Ancient beads imply culture older than we thought
Archaeologists have discovered that 100,000-year-old shells found in Israel and Algeria were decorative beads. This suggests that modern human forms of behaviour, such as language, developed earlier than previously thought. "Personal ornaments are a powerful tool of communication," says Francesco D’Errico at the Institute of the Prehistory and Geology of the Quaternary in Talence, France, one of the team that studied the beads. "They can indicate social or marital status, for example. But you need to have a complex system of language behind that. To me [these beads] are very powerful archaeological evidence that these people were able to speak like us."
In 2004 archaeologists unearthed 41 pea-sized shell beads in Blombos Caves, South Africa, dated at 75,000 years old. The shells were all punctured in the same place and showed signs of wear, as if they had been strung together. They were the oldest record of personal ornamentation ever found, suggesting that African humans from this time could think symbolically and were more culturally advanced than previously believed.
That find prompted Marian Vanhaeren at University College London and her colleagues to take a further look at shells mentioned in site excavation logs from Skhul in Israel and Oued Djebbana in Algeria. The team found three shells of the ocean gastropod Nassarius gibbosulus in museums in London and Paris. Two were from Skhul, dating from at least 100,000 years ago, and one was from Oued Djebbana and between 35,000 and 90,000 years old. The snail is of the same genus as those found in the Blombos Caves, and all the finds were too tiny to be collected as food. Each shell had a hole on the back, most likely punctured by humans, though such holes do occur naturally.
Full Aricle, -New ScientistOldest spider web found in amber
The location of the spider silk strands have been drawn on this image. Magnified images of a mite and bubbles attached to a strand are shown in boxes. The scale bar is 1 millimetre long. (Image: Science)The world's oldest spider web – complete with captured prey - has been discovered, preserved in 110-million-year-old amber
The world's oldest spider web – complete with captured prey - has been discovered, preserved in 110-million-year-old amber.
The web was trapped in the early Cretaceous period as sticky sap seeped from a tree in what is now Spain. It had hung from a tree so that it would catch insects on the wing.
The sap may have dripped onto the web, or the web may have blown onto its surface, says David Grimaldi of the American Museum of Natural History in New York, US. Then more sap covered it, forming a small amber "stalactite" 18 millimetres long and 7.5 millimetres wide.
Palaeontologists who found the amber sliced it into three thin sections, revealing at least 26 silk strands, some interconnected. The web is not complete enough to be firmly identified as an orb web, with a spiral strand wound on radial spokes. But Grimaldi says the fragments are consistent with orb webs. "It's a geometrically complex web, certainly not a random assortment of strands like a cobweb. It was certainly in one plane,"
 Dogs such as beagles can be trained to perform complex tasks |
Belle the beagle triggered a call to an ambulance crew by biting on her owner, Kevin Weaver's, mobile phone.
The dog was trained to detect potential diabetic attacks by licking and sniffing Mr Weaver's nose to check his blood sugar levels and pawing him.
Belle resorted to dialling for help when Mr Weaver fell unconscious.
The dog used her teeth to press the number nine key, which the phone was programmed to interpret as a "911" call to emergency services.
Ambulance workers answered the phone and, hearing nothing but barking at the end of the line, rushed to the caller's house in the city of Ocoee in Florida state.
The dog is the first animal to receive the Vita Wireless Samaritan Award.
"I am convinced that if Belle wasn't with me that morning, I wouldn't be alive today," Mr Weaver said.
"Belle is more than just a life-saver. She's my best friend."Source, -BBC News
 | Scientist Targets 2024 for China's First Moon Walk By Associated Press |
SHANGHAI, China (AP) – China plans a manned lunar mission by 2024 that will include a walk on the moon's surface, a top Chinese scientist was quoted as saying in a Hong Kong newspaper.
The program went into overdrive following China's first successful manned space mission in 2003 and may include a spacewalk by an additional manned mission next year.
Named “Chang'e'' after a mythical Chinese moon-inhabiting fairy, the lunar program will begin with the launch next spring of a 2-ton moon orbiting satellite, the program's chief scientist Ouyang Ziyuan was quoted as saying in the official Shanghai Daily newspaper.
The orbiter is due to stay in space at least a year and record images of the lunar surface, study lunar microwaves, the distribution of usable metals, and the thickness of lunar soil.
Orchid Has "Active" Sex With Itself.
An agile Chinese orchid performs a floral version of sexual intercourse—with itself.
Researchers say an extension of the male flower part, or anther, turns an upside-down loop to deliver spermlike pollen spores directly into the female cavity.
The anther bends to enter the female chamber from below and is secured in place by a ring structure on its stalk to ensure fertilization.
The flower is the first known plant in which pollination is entirely self-directed, with no outside agents or forces—such as bees or breezes—playing a role.
Biologists observed the elaborate style of reproduction in the bisexual orchid Holcoglossum amesianum, a tree-dwelling plant found in the dry forests of China's southern Yunnan Province
LaiQiang Huang of Tsinghua University in Shenzhen and colleagues studied the unusual flower. The team's findings will appear in tomorrow's issue of the journal Nature.
Pollinating Alone
In more conventional plant sex, creatures such as insects or birds transport pollen from one plant to another, resulting in a fertilized embryo or seed.
Most orchids reproduce in this way, and many are known for their elaborate floral structures (photo: South African Disa uniflora orchid) designed to attract specialized insect pollinators.
But pollen may also be transferred from male to female flowers on a single plant, or from male to female parts on a single blossom. In such cases, plants can fertilize themselves.
While less common in orchids, many flowering plants are known to self-fertilize either some or all of the time. Most rely on wind or fluid secretions to move pollen around.
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