In the world of giant pumpkins, a 500-pounder is a pip-squeak. “People don’t even blink at ’em,” says Danny Dill of Howard Dill Enterprises, which sells seeds whose DNA destines them for hugeness. The record is 1,689 pounds, set in 2007. “Within five years,” predicts Dill, “you’ll see a 2,000-pound pumpkin.”

What is a kilogram? It’s 2.2 pounds, of course. Or is it? The kilo is the only basic international standard pegged to a physical object—a 120-year-old platinum-iridium cylinder kept in a vault outside Paris and known as Le Grand K. In recent years scientists noticed slight variations in the cylinder’s weight. They’ve gone into high gear to redefine the kilo as a universal constant based on nature instead of an object vulnerable to distortion.

Quick, what’s faster than a speeding bullet and isn’t named Superman? The answer is the Bloodhound SuperSonic Car, or soon will be. Now being built in England, the jet-and-rocket-powered ride is designed to go, go, go 1,050 miles an hour. If it succeeds, it’ll blast past the current land speed record of 763 miles an hour, set in 1997 by Andy Green in the jet-propelled Thrust SSC. 

Angel the schnauzer strolled to the coffee table, stood up on his back legs, and pushed a nose toward the fruit platter. As dogs are known to do when food is left unattended. But this wasn’t just any dog—and his owner wasn’t just any owner. From across the room a sound rose, crisp and familiar to any fan of the Dog Whisperer, Cesar Millan. PSSHHT. A hand, tensed into a claw, rose in the air. The dog froze. Again: PSSHHT. (A commanding sound! Grabs attention and shows who's the boss!) Slowly, Angel backed down to the floor, walked away from the table, and curled up silently near his master's feet.

Somalia’s capital city of Mogadishu is a war zone. Rival militias, al Shabaab and Hizbul Islam, vie with each other as they try to overthrow the Transitional Federal Government, which struggles to hold on to a few key areas of the city. Bombings, kidnappings, and shootings are part of everyday life. Ironically, the food centers run by the Somali nonprofit SAACID are some of the safest places to be.

The “star,”  with some 100,000 nerve endings, gives Condylura cristata its sensitive touch. Claws give it scraping power. Photograph by Kenneth Catania

What outlandish snoot is this? A handy one that helps the star-nosed mole clock in as the fastest forager among mammals. As the mole claws at wetland soil or stream sediment, the tentacles about its nose probe up to 13 spots a second for invertebrates, insect larvae, and other prey. Then in 230 milliseconds—quicker than our eyes can flit to a fl ash of light—the mole scrutinizes and devours the edibles. That’s a record for pinpointing and eating food. (Bats are the likely runners-up.)

NGS grantee Yohannes Haile-Selassie, shown here at his dig in Ethiopia at Woranso-Mille, was the discoverer of the most complete specimen of Ardipithecus ramidus at nearby Aramis in 1994. He also discovered Ar. ramidus's 5.5 to 5.8 million-year-old ancestor, Ar. kadabba. Photo © Liz Russell, courtesy of Yohannes Haile-Selassie.

Today the world will witness the long-awaited roll out of Ardipithecus ramidus. And what a roll out! This new member of the hominin lineage has features that are quite unexpected because they are unlike what we see in living great apes, which share common ancestry with humans. A whole issue of Science is devoted to this creature and the work of a dedicated group of scientists who spent many years in the desolate Middle Awash project area of the Afar depression in Ethiopia.

I've had the pleasure of meeting many of the Middle Awash team members over the years. Among them are many Ethiopians who started their careers in the Middle Awash more than 15 years ago as bright, dedicated students. Now they are PhDs who are spread throughout the world at prestigious institutions making significant contributions to science, not the least of which are the many papers being announced today concerning the anatomy and environment of Ardipithecus ramidus.

Buried in these scientific papers is a significant mention that may pass right by many readers. In the paper entiltled "Ardipithecus ramidus and the Paleobiology of Early Hominids," the authors mention how in the early 1990s, after much looking, they were only finding scrappy bits of early human fossils at Aramis. They go on to say, however, that "... on 5 November 1994, Y.H. S. collected two hominid metacarpal fragments (ARA-VP-6/5001a and b) from the surface of an exposed silty clay..." Those hand bones were the first bits found of what would become the substance of much of today's press announcement—the most complete skeleton of an adult early hominin since the discovery of Lucy, the australopith, in 1974. Who is its discoverer, Y.H.S.? It was none other than Yohannes Haile-Selassie, one of the Ethiopian students I mentioned.

The big news in the journal Science tomorrow is the discovery of the oldest human skeleton—a small-brained, 110-pound female of the species Ardipithecus ramidus, nicknamed “Ardi.” She lived in what is now Ethiopia 4.4 million years ago, which makes her over a million years older than the famous “Lucy” fossil, found in the same region thirty-five years ago.

Buried among the slew of papers about the new find is one about the creature’s sex life. It makes fascinating reading, especially if you like learning why human females don’t know when they are ovulating, and men lack the clacker-sized testicles and bristly penises sported by chimpanzees.

One of the defining attributes of Lucy and all other hominids—members of our evolutionary lineage, including ourselves—is that they walk upright on two legs. While Ardi also walked on two legs on the ground, the species also clambered about on four legs in the trees. Ardi thus offers a fascinating glimpse of an ape caught in the act of becoming human.

The problem is it is doing it in the wrong place at the wrong time—at least according to conventional wisdom, which says our kind first stood up on two legs when they moved out of the forest and onto open savanna grasslands. At the time Ardi lived, her environment was a woodland, much cooler and wetter than the desert there today.

So why did her species become bipedal while it was still living partly in the trees, especially since walking on two legs is a much less efficient way of getting about?

He has a movie. And a book. And a bicycle that’s really kind of a rickshaw so his daughter can ride in a back seat. And a glass peanut-butter jar that he carries around as a vessel for drinking water.

Who is this “No Impact Man”?

Steve Holman, 52, is running 124.9 miles in the Sahara desert. All his food for the annual Marathon des Sables is in the 25-pound pack on his back (including potato chips he pulverized with a rolling pin to reduce bulk). In 100°F heat he struggles up a few 200-foot dunes, crawling on hands and knees at times. Alone in a sandstorm one night, not even sure he’s headed in the right direction, he thinks, Yes! This is why I’m here!

To the familiar divides—rich and poor, north and south, modern and traditional—add a new one: young and old. That’s because the average ages of the world’s populations are diverging, as some nations skew up or down. Youth booms persist in poor places like Uganda, where almost half the people (like this Kampala orphan, left) are under 15. Meantime, much of the industrialized world is aging. 

See age pyramids that compare the populations of Uganda and Japan.

Photos: Jessica Cudney (left); David McLain (right). Graphics: Mariel Furlong, NG Staff Sources: United Nations; Population Action International

It was little more than a decade ago at a meeting of the Society of Vertebrate Paleontology in New York City that rumors of feathered dinosaurs from China were swirling in the halls between sessions. The presence of feathers on dinosaurs not only implied a direct relationship between dinosaurs and birds, but it also raised questions about Archaeopteryx, the earliest known bird, and what it means to be a bird.

Today, at another meeting of the Society of Vertebrate Paleontology in Bristol, UK, Dr. Xu Xing of the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing announced the discovery of new geological formations in China, the Daohugou and Tiaojishan formations, that date to between 151 to 161 million years ago and contain more feathered dinosaur specimens. This announcement may bring what has been more than a decade of debate about dinosaur feathers and bird origins to a close. The reason is that one of the last remaining arguments used by opponents of the hypothesis that birds descended from dinosaurs was that the earliest bird, Archaeopteryx, actually predated the earliest feathered dinosaurs. That hurdle has now apparently been cleared. If the new dates for these beds are correct, they significantly predate Archaeopteryx, which lived around 150 to 145 million years ago. And there is no question that fossils found within these formations are feathered and very birdlike, particularly Anchiornis, a primitive troodontid.

I have been diving for eight days in the Phoenix Islands and have seen a range of situations underwater. Much of what I’ve seen has been severe stress on these remote ecosystems. Many of the coral reef habitats I have dived on have undergone bleaching events in recent years and are now just beginning to show signs of new life. It is actually a testimony to the overall good health of these reefs prior to the bleaching that they are able to rebound at all. So in terms of the future, these places should continue to rebuild and return to their once lush state.

A 64-year-old Duluth woman fell on the ice last December. Arthritis kept her from getting up. She lay in the snow for hours. Her temperature dipped to 70°F. Her heart stopped. She should have been a goner. But doctors revived her; today she is fine. Medical science is always learning more about how much a body can take. Yet as Duke University physician Claude Piantadosi notes, “At some point it’s impossible to rescue yourself.” —Shelley Sperry

• Take a quiz to test your knowledge of human endurance.

Art: Jason Lee

I'm used to folding laundry and bills. But when I was working on "Fold Everything," a short article about innovative uses of origami, my fingers began itching to try the ancient art of paper folding.

After all, there are people creating not only fantastic paper animal sculptures but using the mathematical principles of origami to build foldable telescope lenses and heart stents and to better understand how proteins fold. Origami for art’s sake has also come a long way. The father of 20th century origami, Akira Yoshizawa (1911-2005), created more than 50,000 unique figures. The most modern folders have something Mr. Yoshizawa didn’t: mathematical principals and computer programs that help them transform flat into functional, or just plain phenomenal.