Nuclear weapons are a preeminent threat to immediate human existence.
More than most, Japan is a nation whose modern history is tragically linked to the quest to use and tame nuclear power. This nuclear history is not noteworthy for its successes, but for how it reflects humanity’s capacity for destruction—and peace.
It has been 70 years since the U.S. atomic bombings of the Japanese cities of Hiroshima and Nagasaki, killing more than 400,000 people and affecting generations more through nuclear radiation. The horror of these bombings has been imprinted on our consciousness, holding at bay the further use of nuclear weapons in warfare.
These humanitarian catastrophes sparked a powerful peace movement in Japan that has been influential worldwide. It also gave rise to the country’s unique 1947 “Peace Constitution,” which renounces war and armed forces to resolve conflicts, except in self-defense. This legacy of peace has served Japan well, but it is now under threat. Prime Minister Shinzo Abe is pushing for deeply unpopular legislation to allow Japan to fight in foreign conflicts, effectively rewriting a part of the constitution that has become ingrained in the nation’s psyche.
These plans have met overwhelming public opposition, with polls showing the majority of Japanese people are against restarting nuclear reactors. Photo credit: Greenpeace / Jeremy Sutton-Hibbert
The campaign towards achieving global nuclear disarmament meanwhile remains a long way off. At the start of 2015, some 15,850 nuclear weapons were held in stock by nine states: the U.S., Russia, China, India, Pakistan, Israel, Britain, France and North Korea. Roughly 1,800 of these weapons are on high operational alert, according to the Stockholm International Peace Research Institute. These nine states continue to upgrade their nuclear weapons and research new ones.
We only have to look to the political wrangling over the breakthrough nuclear deal with Iran last month to witness the intractable nature of debates over who gets to wield the threat of nuclear weapons. The lack of political will on achieving disarmament meant no real progress was made in the latest review of the Treaty on the Non-Proliferation of Nuclear Weapons (NPT), held in May; the United Nations itself was forced to admit parties could not agree on substantive parts of the meeting’s final document.
Greenpeace itself has a history that is intertwined with nuclear energy: Our organization’s foundation campaign was the 1971 attempt by a small group of activists to stop U.S. nuclear tests on the island of Amchitka, Alaska. Forty-four years later, our understanding of the dangers of nuclear weapons proliferation and the attendant threats from nuclear energy, has only deepened, along with our core commitment to see it phased out. Nuclear energy, whether for military or civil purposes, is never peaceful. No nuclear program can ever be considered purely civil and always carries the threat of nuclear weapons development. And as the history of catastrophes in the nuclear energy sector proves, nuclear energy is neither safe, nor clean.
Nuclear energy, with its inherent environmental dangers and high costs, is increasingly unattractive as an alternative to fossil fuels. Instead, interest in renewable energy sources is surging in forward-looking economies and among investors, who know that continued fossil fuel dependence only drives conflict and distorts foreign policies.
But the threats are still there.
Nearly four and a half years ago, an earthquake sparked a triple-core reactor meltdown in a nuclear power plant in Japan, forcing tens of thousands of people to leave their homes. After investigations, Greenpeace Japan revealed last month that radiation in one of the most contaminated districts is still so widespread and at such a high level that those who were evacuated cannot return home safely, despite decontamination efforts.
Japan’s operating reactors are currently shut pending safety checks, but the nation is planning to restart its first nuclear reactor this month. These plans have met overwhelming public opposition, with polls showing the majority of Japanese people are against restarting nuclear reactors. A Greenpeace petition opposing the nuclear restart has gathered tens of thousands of signatures.
At the core of Greenpeace is a conviction that conflict and the ways it manifests in violent struggles over our natural resources, will destroy our planet and all of us. So we have to find better ways to resolve these issues. Our non-proliferation campaign over the decades is part of a global peace movement that aspires to social justice and environmental sustainability. Even as we see setbacks to achieving peace in our time, we are convinced that non-violent resistance and protest will achieve this change. History shows that peaceful opposition is far more effective than violence will ever be.
It should be unthinkable that the horror in Hiroshima and Nagasaki 70 years ago would ever be revisited upon anyone anywhere in our world today. Neither should the trauma felt by Japanese people after the Fukushima accident—and also by thousands of people affected by other nuclear disasters, such as Chernobyl—ever again be endured. Our remembrances for this occasion are also reminders to continue our journey towards peaceful change.
Kumi Naidoo is the International Executive Director of Greenpeace.
A new chapter in space flight began this week in 1950 July with the launch of the first rocket from Cape Canaveral, Florida: the Bumper V-2.
Shown above, the Bumper V-2 was an ambitious two-stage rocket program that topped a V-2 missile base with a WAC Corporal rocket. The upper stage was able to reach then-record altitudes of almost 400 kilometers, higher than even Space Shuttles once flew. Launched under the direction of the General Electric Company, the Bumper V-2 was used primarily for testing rocket systems and for research on the upper atmosphere.
Bumper V-2 rockets carried small payloads that allowed them to measure attributes including air temperature and cosmic ray impacts. Seven years later, the Soviet Union launched Sputnik I and Sputnik II, the first satellites into Earth orbit. In response in 1958, the US created NASA.
Tens of millions of people have flocked to theatres this summer to see Jurassic World, an action flick “starring” a team of trained Velociraptors that hunt genetically modified dinosaurs on command of their human master.
It’s a preposterous storyline of course, but very entertaining. I study dinosaurs for a living and it didn’t bother me to see Velociraptors being used as hunting dogs for the sake of good cinema. What I didn’t like, however, was that the Velociraptors were depicted as big, drab-coloured, scaly brutes.
That’s because the real Velociraptor was a lapdog-sized predator covered in feathers. Palaeontologists have known this for a while. If you look at the arm bones of Velociraptor you can see a row of bumps, identical in size and shape to the quill knobs of living birds: the anchor points for big wing feathers. But because Velociraptor hasn’t been found in the perfect geological settings that fossilise soft tissues, we don’t know exactly what its feathers would have looked like.
But we have a better idea now, thanks to the discovery of a spectacular new dinosaur from northeastern China that I studied with my colleague, Junchang Lü of the Chinese Academy of Geological Sciences.
Our new dinosaur, Zhenyuanlong, is one of the closest cousins of Velociraptor. Its gorgeous chocolate-coloured skeleton was found by a farmer in 125-million-year-old rocks that were laid down in a quiet lake buried by volcanic ash. It’s just the right environment for preserving the soft bits that usually decay before a fossil is formed.
Zhenyuanlong is covered in feathers. Simple hairy filaments coat much of the body, larger veined feathers stick out from the tail, and big quill-pen-feathers line the arms, layered over each other to form a wing. This is a dinosaur that looks just like a bird. If you could see it alive you would probably make no distinction between it and, say, a turkey or a vulture.
Look at Zhenyuanlong and you see what the real Velociraptor would have been like. Far from being a scaly-skinned reptilian monster, Velociraptor would have been a fluffy, feathered poodle from hell.
Dinosaurs such as Zhenyuanlong and Velociraptor are some of my favourite fossils to study. They fascinate me because they capture evolution in action. These small, fast-running, brainy predators are some of the closest relatives of birds. They are chapters in one of the greatest stories in the history of life: the evolutionary transition between fearsome carnivorous dinosaurs and their 10,000 feathered descendants that live on today, all over the world.
And this is why the discovery of Zhenyuanlong is really important. It gives us new insight into this incredible moment in evolution. Zhenyuanlong is fairly large for a close relative of birds, two metres long from snout to tail. It also has much shorter arms than Velociraptor or birds. A big, short-armed animal probably wasn’t flying, so what was it doing with its wings? We don’t know for sure.
This opens up a whole new mystery for us to solve: why did wings evolve? Did they evolve for flight, or did they first develop for something else, and were later co-opted to be used as an airfoil? We don’t know the answer yet, but since new fossils of bird-like dinosaurs are being found at an incredible rate, maybe we’ll have it solved by the time the next Jurassic Park comes out.
In the past decade, the analysis of ancient DNA from fossil skeletons of anatomically modern humans has revealed a startling fact: some of our direct ancestors had sex with Neanderthals, producing fertile offspring. Prior to these genetic revelations, anthropological researchers were divided between those who firmly believed that such unions either did not occur, or that they could not have yielded sexually fertile offspring, because the differences between early modern humans and Neanderthal genomes would have been too great.
Now that the closeness between the DNA of early modern humans and Neanderthals has been established, geneticists have begun to find a few rare fossils that contain a mixture of the two. A new study presents the latest and perhaps most intriguing of these discoveries: A fossil jawbone of a male, human skull that has been radiocarbon dated at 37,000 to 42,000 years ago. The fossils came from a site called Peştera cu Oase in Romania, making it one of the oldest early modern humans known from Europe.
The fact that this individual carried more Neanderthal DNA than any other anatomically modern human ever tested is surprising and means that the mating between a Neanderthal and a modern human took place as recently as in his great-grandfather’s generation. Statistical analysis of the DNA composition of the skeleton suggests that the person carried as much as 8-11% Neanderthal genes in his DNA.
The enigma of modern Europeans’ DNA
Surprisingly, in spite of the two populations being in contact for many thousands of years, there is no DNA evidence for interbreeding between Neanderthals and the ancestors of the Europeans living today. In fact, segments of Neanderthal DNA turn up in modern human DNA from East Asians and Native Americans far more than they do from Europeans. But if the anatomically modern human population of ice-age Romania did interbreed with Neanderthals, then why didn’t the Neanderthal DNA signature carry through to modern Europeans?
The research sheds some light on this conundrum as well. It appears that the ancient Romanians were not the direct ancestors of modern Europeans. Instead it was immigrant populations of early humans originating from the Middle East and southeast Europe that passed on their genes while sweeping through Europe, bringing farming and animal husbandry with them. This new lifestyle replaced the hunter-gather way of life that had characterised all previous human societies.
Other ancient skeletons of modern humans from Eurasia help flesh out the story of relations between Neadnerthals and humans from the last ice age. An individual from the Kostenki 14 site in western Russia shared from 1.7-3.8% DNA with Neanderthals (Location 2 on the map). This skeleton was dated to 36,000-39,000 years old, and the individual was more closely related to later Europeans than to East Asians.
The studies of the Kostenki 14 and Ust’-Ishim specimens show that gene flow from Neanderthals to modern humans at these sites occurred well before these individuals lived. In the latter case, it could have been around a thousand years before the Ust’-Isham individual lived – much earlier than in Romania.
The fascinating findings, made thanks to the rapid advances in genome sequencing that we’ve seen over the past decade, represent important but small pieces of the puzzle describing the origin of the humans living today. No doubt will many more secrets be unveiled in the near future.
For one thing, finding mosquitoes that had drunk the blood of dinosaurs and then been preserved in amber for hundreds of millions of years is incredibly unlikely. But there’s another more important reason: organic molecules such as proteins and DNA degrade fast after a creature’s death. They are almost never found preserved in bones older than a few thousand years. This has been the dogma for many years.
The idea of molecular-level preservation within fossils has always been controversial. No DNA has ever been extracted, for example, from a dinosaur bone precisely because this complex molecule degrades away over relatively short periods of geological time.
But other kinds of molecular and cellular preservation have been reported in fossils, including blood cells, skin cells and the original cellular components of feathers and muscles. The preservation of these kinds of cells and molecules has always been assumed to be extremely rare, only likely at sites of exceptional preservation.
In the case of dinosaur feathers and skin cellular preservation, sites like the Jehol Biota fossil deposit of western China (where rocks are around 120m years old), have proved important because animals are preserved in incredible detail in a fine-grained laminated sediment.
A new study by Sergio Bertazzo and colleagues, most based at Imperial College in London, looks set to change this perception. It suggests preservation of organic remains might be much more common that has always been assumed.
Bertazzo’s team studied a series of Canadian dinosaur bones, all about 80m years old, using state-of-the-art analytical techniques to examine the surfaces and internal composition of the fossils at very small scales. Intriguingly, not all of the team’s dinosaur bones were exceptionally preserved. They were just ordinary chunks of bone, the kind very often collected by palaeontologists from Mesozoic-era (the period when dinosaurs lived) sites around the world.
The researchers analysed the fossils at the nanoscale, using an electron microscope to reveal details smaller than can be seen with light, and a mass spectrometer to analyse their chemical composition. The study identified clear structures in the fossils that were consistent with the preservation of original bone collagen, the protein component of all vertebrate bones.
The structures seen in the Canadian bones might not be pretty, but this is a hugely important piece of work that changes our perception of how and why soft tissue are preserved in fossil bones.
Unfortunately, it doesn’t make a Jurassic Park-style theme park any more feasible because the DNA in the cells had still degraded. But at least we have more information about cell shapes and the preservation of proteins that make up bones.
The potential to identify cellular structures and their organic components also means further studies on extinct animals, long thought largely impossible, might indeed be doable using the techniques highlighted in this paper if more cells are found.
One clear area that could use these results would be the hugely debated field of dinosaur physiology. Were dinosaurs really warm-blooded with a faster metabolism like living birds, or were they more reptilian in their biology?
We might not (yet) be able to bring dinosaurs back to life, but we are moving towards understanding much more about their fossil preservation and biology than ever thought possible.
This article was changed after publication to correct an error introduced during the editing process
Look at a primate or a Neanderthal skull and compare it with a modern human’s. Notice anything missing?
We have one feature that primates, Neanderthals, archaic humans—any species, for that matter—don’t possess: a chin.
“In some way, it seems trivial, but a reason why chins are so interesting is we’re the only ones who have them,” says Nathan Holton, who studies craniofacial features and mechanics at the University of Iowa. “It’s unique to us.”
New research led by Holton and colleagues at the UI posits that our chins don’t come from mechanical forces such as chewing, but instead results from an evolutionary adaptation involving face size and shape—possibly linked to changes in hormone levels as we became more societally domesticated.
The finding, if true, may help settle a debate that’s gone on intermittently for more than a century why modern humans have chins and how they came to be.
Using advanced facial and cranial biomechanical analyses with nearly 40 people whose measurements were plotted from toddlers to adults, the UI team concludes mechanical forces, including chewing, appear incapable of producing the resistance needed for new bone to be created in the lower mandible, or jaw area. Rather, they write in a paper published online in the Journal of Anatomy, it appears the chin’s emergence in modern humans arose from simple geometry: As our faces became smaller in our evolution from archaic humans to today—in fact, our faces are roughly 15 percent shorter than Neanderthals’—the chin became a bony prominence, the adapted, pointy emblem at the bottom of our face.
“In short, we do not find any evidence that chins are tied to mechanical function and in some cases we find that chins are worse at resisting mechanical forces as we grow,” says Holton, assistant professor and anthropologist in the Department of Orthodontics at the UI College of Dentistry. “Overall, this suggests that chins are unlikely related to the need to dissipate stresses and strains and that other explanations are more likely to be correct.”
More intriguing, UI anthropologists led by Robert Franciscus think the human chin is a secondary consequence of our lifestyle change, starting about 80,000 years ago and picking up great steam with modern humans’ migration from Africa about 20,000 years later. What happened was this: Modern humans evolved from hunter-gatherer groups that were rather isolated from each other to increasingly cooperative groups that formed social networks across the landscape. These more connected groups appear to have enhanced the degree to which they expressed themselves in art and other symbolic mediums.
Males in particular became more tranquil during this period, less likely to fight over territory and belongings, and more willing to make alliances, evidenced by exchanging goods and ideas, that benefited each and all.
The change in attitude was tied to reduced hormone levels, namely testosterone, resulting in noticeable changes to the male craniofacial region: One big shift was the face became smaller—retrenching in effect—a physiological departure that created a natural opportunity for the human chin to emerge.
“What we’re arguing is that modern humans had an advantage at some point to have a well-connected social network, they can exchange information, and mates, more readily, there’s innovation,” says Franciscus, who was on the team that first laid out the theory in a paper published last August in the journal Current Anthropology and is a contributing author on the current paper, “and for that to happen, males have to tolerate each other. There had to be more curiosity and inquisitiveness than aggression, and the evidence of that lies in facial architecture.”
The new study buttresses that argument, in that it seems to rule out the chin arose from mechanical exertion, such as chewing.
The researchers examined how the jaw region generally reacted to two forces—vertical bending and wishboning. In wishboning, one side of the jaw is pulled outward, resulting in compression in the outer part of the chin. In vertical bending, the ramus—the posterior more or less vertical part on each side of the lower jaw—splays outward, tensing the chin area. In both instances, the thinking went, the chin area is being mechanically stressed; on a microscopic level, new bone is being created, much like lifting weights creates little tears that allows new muscle to be created. Thus, arose the theory that mechanical forces, such as chewing, led to our chins.
But in examinations from periodic measurements of participants’ heads from 3 years of age to more than 20 years old, the UI researchers found no evidence that these imperceptible mechanical forces led to new bone in the chin region. Instead, they found nearly the opposite: Individuals with the most mechanical resistance had chins most similar to a 3 -or 4-year-old—meaning they didn’t have much of a chin at all.
What the researchers did notice is chin “growth” has more to do with how each feature in our face adapts as our head size increases, much like you’d fit individual pieces together in an expanding, shape-shifting, three-dimensional puzzle.
Children, for example, have flat, nearly imperceptible chins, much like what’s seen in Neanderthals. That bony prominence only becomes visible as our heads and faces grow into adulthood.
“Our study suggests that chin prominence is unrelated to function,” Holton says, “and probably has more to do with spatial dynamics during development.”
The above story is based on materials provided by University of Iowa. The original article was written by Richard C. Lewis. Note: Materials may be edited for content and length.