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Why does life exist? Popular hypotheses credit a primordial soup, a bolt of lightning and a colossal stroke of luck. But if a provocative new theory is correct, luck may have little to do with it. Instead, according to the physicist proposing the idea, the origin and subsequent evolution of life follow from the fundamental laws of nature and “should be as unsurprising as rocks rolling downhill.” From the standpoint of physics, there is one essential difference between living things and inanimate clumps of carbon atoms: The former tend to be much better at capturing energy from their environment and dissipating that energy as heat. Jeremy England, a 31-year-old assistant professor at the Massachusetts Institute of Technology, has derived a mathematical formula that he believes explains this capacity. Kristian Peters Cells from the moss Plagiomnium affine with visible chloroplasts, organelles that conduct photosynthesis by capturing sunlight. Courtesy of Jeremy England Wilson Bentley

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Earth - Why are we the only human species still alive? Two million years ago in Africa, several species of human-like creatures roamed the landscape. Some looked surprisingly similar to each other, while others had distinct, defining features. In September 2015, another species was added to the list. Here's the tiny human twig in the Tree of Life Each Christmas, the BMJ (formerly the British Medical Journal) gets a little bit festive, releasing a special edition filled with goofy research papers. The science is real, but the topics are ridiculous. Last year, papers covered topics such as the origins of magic, how much James Bond really drank, and the physical responses to a public unicycler. This year, the highlight comes in the form of a paper led by a 15-year-old student Ben Alexander Daniel Lendrem, from the King Edward VI School in the UK, and his dad Dennis Lendrem, a statistician from the UK's Institute of Cellular Medicine, who studies the behaviour of human decision-making. The premise of their paper is their ‘Male Idiot Theory’ (MIT), and with this in mind, they examined all past winners of the infamous Darwin Awards. Interestingly, the Lendrems found that of the 318 cases reported to the Darwin Awards, 282 of them - so 88.7 percent - were performed by men.

Nature Wants Her Carbon Back  By looking down, things are looking up. Here's a little known fact about climate change: According to NOAA, if we could magically cut all current CO2 emissions worldwide to zero today (a feat even Merlin couldn't achieve) it would do nothing to stop climate change from continuing to get worse for centuries. Unless we actually draw some of the carbon already emitted back down to earth we are simply telling a 400-pound patient to gain weight a little more slowly. Amazingly, however, doing so may be significantly easier than reducing emissions. Life on Earth Is Older Than Rocks on Earth, Study Finds The Jack Hills of Australia. Image: NASA Scientists believe Earth is roughly 4.5 billion years old.

Biological classification The hierarchy of biological classification's eight major taxonomic ranks. Intermediate minor rankings are not shown. Modern biological classification has its root in the work of Carolus Linnaeus, who grouped species according to shared physical characteristics. These groupings have since been revised to improve consistency with the Darwinian principle of common descent.

10 Calories in, 1 Calorie Out - The Energy We Spend on Food In December, I attended Michael Pollan's lecture at the University of Texas’s Bass Concert Hall. My friend, Katie, had called me that morning to ask if I would be interested in joining her for the lecture - she knew that I had read three of Pollan's books on food and had also found out that there were $10 student tickets to be had for the lecture. Long story short at 7:40pm I found myself zipping down Guadalupe with Katie for my first Bass Concert Hall event in my tenure at UT. Pollan's lecture was interesting, engaging and funny. This was not surprising to me, after having read his books. The bags of groceries that he brought from the Fiesta across I-35 brought in the usual laughs ("Venom" who knew it was a drink??)

Fossil analysis pushes back human split from other primates by two million years LOS ALAMOS, N.M., Feb. 16, 2016—A paper in the latest issue of the journal Nature suggests a common ancestor of apes and humans, Chororapithecus abyssinicus, evolved in Africa, not Eurasia, two million years earlier than previously thought. “Our new research supports early divergence: 10 million years ago for the human-gorilla split and 8 million years ago for our split from chimpanzees,” said Los Alamos National Laboratory geologist and senior team member Giday WoldeGabriel. “That’s at least 2 million years earlier than previous estimates, which were based on genetic science that lacked fossil evidence.” “Our analysis of C. abyssinicus fossils reveals the ape to be only 8 million years old, younger than previously thought.

Biological organisation A population of bees shimmers in response to a predator. Biological organization, or the hierarchy of life, is the hierarchy of complex biological structures and systems that define life using a reductionistic approach.[1] The traditional hierarchy, as detailed below, extends from atoms (or lower) to biospheres. The higher levels of this scheme are often referred to as ecological organisation. Each level in the hierarchy represents an increase in organisational complexity, with each "object" being primarily composed of the previous level's basic unit.[2] The basic principle behind the organisation is the concept of emergence—the properties and functions found at a hierarchical level are not present and irrelevant at the lower levels.[3] Organisation furthermore refers to the high degree of order of an organism (in comparison to general objects).[4] Ideally, individual organisms of the same species have the same arrangement of the same structures.

Solar irradiance "Insolation" redirects here. It is not to be confused with Insulation. Solar irradiance is the power per unit area produced by the Sun in the form of electromagnetic radiation. Irradiance may be measured in space or at the Earth's surface after atmospheric absorption and scattering. Earth - A mysterious new species could be the earliest humans Two years ago an astounding new discovery shook up the field of early human evolution. The bones of a new species of extinct hominin called Homo naledi were discovered in the Rising Star Cave in South Africa and unveiled to the world in September 2015. The new species had a primitive braincase but fairly modern hands and feet, which is a strange mixture. To find out more, BBC Earth spoke to Professor Chris Stringer at London's Natural History Museum, where the reconstructed hand and jaw of H. naledi was on display as part of a new exhibition on human evolution.

Chronobiology Chronobiology is a field of biology that examines periodic (cyclic) phenomena in living organisms and their adaptation to solar- and lunar-related rhythms.[1] These cycles are known as biological rhythms. Chronobiology comes from the ancient Greek χρόνος (chrónos, meaning "time"), and biology, which pertains to the study, or science, of life. The related terms chronomics and chronome have been used in some cases to describe either the molecular mechanisms involved in chronobiological phenomena or the more quantitative aspects of chronobiology, particularly where comparison of cycles between organisms is required.