Human evolution, alcohol and chemistry


This video is called African Animals Getting Drunk From Ripe Marula Fruit.

By Bob Yirka today:

Study shows pre-human ancestors adapted to metabolize ethanol long before humans learned about fermentation

19 hours ago

(Phys.org)—A team of researchers in the U.S. has found evidence to support the notion that our pre-human ancestors were able to metabolize ethanol long before our later ancestors learned to take advantage of fermentation—to create alcoholic beverages. In their paper published in Proceedings of the National Academy of Sciences, the team describes how they genetically sequenced proteins from modern primates and used what they found to work backwards to discover just how long ago our ancestors have been able to metabolize ethanol.

Humans have been consuming beverages that make them tipsy, drunk and/or sick for a very long time, of that there is little doubt. But why do we have the ability to metabolize ethanol in the first place? That’s what the team set out to answer. They began by sequencing an enzyme called ADH4—it’s what’s responsible for allowing us to metabolize ethanol. Other have it as well, but not all metabolize ethanol as well as we do. By sequencing ADH4 found in a 28 including 17 that were primates, the team was able to create a family tree of sorts based on ethanol metabolizing ability. The team then tested those sequences for their metabolizing ability by synthesizing nine kinds of the ADH4 enzyme. Doing so showed the researchers that most early primates had very little ability to metabolize ethanol for most of their early history.

Then, about 10 million years ago, some of the ancestors of modern humans suddenly were able to do a much better job of it, while others that diverged and led to apes such as orangutans, did not. This discovery led the team to wonder what might have occurred to cause this to come about. They note that other evidence has shown that around this same time, the planet cooled slightly, making life a little more difficult for our tree dwelling ancestors. They suggest they began climbing down out of the trees to eat the fruit that fell, which gave them a food advantage and a reason for developing the ability to metabolize —otherwise they would have become too drunk from eating the fermenting fruit to defend themselves or live otherwise normal lives. If true, the theory would also offer a major clue as to why our became terrestrial.

Explore further: Study unlocks secret of how fruit flies choose fruit with just the right amount of ethanol

More information: Hominids adapted to metabolize ethanol long before human-directed fermentation, PNAS, Matthew A. Carrigan, DOI: 10.1073/pnas.1404167111

Abstract

Paleogenetics is an emerging field that resurrects ancestral proteins from now-extinct organisms to test, in the laboratory, models of protein function based on natural history and Darwinian evolution. Here, we resurrect digestive alcohol dehydrogenases (ADH4) from our primate ancestors to explore the history of primate–ethanol interactions. The evolving catalytic properties of these resurrected enzymes show that our ape ancestors gained a digestive dehydrogenase enzyme capable of metabolizing ethanol near the time that they began using the forest floor, about 10 million y ago. The ADH4 enzyme in our more ancient and arboreal ancestors did not efficiently oxidize ethanol. This change suggests that exposure to dietary sources of ethanol increased in hominids during the early stages of our adaptation to a terrestrial lifestyle. Because fruit collected from the forest floor is expected to contain higher concentrations of fermenting yeast and ethanol than similar fruits hanging on trees, this transition may also be the first time our ancestors were exposed to (and adapted to) substantial amounts of dietary ethanol.

African 20th century liberation movements, film review


This video says about itself:

Concerning Violence – Official Trailer

A film by Goran Hugo Olsson, 2014, Sweden/U.S.A./Denmark/Finland.

By John Green in Britain:

Friday 28th November 2014

Gordon Hugo Olsson’s film on the anti-imperialist liberation movements globally in the ’60s and ’70s fails to connect with contemporary concerns, says JOHN GREEN

Concerning Violence (15)

Directed by Goran Hugo Olsson

3/5

DURING the cold war, radical Swedish filmmakers set out to capture footage from the anti-imperialist liberation movements in Africa first hand.

With their 16mm footage he discovered in the Swedish Television archives, Goran Hugo Olsson draws on his experience in Concerning Violence to create a visual narrative of the continent.

He bases his documentary on the ideas of Frantz Fanon and his explosive book about colonialism The Wretched of the Earth, written over 50 years ago.

While Fanon’s ideas at the time were iconoclastic and became immensely influential among liberation movements worldwide, this film — despite the best of intentions — hardly does them justice.

It begins ominously with a long and monotonously spoken introduction by academic Gayatri Chakravorty Spivak from Columbia University, who reads from a script.

If you haven’t already nodded off, a series of clips follows using unique archival footage from the archives. They include a night-time raid with the MPLA in Angola, interviews with Frelimo guerilla fighters in Mozambique, as well as with Thomas Sankara, Amilcar Cabral and other African revolutionaries.

These are contrasted with self-revealing interviews with dyed–in-the-wool colonialists including General Spinola, former Portuguese colonial warrior and later short-term president of Portugal.

While we well know that colonial attitudes and the horrific exploitation of Africa still continue today and that imperial countries are still waging brutal wars against struggling nations, the assembled footage feels ancient and no longer really relevant to the present.

Between clips of those anti-colonial struggles we are presented with large text bullet points or slogans taken from Fanon’s book, also read out like a Power Point presentation for dummies.

The filmmakers argue that Fanon’s work is still a major tool for understanding and illuminating the neo-colonialism happening now as well as the violence and reactions against it, but that claim is very open to question.

While it is salutary to be reminded of those anti-colonial struggles during the late 1960s and ’70s — and the sacrifices involved that gave the world so much hope and inspiration — it is also sobering to realise what became of them, demonstrating that a struggle is never finished. That’s something I’m sure Fanon would have agreed with.

Rare African desert warbler in western Europe for first time


This video is about an African desert warbler.

The video was recorded in Alphen aan den Rijn, the Netherlands, on 21 November 2014, by Adri de Groot.

This north African species had never been seen in Europe, except for a few times in Spain and Italy.

Photos of this bird are here. And here.

This is another video about that desert warbler.

See also here. And here.

Save a rhino, clip your fingernails


In this video, Marjo Hoedemaker (founder of the Marjo Hoedemaker Elephant Foundation) from the Netherlands speaks in Amersfoort zoo.

He says that in Vietnam and other countries, some people believe that rhino horn can cure cancer. This leads to poachers killing rhinos.

This quackery is nonsense. Rhino horn is the same stuff as human fingernails and toenails: keratin.

Marjo Hoedemaker proposes that people bring their clipped fingernails to Amersfoort zoo, starting on 1 December. A bin to collect the nails will then be next to the zoo’s rhino enclosure. As soon as Marjo will have five kilogram of keratin, he intends to bring it to the embassy of Vietnam in the Netherlands. The embassy may then send it to believers in Vietnam in the healing powers of rhino horn; thus saving rhino’s lives.

A pedicurist and other people have already said they will help.