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Mollusks are fabulous architects. They build houses that protect their soft bodies from predators and the elements—shells of uncommon strength, durability and beauty. Many of these shells have spectacularly complex shapes—logarithmic spirals bedecked with fractal spines or other ornaments, all executed with near-perfect mathematical regularity. Yet mollusks, of course, know nothing of math. How, researchers have wondered, do these humble creatures produce such intricate patterns so precisely? For more than 100 years scientists have recognized that cells, tissues and organs must respond to the same physical forces that govern other kinds of matter....

John L. Callas of NASA’s Jet Propulsion Laboratory is project manager for the space agency’s Mars Exploration Rover mission, which landed the twin Spirit and Opportunity rovers on the Red Planet in January 2004. (Spirit touched down on Jan. 3 and Opportunity landed on Jan. 24, Pacific Time.) He contributed this article to SPACE.com’s Expert Voices: Op-Ed & Insights. No one ever expected this to happen. That after 10 years, a Mars Exploration Rover would continue to operate on the surface of Mars — well beyond its original 90-day mission....

Reconstructing the Very First Cell Unlike modern cells, with their mitochondria, pores, nuclei and such, the very first cell, which emerged some 3.5 billion years ago, was simple. It probably consisted of just a membrane with genetic information inside—raising the question of how it could take in nutrients and reproduce. Harvard Medical School researchers have built a model of what the first cell may have looked like. Using fatty acids that likely existed on a primeval Earth, they created a membrane porous enough to let in nutrients but strong enough to protect the genetic material inside....

The planet-killing Death Star may have been the ultimate weapon for the Empire in the “Star Wars” films, but it has no place in the United States military today, a White House official said on January 11. The statement, an official response a petition to begin building a real-life Death Star by 2016 on the White House’s We the People website, said President Barack Obama’s Administration cannot support building the science fiction weapon for several down-to-Earth reasons....

The Ultimate ComputerOnce a theoretical curiosity, the idea of a computer that stores information in quantum superpositions of 0 and 1, known as quantum bits or qubits, is edging slowly toward reality. This year researchers finally engineered microchips capable of rudimentary storage and manipulation of the quantum states of individual atoms, paving the way for convenient control over hundreds or thousands of atoms at once. Christopher Monroe of the University of Michigan at Ann Arbor (below) and David J....

Knowing when a dog is happy is easy, but spotting fear is a lot harder, as Michele Wan, a certified applied animal behaviorist, and her colleagues showed in research examining whether people’s perceptions of dogs’ emotions vary according to experience. In the study, published in PLOS ONE in 2012, volunteers—who were grouped as having little or no experience with dogs, having lived with a dog at some point, or working with dogs for more or less than 10 years—watched short video clips of dogs....

Humor has been touted as a panacea that boosts the immune system, smooths the way to success at work and even helps us to live longer. But for some people, chuckles are no laughing matter. Those who suffer from gelotophobia, or fear of being laughed at, dread even well-intentioned jokes. “They don’t trust friendly laughter—that someone is just enjoying themselves. Any laughter is bad laughter,” says psychologist Willibald Ruch of the University of Zurich, who pioneered research on the unusual condition in the mid-2000s....

People, Parasites, and Plowshares: Learning from Our Bodyampapos;s Most Terrifying Invaders Dixon D. Despommier Columbia University Press, 2013 ($28.95) Reading this book may make your skin crawl. Despommier, an emeritus professor of public health and microbiology at Columbia University, describes the biological feats of creatures that parasitize humans. The facts are horrifying and fascinating: the worm larvae that cause trichinosis, a disease caused by eating raw or undercooked meat, burrow into muscle tissue and instruct cells to build calcified cysts that serve as the worms’ homes....

Do you sometimes have memories of a mysterious past life? Recall odd experiences such as being abducted by aliens? Wonder where these memories come from and if, in fact, you were really once whisked off in a flying saucer by ETs? Seems the answer may be simpler than you think—or remember. A new study shows that people with memories of past lives are more likely than others to misremember the source of any given piece of information....

The threat of relapse hangs over any attempt to kick a heroin addiction. The results of a new study provide new clues as to which drug users may be at greater risk of sabotaging their treatment efforts. Scientists have identified a gene that plays a crucial role in controlling heroin craving and relapse behavior in rodents. The nucleus accumbens is a brain region important for processing pleasure and rewards; as such, it is central to heroin addiction....

Haruko Obokata, the stem-cell biologist whose papers caused a sensation earlier this year before being retracted, has resigned from the RIKEN Center for Developmental Biology in Kobe, Japan. Her emotional resignation letter was posted on RIKEN’s website on December 19 alongside results of the organization’s own investigation, which failed to confirm her claims of a simple method to create pluripotent stem cells. Such cells are scientifically valuable because they can develop into most other cells types, from brain to muscle....

From Nature magazine Like diabetes, most forms of cancer and other common diseases, there is no single gene that causes the autoimmune condition multiple sclerosis (MS). Dozens of genetic variations act in concert with environmental factors to cause the debilitating neurological disease. Yet a single genetic variant may explain why drugs that treat other autoimmune diseases tend to make MS symptoms worse, and could identify other MS patients who might benefit from the therapies....

Key concepts Physics Chemistry Density Liquids Introduction You probably know that when solid objects are placed in liquid, they can sink or float. But did you know that liquids can also sink or float? In fact, it is possible to stack different layers of liquids on top of one another. The key is that all the different layers must have different densities. You can stack them by picking several liquids with a range of densities or by varying the density of one liquid by adding chemicals such as sugar or salt to it....

Teeth from a cave in south China show that Homo sapiens reached China around 100,000 years ago—a time at which most researchers had assumed that our species had not trekked far beyond Africa. “This is stunning, it’s major league,” says Michael Petraglia, an archaeologist at the University of Oxford, UK who was not involved in the research. “It’s one of the most important finds coming out of Asia in the last decade....

As many as two thirds of stroke victims find themselves suddenly unable to comprehend music. Beyond bad karaoke, these people fundamentally cannot differentiate pitches or rhythms. The medical term is acquired amusia, and recently scientists have aggregated data from of a large group of people with this condition to pinpoint the critical brain regions involved. A study published in August in The Journal of Neuroscience found that the brain is incredibly modular when it comes to the perception of music and speech....

Sarah Mellnik was four years old when her doctors discovered the striking anomaly in her brain. She was missing the massive connective bridge that ordinarily unites the brain’s two hemispheres. This malformation can delay the development of verbal and motor skills, among other abilities. Today, however, Mellnik is a gregarious and active 29-year-old. She not only walks, she volunteers as an assistant dance teacher. These milestones did not come easily. In high school she endured other students’ taunts, disbelieving teachers and difficulties with class work....

In the delivery room, the (slight) odds are that a newborn is a baby boy, not a girl. Males make up 51.3 percent of live births in the U.S., a rate that has remained about constant for the past seven decades. Experts assumed that this male-skewed sex ratio began at conception, but a new analysis of fetal records shows that the chances overall of finding a boy or a girl start out at 50–50 and change over the course of pregnancy—leaning female, then male, then female again as nine months pass....

Sulla, the world’s first talking robot, was so adept at conversation—in four languages, no less—that a human visitor to the laboratory in which she was created refused to believe she was not a real person. Alas, Sulla was not a real robot, either, but a character in Karel Capek’s 1921 play R.U.R., which introduced the word “robot” to the lexicon. Ever since that debut, talking robots have seemed to be peeking around every corner, and not just in science fiction....

Whether or not astronomers agree with Prof. Lowell’s Martian theories, it cannot be denied that he has been by far the most indefatigable observer of our planetary neighbor. His studies have been elaborate and painstaking, and have involved not only the expenditure of years of time, but the erection of a private observatory in an atmosphere peculiarly fitted for his work. Based upon this foundation, any book of his on the subject deserves somewhat more consideration than the passing review which usually falls to the lot of a popular exposition of an important scientific investigation....

Researchers in Melbourne, Australia, are the first outside China to announce that they’ve grown the new coronavirus in cell culture. The group at the Peter Doherty Institute for Infection and Immunity says it isolated the virus from the first person diagnosed with the infection in Australia, on 25 January. The team will now share the virus with research labs around the world recommended by the World Health Organization (WHO) to help the development of more accurate diagnostic tests and vaccines, says Mike Catton, a deputy director of the institute....