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Fossil shrimp with five eyes could be elusive ‘transitional species’ – Haaretz

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We’re so egotistical about our morphology that we even portray alien beings from distant galaxies as looking like us, but green. Two eyes, two ears, a proboscis, etcetera. So first of all we apparently have a vestigial third eye in our brains and secondly, the world keeps showing us alternatives. On Wednesday, scientists at the Chinese Academy of Sciences disproved our conservatism yet again with a report on a strange sort-of-shrimplike ancestral creature that lived around half a billion years ago and had five eyes.

Kylinxia zhangi, named for a chimera in Chinese mythology named Kylin and the Chinese word for shrimp, was an arthropod. The main oddity of this early Cambrian proto-shrimp is actually that it combined features we know from other arthropods. Perhaps, Diying Huang and colleagues suggest in Nature, the lovely Kylinxia was a “transitional species.”

The fossil of Kylinxia zhangiCredit: D.-Y. Huang & H. Zeng

In other words, along the evolutionary road it appears to be a chimera of arthropod groups that would take shape in its future. Does that mean Kylinxia was ancestral to today’s arthropods? Not necessarily, but it may have been.

Transitional fossils, an animal on the cusp of divergence, are a holy grail to evolutionary biologists. Charles Darwin was embarrassed by the failure to identify fossils as transitional, ostensibly weakening his theory of evolution (published in 1859), blaming the absence on the spotty fossil record. Happily for his sanity, the transitional dinobird Archaeopteryx was discovered in 1861 – a transitional animal between non-avian and avian dinosaurs.

Now Huang and the team believe they have found a transitioning arthropod that has five compound eyes on stalks, like Opabinia; two large frontal claws like Anomalocaris (whose name means “unlike other shrimp”); and a basic body structure like the class Megacheira. Its head shield is fused like deuteropods. Its mouth is similar to that of the ancestral scorpion, the Chelicerata, and its feelers are reminiscent of the mandibulate arthropods, which includes everybody from millipedes to insects.

Opabinia regalis
Opabinia regalisCredit: Nobu Tamura / http://spinops.blo
Anomalocaris
Anomalocaris.Credit: PaleoEquii

Those frontal claws were orientated upward, by the way, and were spiny. Its tail fan was shrimplike, with three lobes. In today’s arthropods these tail lobes, called uropods, may be modified to serve as claspers to hold onto the female during mating. We cannot know what Kylinxia got up to with its uropods.

Summing up, Kylinxia seems like a transitional animal between the Radiodonta (stem-group arthropods, including some absolute monsters) and their cousins the Deuteropoda (which sport appendages on the second head segment), the team writes. It features characteristics of both: that fused head shield and “arthropodized” torso are pure deuteropodic, while the five eyes scream of radiodont.

Your third eye, by the way, evolved into your pineal gland, to somewhat oversimplify matters. The relic lizard called tuatara still has a relatively developed third eye on the top of its head. That third eye usually scales over in the reptile’s adulthood.

Artist's impression of Kylinxia zhangi
Artist’s impression of Kylinxia zhangi.Credit: D.-Y. Huang & H. Zeng
Megacheirans
Megacheirans.Credit: Junnn11

So there we have it. Does having five compound eyes mean it saw well? Half a billion years after the event, it’s hard to say. We can say that some extant shrimp see exceptionally well. The Mantis shrimp have extraordinarily advanced eyes: capable of seeing colors, ultraviolet light, polarized light and even circularly polarized light. You can’t do that. And they can move each of their (two) eyes independently. They also pack a punch that would put Rambo to shame. Shame that they can see you coming but still don’t get out of the way.

Here’s a video by Ze Frank about the mantis shrimp. Enjoy.

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China completes lunar sample collection ahead of schedule – CANOE

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BEIJING — China’s Chang’e-5 lunar vehicle has finished collecting samples of lunar rocks and soil more than a day ahead of schedule in the first lunar sample retrieval mission since the 1970s, the country’s space agency said on Thursday.

The robotic vehicle has stored the samples and will now dock with the orbiting Chang’e-5 for the return journey to Earth.

China launched a robotic spacecraft on Nov. 24 to bring back rocks from the moon in the first bid by any country to retrieve samples since 1976.

Late on Tuesday, the Chang’e-5 spacecraft successfully deployed a pair of landing and ascending vehicles onto the moon’s surface. The plan was to collect 2 kg (4.4 pounds) of samples.

The sample collection was completed after 19 hours, the space agency said in its statement, without disclosing the total weight of the samples collected.

China had planned to collect the samples over a period of about two days, with the entire mission taking around 23 days.

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The ascending vehicle would lift off from the lunar surface with the samples, and dock with a module currently orbiting around the moon.

The samples would then be transferred to a return capsule onboard the orbiting module for delivery back to Earth.

If successful, the mission will make China only the third country to have retrieved lunar samples after the United States and the Soviet Union.

China made its first lunar landing in 2013.

In January 2019, the Chang’e-4 probe landed on the far side of the moon, the first space probe from any nation to do so.

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Chinese lunar probe on way back to Earth – FRANCE 24

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Issued on: 03/12/2020 – 17:54Modified: 03/12/2020 – 17:52

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Beijing (AFP)

A Chinese space probe left the surface of the Moon Thursday to return to Earth, an ambitious effort to bring back the world’s first lunar samples in four decades.

China has poured billions into its military-run space programme, with hopes of having a crewed space station by 2022 and eventually sending humans to the Moon.

The Chang’e-5 spacecraft, named after the mythical Chinese Moon goddess, left the Moon at 11:10 pm (1510 GMT), said state broadcaster CCTV as mission engineers who were riveted to control screens applauded at length.

A module carrying lunar rocks and soil was in orbit after activating a powerful thrust engine, the China National Space Administration said of the mission that was launched from China’s southern Hainan province.

Scientists hope the samples will help them learn about the Moon’s origins, formation and volcanic activity on its surface.

If the return journey is successful, China will be only the third country to have retrieved samples from the Moon, following the United States and the Soviet Union in the 1960s and 1970s.

This is the first such attempt since the Soviet Union’s Luna 24 mission in 1976.

The spacecraft was due to collect two kilograms (4.5 pounds) of material in a previously unexplored area known as Oceanus Procellarum — or “Ocean of Storms” — a vast lava plain, according to the science journal Nature.

The samples will be returned to Earth in a capsule programmed to land in northern China’s Inner Mongolia region, according to US space agency NASA.

Under President Xi Jinping, plans for China’s “space dream”, as he calls it, have been put into overdrive.

Beijing is looking to finally catch up with the US and Russia after years of belatedly matching their space milestones.

China launched its first satellite in 1970, while human spaceflight took decades longer — with Yang Liwei becoming China’s first “taikonaut” in 2003.

A Chinese lunar rover landed on the far side of the Moon in January 2019 in a global first that boosted Beijing’s aspirations to become a space superpower.

The latest probe is among a slew of ambitious targets, which include creating a powerful rocket capable of delivering payloads heavier than those NASA and private rocket firm SpaceX can handle, a lunar base, and a permanently crewed space station.

China’s taikonauts and scientists have also talked up crewed missions to Mars.

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Midday fireball, boom thrill gazers from Ontario to Virginia – airdrietoday.com

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SYRACUSE, N.Y. — A noontime boom that was heard and felt from southern Ontario to Virginia was likely caused by a disintegrating meteor, according to an organization in western New York that keeps track of such phenomena.

Witnesses across the area reported hearing the boom or seeing a fireball in the sky shortly after noon on Wednesday, said Robert Lunsford of the American Meteor Society in Geneseo. By 5 p.m., the organization had recorded 90 reports of the fireball seen in Maryland, Michigan, New York, Ontario, Pennsylvania and Virginia.

Police agencies and fire departments around central New York received 911 calls reporting a boom that shook windows, but clouds prevented sightings in much of the area. Since most reports of the boom were around Syracuse, that’s likely where the meteor blew to bits, Lunsford said.

On the society’s website, an observer in western New York reported the fireball was bright white with shades of yellow. An observer in Hagerstown, Maryland reported a fireball with red and orange sparks, smoke and a persistent train. A report from Welland, Ontario, described a long, bright green train.

“Sunny day so it looked like a gold metallic flash against the blue sky,” said a report from Winchester, Virginia.

“Astonishing, amazing, still get goosebumps talking about it,” wrote an observer in Port Dover, Ontario. “The train was flaming white, wide and long, no smoke.”

“We tend to notice fireballs more at night because they stand out better, but it’s not terribly unusual for very bright ones to be noticed during the day. It happens several times a year over populated areas,” said Margaret Campbell-Brown, a member of the Meteor Physics Group at Western University in London, Ontario.

All fireballs, which are bright meteors, produce sound waves, sometimes detectable only by sensitive microphones, Campbell-Brown said by email. A large one may produce a thunderlike sonic boom with possible extra bangs from fragmentation, she said.

The Associated Press

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