"MISSING LINK" FOUND: New Fossil Links Humans, Lemurs?

Meet "Ida," the small "missing link" found in Germany that's created a big media splash and will likely continue to make waves among those who study human origins.

In a new book, documentary, and promotional Web site, paleontologist Jorn Hurum, who led the team that analyzed the 47-million-year-old fossil seen above, suggests Ida is a critical missing-link species in primate evolution (interactive guide to human evolution from National Geographic magazine).

(Among the team members was University of Michigan paleontologist Philip Gingerich, a member of the Committee for Research and Exploration of the National Geographic Society, which owns National Geographic News.)

The fossil, he says, bridges the evolutionary split between higher primates such as monkeys, apes, and humans and their more distant relatives such as lemurs.

"This is the first link to all humans," Hurum, of the Natural History Museum in Oslo, Norway, said in a statement. Ida represents "the closest thing we can get to a direct ancestor."

Komodo Dragons Kill With Venom, Researchers Find

Komodo dragons kill using a one-two punch of sharp teeth and a venomous bite, scientists have confirmed for the first time.

The find dispels the common belief that toxic bacteria in the Komodos' mouths are responsible for ultimately killing the dragons' prey.

An animal that escapes a Komodo's initial attack soon weakens and dies. The fierce carnivore tracks the wounded creature and dines at its leisure once the prey collapses.

Researchers have long thought that the Komodo dragon, native to Indonesia, kills via blood poisoning caused by the multiple strains of bacteria in the dragon's saliva.

But "that whole bacteria stuff has been a scientific fairy tale," said Bryan Fry, a venom researcher at the University of Melbourne in Australia.

Fry and colleagues studied the biochemistry of Komodo venom after they had the rare opportunity to examine two dragons from zoos that both had to be put down due to terminal illnesses.

The team found that the dragon's venom rapidly decreases blood pressure, expedites blood loss, and sends a victim into shock, rendering it too weak to fight.

In the venom, some compounds that reduce blood pressure are as potent as those found in the word's most venomous snake, western Australia's inland Taipan.

Komodo Combo Attack

While his colleagues expressed surprise at the findings, Fry said he wasn't so shocked.

His earlier research had shown that other lizard species—such as iguanas, legless lizards, and monitor lizards—are also venomous.

In fact, Fry estimates that close to a hundred of the more than 5,000 known lizard species use venom.

Ancient Gem-Studded Teeth Show Skill of Early Dentists

The glittering "grills" of some hip-hop stars aren't exactly unprecedented. Sophisticated dentistry allowed Native Americans to add bling to their teeth as far back as 2,500 years ago, a new study says.

Ancient peoples of southern North America went to "dentists"—among the earliest known—to beautify their chompers with notches, grooves, and semiprecious gems, according to a recent analysis of thousands of teeth examined from collections in Mexico's National Institute of Anthropology and History (such as the skull above, found in Chiapas, Mexico).
Scientists don't know the origin of most of the teeth in the collections, which belonged to people living throughout the region, called Mesoamerica, before the Spanish conquests of the 1500s.

But it's clear that people—mostly men—from nearly all walks of life opted for the look, noted José Concepción Jiménez, an anthropologist at the institute, which recently announced the findings.

"They were not marks of social class" but instead meant for pure decoration, he commented in an e-mail interview conducted in Spanish.

In fact, the royals of the day—such as the Red Queen, a Maya mummy found in a temple at Palenque in what is now Mexico—don't have teeth decorations, Jiménez said.

Other evidence of early Mesoamerican dentistry—including a person who had received a ceremonial denture—has also been found.

Knowledgeable Dentists
The early dentists used a drill-like device with a hard stone such as obsidian, which is capable of puncturing bone.

"It's possible some type of [herb based] anesthetic was applied prior to drilling to blunt any pain," Jiménez said.

The ornamental stones—including jade—were attached with an adhesive made out of natural resins, such as plant sap, which was mixed with other chemicals and crushed bones, Jiménez said.

The dentists likely had a sophisticated knowledge of tooth anatomy, Jiménez added. For example, they knew how to drill into teeth without hitting the pulp inside, he said.

"They didn't want to generate an infection or provoke the loss of a tooth or break a tooth."

—John Roach

Photograph courtesy José C. Jiménez López

Earliest Known Human Ancestor

Does this facial reconstruction depict our earliest known human ancestor? In 2002 paleontologists digging in Chad, Africa, unearthed a skull and other seven-million-year-old fossils of Sahelanthropus tchadensis. Bent by millennia of interment, the skull had a deformed shape that made it tough to tag as totally human.

Now new fossil finds and a high-tech skull reconstruction (not shown) strongly suggest the species was human, after all. This would make it the oldest known human ancestor.
The breakthrough came when researchers recently discovered two new jawbones and a specialized tooth near the site of the original fossil find. A computer reconstruction revealed that these skull pieces fell into place when arranged along the lines of a human skull. Their alignment also hinted at a spine connection typical of upright-walking primates—in other words, humans and human ancestors.

The new findings, published today in the journal Nature, paint a picture of a somewhat chimp-bodied human ancestor that arose shortly after the chimpanzee and human lineages diverged.

Scientists Say,"Missing Link" Human Skull Found in Africa,

Scientists working in Africa have discovered a Stone Age skull that could be a link between the extinct Homo erectus species and modern humans.

The face and cranium of the fossil have features found in both early and modern human species. The skull is believed to be between 250,000 and 500,000 years old.

"[This skull] shows the continuity of the evolutionary record, so in that sense it is a link [between Homo erectus and modern humans]," said Scott Simpson, a paleontologist from Case Western Reserve University School of Medicine in Cleveland, Ohio.

Rare Find

Researchers discovered the skull five weeks ago at Gawis in Ethiopia's northeastern Afar region (map of Ethiopia). The area is rich in fossil and archaeological deposits ranging from 10,000 years to 5.6 million years in age.

An international group known as the Gona Paleoanthropological Research Project began field research in the area in 1999.

Asahmed Humet, a local Afar tribesman working with project, found the early-human cranium in a small gully at the base of a steep slope of sediments.

The skull was missing a lower jaw but had a nearly intact cranium. Most early human fossils are found in many small pieces.

The scientists believe the skull comes from the middle Pleistocene era, about 600,000 to 200,000 years ago.

Homo erectus is thought to be an ancestor of modern Homo sapiens. H. erectus first appeared in Africa and lived from about 1.9 to 0.8 million years ago.