Monthly Archives: January 2017

“Break In Search Of Origin Of Complex Life” By Ed Yong

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In Norse mythology, humans and our world were created by a pantheon of gods who lived in the realm of Asgard. As it turns out, these stories have a grain of truth to them.

Thanks to a team of scientists led by Thijs Ettema, Asgard is now also the name of a large clan of microbes. Its members, which are named after Norse gods like Odin, Thor, Loki, and Heimdall, are found all over the world. Many of them are rare and no one has actually seen them under a microscope. But thanks to their DNA, we know they exist. And we know that they are singularly important to us, because they may well be the group from which we evolved.

If Ettema is right, then around two billion years ago, an Asgardian microbe (or an incredibly close relative) took part in a unique event that gave rise to the eukaryotes. That’s the group which includes humans, our fellow animals, plants, fungi, and every living thing made from large, complex cells—all the living things we’re most familiar with, and all the ones we can actually see. Our origins lie either in Asgard, or next door to it.

To understand this story, we have to go back to the very beginning. The Earth was created around 4.5 billion years ago, and judging by some astonishingly ancient fossils, life emerged relatively soon after. For the longest time, living things belonged to two great domains: the bacteria and the archaea, both microscopic and both comprising single cells. That was the status quo for at least 1.7 billion years, until the two domains were joined by a third: the eukaryotes. And they were very different.

Eukaryotic cells are generally much bigger than either bacteria or archaea. They also have larger genomes. They have internal compartments that act like our organs, each with its own special job. They have an internal skeleton that acts as a transport network for molecules. There’s this huge gulf of complexity that separates them from the other two domains. It’s a gulf that has only ever been crossed once in life’s history. Bacteria and archaea are capable of amazing feats of evolution, but in over 3.7 billion years of existence, none of them have ever evolved into anything approaching a eukaryote-like cell—except that one time. Why?

One possible answer, which I’ve written about before, says that eukaryotes were created through an incredibly unlikely merger between members of the other two domains. Somehow, a bacterium found its way inside an archaeon and, rather than being digested or destroyed, became a permanent part of its host. In doing so, it provided the archaeon with an extra source of energy, which allowed it to get bigger, accumulate more genes, and evolve down new paths that were previously inaccessible to it. That fusion cell gave rise to the eukaryotes, and the bacterium eventually turned into the mitochondria—little bean-shaped structures that still power eukaryotic cells to this day.

Once the eukaryotes evolved, they repeatedly engulf microbes and fused with them—a process called endosymbiosis. But that’s much easier to do when the host cell is already big, and can engulf smaller neighbors. If the host is an archaeon, the feat becomes much harder and far more improbable. That’s maybe why the merger between an archaeon and a bacterium—the one that gave rise to mitochondria and may have spawned the eukaryotes—has only happened once.

What were those two ancient partners like? We know that the bacterium belonged to a group called the alphaproteobacteria (which also includes Wolbachia, a microbe that I’ve repeatedly written about here.) But until recently, no one knew anything about the archaeon host.

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5 REASONS KIDNAPPING OF PAKISTANI ACTIVISTS MATTERS TO YOU

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An article shared by Dr.Ehtesham

From The clarion project

5 Reasons Kidnapping of Pakistani Activists Matters to You

Up to nine secular activists have disappeared in Pakistan as families scramble for news. Here’s why their disappearances matters.
BY ELLIOT FRIEDLANDPrintEmail

Demonstrators demanding the recovery of missing activist Salman Haider outside the Karachi Press Club.

Over the weekend, several prominent Pakistani activists disappeared in mysterious circumstances. Activists from Pakistan are speculating that the government is behind the spate of disappearances in which at least four but possibly up to nine activists were kidnapped. Supporters of the missing activists have taken to the streets to demand they are recovered. They are sharing messages of support on social media using #RecoverSalmanHaider and #RecoverAllActivists.

Here are five reasons we should all care about what’s happening in Pakistan:

 These are the people fighting against the ideology of extremism

Pakistan is a large country which in the past has sheltered radical Islamist groups such as the Taliban. It’s where Osama bin Laden was able to hide out for years before he was finally brought to justice. One of the two founding fathers of modern extremist Islam, Abu A’la Maududi, was Pakistani.

Yet there is a growing movement of secularists in Pakistan who are struggling against the extremism within their country and who want to make Pakistan a better place. If they succeed, what we will see coming out of Pakistan is more and more educated integrated anti-extremist Muslims and less and less extremists affiliated with groups like the Taliban.

This will have a knock-on impact internationally and will reduce the amount of extremism in the world, including the amount of extremism in the United States. Their success will protect those who value secularism as a way of life around the world

If the activists currently disappearing in Pakistan are wiped out, Pakistan will become more extreme which will lead to the Muslim world in general becoming more extreme.

 Pakistan Has Nuclear Weapons

Pakistan just tested a nuclear-capable missile from a submarine. This development reportedly gives Pakistan second-strike capabilities, meaning that even if the country is wiped out by a nuclear strike, Pakistan would be able to respond by firing nuclear warheads from strategically-placed submarines.

If a country with such capabilities eliminates all its secularly-minded and rational thinkers and becomes completely overcome by theocratic Islamist ideology, then this nuclear arsenal will be in the hands of Islamist extremists.

That would be a serious national security risk to the United States of America.

 Other Countries Will Follow Suit

If the persecution of secularist and anti-extremist activist continues in Pakistan unabated and without significant international opposition, other countries will take note. Pakistan is a U.S. ally and the beneficiary of significant sums of aid money for decades. Last year, President Obama proposed $860 million in aid to Pakistan, which was a significant drop in the aid usually provided by the United States.

If America or other countries which have relations with Pakistan do nothing to stand up for the rights of secularists in Pakistan, countries such as Turkey and Indonesia will take note. The Turkish parliament is currently discussing increased powers for the Islamist President Tayyip Recep Erdogan. Indonesia is currently putting the governor of Jakarta (a non-Muslim) on trial for alleged blasphemy.

These countries may see America’s failure to protect secularism in Pakistan as a green light to persecute activists in their own countries.

 Refugees Will Increase

 A Free Pakistan Will Have A Stronger Economy

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5 Reasons Kidnapping of Pakistani Activists Matters to You