Life and Nature ~ Page 3 din 11

Big Bend National Park

The full moon rises high and clear over the Chihuahuan Desert. It’s autumn in the late 1700s. A couple of centuries from now—at the end of the 20th Century—the full moon at this time of year will bear the benign name Harvest Moon. But, in the 1700s, the inhabitants of northern Mexico call this the Comanche Moon. Each year, around the time of this autumn …

Monarchs butterflies – The Great Migration – from San Francisco to the Mexican border

The fourth and final generation of Monarchs for the year emerge from their pupae around late summer. External natural cues, perhaps the waning length of the day and cooler temperatures, cause a change in their bodies; their reproductive organs are immature, they are in a state of reproductive diapause. Unlike their parents that lived for only 2 to 5 weeks as butterflies, these fall adults …

Sharks saving humans

The anniversary of Steven Spielberg’s Jaws has come and gone and in the ensuing years, big-screen shark flicks haven’t shied away from the myth of the shark as a relentless killing machine and natural man-eater. Sharks aren’t necessarily deserving of the image, especially since the shark is now poised to save human lives. Throughout the sharks’ bodies are important chemicals that the animals need to …

Animal Sentinels vs Biological terrorism

Biological terrorism used in the U.S. might take hours or days to detect, as an infection slowly spread. U.S. hospitals don’t routinely share information about infections. Health officials dream of a computerized database connecting the nation’s health clinics and emergency rooms — but that dream is years from reality. In the meantime, Larry Glickman — who studies animal disease at Purdue University — says we …

What is a double helix?

“I’ve read that the shape of DNA is a ‘double helix.’ What is that?” If you could see a piece of DNA, it would look like a ladder that’s been twisted into a corkscrew shape . . . that’s the double helix. The rungs of the ladder are made up of pairs of chemicals — known by the first letters of their chemical names — …

What’s beyond the most distant star?

No one knows for sure because astronomers can’t see even as far as the farthest star. The sphere of space around Earth that we can see keeps growing as astronomers use new technologies. Right now astronomers can see about 14 billion light-years in any direction. That whole distance is filled with stars — in huge star islands called galaxies — all the way out. Astronomers …

The NEAR mission

The NEAR mission team was mostly from the Johns Hopkins University Applied Physics Laboratory. NASA began work on the Near-Earth Asteroid Rendezvous (NEAR) spacecraft in 1993 as part of its Discovery program of low-cost interplanetary exploration missions. NEAR left Earth on February 17, 1996. The spacecraft whizzed past the asteroid 253 Mathilde at a distance of 753 miles (June 27, 1997), then flew past Earth …

Living fossils

Given its large size, broad, flat face and slow, deliberate motion, divers could be forgiven for assuming the bluntnosed sixgill shark is a throwback to an earlier point in evolution. In fact, these deep-sea sharks aren’t very primitive at all. The shark’s sixth gill, a unique feature of its family the Hexanchiformes, and other parts of its well-adapted anatomy, are recent, specialized innovations. “They don’t …

Harvesting a medical bounty

Dr. Michael Zasloff knows a lot about frogs and the medical bounty in their skin. He is an expert on poison-frogs and the president of the Magainin Research Insitute of Magainin Pharmaceuticals. His company has relied on the chemicals found in several animals to produce a number of new drugs. Magainin developed the cancer-fighting drug, Squalamine (now in human trials in the U.S.) from chemical …

Turning to poison-dart frogs to save lives

High above the jungle floor, a howler monkey is breathing its last breath. Moments ago it felt fine. Now, however, thanks to a poison-tipped dart lodged into its leg, it feels numb and disoriented. It is having trouble breathing and its movements are laboured. Seconds later, it loses its grip on its perch and drops limply to the ground below. Not a nice way for …

Loss of habitat threatens poison-frogs – and your future health.

Continued from Part II For centuries, humans have turned to the plant kingdom for new medicines. Aspirin was derived from the bark of the willow tree. Digitalis, a heart medication, came from the foxglove plant. Codeine and morphine came from the poppy. And the cancer-fighting drugs vinblastine and vincristine are derivatives of the periwinkle plant. But we’re only now understanding the medical value that surrounds …

Shark Attack!

Got an idea that sharks are cold-blooded underwater predators? You’re partly right, but there are warm-blooded, or endothermic, sharks too — not to mention a few species which might provide lifesaving compounds. Read up on the exploits of the shark… Under the fin’s skin An international research team gets under the skin of unidentified shark fins to find out which species may be over-exploited. It’s …