in Baikonur, where daytime temperatures reached 43 degrees Celsius on Saturday.

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Megan Rapinoe trashes ‘disgusting’ Trump for his ugly racist tweets in CNN interview

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In an interview with CNN's Van Jones that will air on Saturday night, U.S. Women's soccer champion Megan Rapinoe condemned President Donald Trump's racist attacks on four progressive congresswomen of color.

"It's disgusting, to be honest. To say it's disappointing is ... it doesn't even come close," said Rapinoe. She added, "The more that we just are upset about it and don't accept that kind of behavior from all sides, then the better place we're going to be."

Trump has faced escalating criticism in the wake of his tweet that Reps. Alexandria Ocasio-Cortez (D-NY), Rashida Tlaib (D-MI), Ilhan Omar (D-MN), and Ayanna Pressley (D-MA) ought to "go back" to where they came from if they disagree with his agenda (three of them were born in the United States). The controversy escalated when attendees of his rally in Greenville, North Carolina chanted "Send her back!" about Omar.

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Conservative suggests Trump’s racist rhetoric will incite worse than ‘send her back’ chants: ‘One shudders to wonder’

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In a column for the Washington Post, conservative Pulitzer Prize-winning writer Kathleen Parker said the refusal by Republican lawmakers and the evangelical community to condemn Donald Trump's racist rhetoric is paving the way for something far worse than mere "send her back" chants.

Under a headline that bluntly states, "Those who don’t condemn Trump’s racism are complicit in his bigotry," Parker gets right to her opinion of the president, writing, "Going out on a limb here: President Trump is a racist. And a sexist. And a xenophobic nationalist. Among other things. Not to name call or anything."

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