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Discovery of extra arm artery in modern humans suggests evolution has not stopped: study – CTV News

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TORONTO —
Researchers in Australia have discovered a physiological trend in the human body that suggests human evolution is not over.

The median artery is the main vessel that supplies blood to the human forearm and hand while in the womb, but typically disappears around the eighth week of gestation once two other arteries develop.

An investigation published in the Journal of Anatomy has found that an increasing number of adults have retained all three arteries. Scientists say this microevolutionary change in the anatomy of the human body is now present in 35 per cent of people. They predict that people born 80 years from now will all carry a median artery if the trend continues.

The presence of a median artery in an adult body was also studied back in 1995. Since then, researchers have found that it has been increasing over time from “approximately 10 per cent in people born in the mid 1880s to approximately 30 per cent by the end of the 20th century,” the study says.

Scientists say the median artery should be considered a “normal human structure” once it becomes prevalent in more than 50 per cent of adults.

“Since the 18th century, anatomists have been studying the prevalence of this artery in adults and our study shows it’s clearly increasing,” said researcher Teghan Lucas in a statement. “This increase could have resulted from mutations of genes involved in the median artery development or health problems in mothers during pregnancy, or both actually.”

She added, “ If this trend continues, a majority of people will have median artery of the forearm by 2100.”

Over the years, researchers have discovered a small number of anatomical changes of the human body, including the increased absence of wisdom teeth. Lucas suggests that modern humans are evolving at a faster rate than at any point in the past 250 years.

The study’s co-author, professor Maciej Hennenberg, says the median artery offers benefits because it can increase overall blood supply and can be used as a replacement in surgical procedures.

“This is microevolution in modern humans and the median artery is a perfect example of how we’re still evolving because people born more recently have a higher prevalence of this artery when compared to humans from previous generations,” Hennenberg said.

He added, “We’ve collected all the data published in anatomical literature and continued to dissect cadavers donated for studies in Adelaide and we found about one third of Australians have the median artery in their forearm and everyone will have it by the end of the century if this process continues.”

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B.C. Halloween forecast: Frightfully chilly under a spooky full moon – Vancouver Sun

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While the weather is expected to be frightfully cold in much of B.C. this Halloween, those who venture outdoors may be in for a treat.

A rare full “blue” moon is expected Saturday night, the second full moon this month.

The last time trick-or-treaters went out under a full moon in B.C. was in 2001, but the last Halloween full moon in all time zones was in 1944, according to the Farmer’s Almanac.

© Gideon Knight_Wildlife Photographer of the Year, Young Grand title young winner Featuring: The moon and the crow. Photo by CB2/ZOB /Gideon Knight/Wildlife Photograp

As for the weather, if you’re in Metro Vancouver it’s likely going to be clear and sunny during the day with a high of 11 C, and then partly cloudy at night with a low of 5 C, according to Environment and Climate Change Canada.

Elsewhere in B.C., the Prince George and Williams Lake areas should see a mix of sun and cloud with a high of around 4 or 5 C and an overnight low of 2 C, while in the Okanagan it will likely be overcast and 10 C, dipping down to 4 C overnight with a slight chance of showers.

In the northern region of Dease Lake, the forecast looks for sunny during the day and freezing at night, plunging to minus 7 C overnight.

In the central B.C. region, some communities may have snow Saturday. The agency is forecasting a good chance of flurries in Smithers during the day but showers overnight.

ticrawford@postmedia.com

More to come …

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Elusive and extremely rare catshark captured in amazing video – CNET

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This short-tail catshark (Parmaturus bigus), seen at the Great Barrier Reef off the coast of Australia, is a rare sight.


Schmidt Ocean video screenshot by Amanda Kooser/CNET

Great whites might be the jumbo stars of the shark world, but there are some equally fascinating members on the other side of the size spectrum. The crew of the research vessel Falkor experienced the wonders of the deep when it spotted “one of the rarest species of sharks in the world” during a recent Schmidt Ocean Institute mission.

Shark expert Will White with the Commonwealth Scientific and Industrial Research Organisation, Australia’s national science research agency, identified the short-tail catshark Parmaturus bigus from footage captured during an exploration of the Great Barrier Reef on Oct. 17. Falkor’s remotely operated submersible SuBastian got a good look at the big-eyed creature. 

Though you can chill out and enjoy the hours of underwater footage and scientific commentary, the shark appears a little over two hours into this video. “It’s a shark!” the scientists comment as they zoom in.

Researchers have collected only one specimen of Parmaturus bigus, which is held in the Australian National Fish Collection. The one spotted lounging on the sand was a male estimated to be around 20 inches (50 cm) long. The remotely operated vehicle was able to follow it as it swam off.

Even better, the ocean researchers discovered they had filmed another specimen during a dive back in May but hadn’t identified it at the time. The team also found footage of an egg case from the short-tail catshark, giving scientists a wealth of new information about the species and its habitat.

“Through the efforts of the Falkor team, we now have three more records of one of the world’s rarest sharks,” Schmidt Ocean said in a statement Monday, including “the first footage of a living specimen.”

Schmidt Ocean expeditions have gifted us some extraordinary views of the marvels of the deep in recent years, from a stunningly bizarre siphonophore to a wild “benthic tornado.” The catshark fits in beautifully with this impressive track record of discovery.

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'One of the rarest species of shark in the world' captured in amazing video – CNET

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This short-tail catshark (Parmaturus bigus), seen at the Great Barrier Reef off the coast of Australia, is a rare sight.


Schmidt Ocean video screenshot by Amanda Kooser/CNET

Great whites might be the jumbo stars of the shark world, but there are some equally fascinating members on the other side of the size spectrum. The crew of the research vessel Falkor experienced the wonders of the deep when it spotted “one of the rarest species of sharks in the world” during a recent Schmidt Ocean Institute mission.

Shark expert Will White with the Commonwealth Scientific and Industrial Research Organisation, Australia’s national science research agency, identified the short-tail catshark Parmaturus bigus from footage captured during an exploration of the Great Barrier Reef on Oct. 17. Falkor’s remotely operated submersible SuBastian got a good look at the big-eyed creature. 

Though you can chill out and enjoy the hours of underwater footage and scientific commentary, the shark appears a little over two hours into this video. “It’s a shark!” the scientists comment as they zoom in.

Researchers have collected only one specimen of Parmaturus bigus, which is held in the Australian National Fish Collection. The one spotted lounging on the sand was a male estimated to be around 20 inches (50 cm) long. The remotely operated vehicle was able to follow it as it swam off.

Even better, the ocean researchers discovered they had filmed another specimen during a dive back in May but hadn’t identified it at the time. The team also found footage of an egg case from the short-tail catshark, giving scientists a wealth of new information about the species and its habitat.

“Through the efforts of the Falkor team, we now have three more records of one of the world’s rarest sharks,” Schmidt Ocean said in a statement Monday, including “the first footage of a living specimen.”

Schmidt Ocean expeditions have gifted us some extraordinary views of the marvels of the deep in recent years, from a stunningly bizarre siphonophore to a wild “benthic tornado.” The catshark fits in beautifully with this impressive track record of discovery.

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