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4 April 2017
3 April 2017
Nautilus Magazine: Survival of the Friendliest
But we know now that that picture is incomplete. Evolutionary progress can be propelled both by the competitive struggle to adapt to an environment, and by the relaxation of selective forces. When natural selection on an organism is relaxed, the creative powers of mutation can be unshackled and evolution accelerated. The relief of an easier life can inspire new biological forms just as powerfully as the threat of death.
One of the best ways to relax selective forces is to work together, something that mathematical biologist Martin Nowak has called the “snuggle for survival.” New research has only deepened and broadened the importance of cooperation and lifting of selective pressures. It’s a big, snuggly world out there. [...]
We tend to conceive of life as separate from its habitat: The environment is a kind of container, and life is like a liquid that adapts to fill it. Sir Arthur Tansley introduced the concept of the ecosystem in 1935. He believed nature operated like a machine, and so, like an engineer, sought to map the flow of energy and matter through life and its environment. But an ecological niche is not, as I’d gathered from building shoebox dioramas in second grade, the raw physical parameters of an animal’s environment: salinity, alkalinity, humidity, temperature. It’s a web of relations, not just between a species and its habitat, but also with all the other species co-existing in the same space. A niche is no less dynamic than evolution is, contrary to Tansley’s mechanistic vision. “Palaeontologists often say that a burst of diversity in the fossil record simply ‘filled in ecological space,’ as if each new species simply took up residence in a square of a pre-existing chessboard,” writes paleobiologist Douglas Erwin. He suggests that a better analogy is that species build the chessboard themselves. Corals, for example, form their own protective niche by building reefs, which slow currents and reduce erosion on themselves. Reefs also serve to house countless other species, many of which have in turn evolved behaviors to protect corals. If an organism can modify its niche—by altering itself or its relationships with other species—it has the chance to build the world in which its future progeny will evolve, reshaping it to better ensure their survival.
Jacobin Magazine: Europe’s False Choice
The celebrations in Rome were marked by the publication of a white paper in which European Commission president Jean-Claude Juncker established various possible scenarios for the EU’s future — keep the current rhythm, step on the accelerator, apply the brakes, or go into reverse. Not a word was offered on the substance, the policies, that would define these routes. Nothing on youth unemployment, the migration crisis, cuts, violence against women, or climate change. In an umpteenth display of ignorance, Europe’s elite closed their eyes to the crises affecting the continent and the concerns of those experiencing them. [...]
With its aggressive foreign policy, the European Union has intensified conflicts around the world and contributed to fresh waves of forced migration. With its police management of its borders, it has turned the Mediterranean into an enormous mass grave, asylum into an exception and immigration into a danger for whoever is fleeing from bombs and misery. With its institutional xenophobia, the EU has normalized the discourse and proposals of the new radical right formations and the xenophobic populism that are today spreading across Europe, a specter of the past now Le Pen-izing minds across the continent. [...]
Sixty years ago, what is today the European Union was born as a project to create a single market, a customs union, and greater coordination between states in coal mining and steel production. Extractivism, free competition, and commodity circulation are the germ of the European project. Let’s not trick ourselves by presenting the policies of the last decade as somehow exceptional. Market logic and monetary and budget questions have always been the priority. [...]
We could say that today Europe is in dispute. They want to trap us in a false dichotomy where we have to choose between a neoliberal EU or a xenophobic retreat into the nation. This choice is not only a trick, it is a mutually reinforcing one.
We need a Plan B for Europe — and its problem is not its speed, but its direction. Let’s start to give form to a European project that recovers the roots of democracy in partisan antifascism, solidarity, peace, and social justice. A European project that neither excludes nor expels anyone, for it is a project no one would want to walk away from. That task has today become as urgent as it is indispensable.
The Atlantic: The Evolution of the Tomb of the Unknowns
For years, sentinels guarding the Tomb of the Unknowns at Arlington National Cemetery voluntarily had their lives defined by four constant and silent witnesses: the Unknown of World War I, the Unknown of World War II, the Unknown of the Korean War, and the Unknown of the Vietnam War. Until 1998. That’s when the Unknown of the Vietnam War was identified as First Lieutenant Michael Joseph Blassie. The tombs—the first of which was erected in 1921—represent the American soldiers who died in conflict and were never identified. Blassie was originally tallied as one more unidentified service member lost to the war, either missing or killed in action. In the longer course of history, however, he came to occupy a place at the nexus of old and new in how the United States cares for its dead. [...]
A rise in both care and capability borne out over centuries of warfare has caused the number of unidentified to gradually dwindle. Only three individuals who took part in Operation Iraqi Freedom from 2003 to 2010 have yet to be accounted for, according to the Defense POW/MIA Accounting Agency, which is responsible for the recovery of missing personnel. It’s a considerable drop from the thousands of American service personnel unaccounted for from past wars. The reasons for the decline are varied, but include both the changing character of war as well as advances in technology like DNA testing, which have made unknowns largely a phenomenon of the past. “The generation that the tomb was built for, and the unknown soldier honored and buried here … that generation of people has come and gone,” said Sergeant of the Guard Paul K. Basso. [...]
“Today, the tomb and the unknown soldiers continue to serve their original purpose, and that’s important,” said Basso, “but they also serve a whole new purpose for many Americans and the world.” War losses may now be identifiable, but they are no less poignant or profoundly grieved. After all, when visitors make the trek up to the tomb, take in the landscape, align their various screens to best capture the grandeur of the space, and hit send on their social-media accounts, those crypts—including the fourth—lie in full view. And maybe that’s enough.
Nautilus Magazine: There’s Mysteriously Large Amounts of Methane on Mars
Almost no matter where the methane comes from, it’s an intriguing discovery. If you dropped a molecule of methane into the atmosphere of Mars, it would survive about 300 years—that’s how long, on average, it would take for solar ultraviolet radiation and other Martian gases to destroy the molecule. By rights, the Martian atmosphere should have been scrubbed of its methane eons ago. So, the methane we see must come either from a source that is producing methane today or from a subsurface reservoir that is venting methane produced sometime in the past. On Earth, 95 percent of methane is biological in origin. The class of bacteria known as methanogens feeds on organic matter and excretes methane. They populate our planet’s wetlands, which account for nearly a quarter of the methane present in the Earth’s atmosphere globally. Cows’ gut bacteria are the second largest producers. It is the possibility of microbial life that has propelled the search for methane on Mars.
But even if the methane there comes from geologic processes, it would give us a profound new respect for what looks outwardly like a geologically dead world. Methane can be produced by the geochemical process of serpentinization, which is widespread in Earth’s crust, especially at warm and hot hydrothermal vents on the ocean floor known as Lost City and Black Smokers. This process requires a source of geologic heat as well as liquid water. Those happen to be two main ingredients of life, as well. [...]
Surprisingly, during a single two-month period, four sequential observations reported a spike of 7 ppbv. These values were much too high to explain by comets, meteorites, or dust. They must have been of Martian origin—perhaps a burp from a relatively small and localized subsurface source to the north of the landing site. The Martian winds would blow that methane away over several months, explaining why the signal went away when it did. Alternatively, that pulse could be from a distant and much bigger source, which would require some other unknown mechanism to remove methane quickly. Like the earlier observations of plumes, the spikes seen by Curiosity remain a tantalizing clue to a still-enigmatic Mars.
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