Science and Medicine

Dinosaur Graveyard Reveals Oldest T. Rex Relative



Weighing only 10-15 pounds and about 4 feet in length from snout to tail tip, pint-sized Eodromaeus may be the oldest ancestor to date of all meat-eating dinosaurs, including T. rex. Illustration by Todd Marshall.

What may be the earliest known relative of T. rex and all meat-eating dinosaurs has been discovered. The dog-sized mini-predator would’ve made its future relatives proud as it fed on small dinosaurs and the young of other reptiles, and is now shaking up what scientists had previously learned about the evolution of those extinct giants.

The small, lanky, two-legged carnivore named Eodromaeus murphi—Eodromaeus being Greek for “dawn runner,” murphi in honor of field volunteer Jim Murphy—weighed only 10 to 15 lbs (4.5 to 6.8 kg) and measured about 4 ft (1.2 m) in length from snout to tail. The skeletons of two specimens were discovered side-by-side in 230-million-year-old iron-rich stone in the “Valley of the Moon” at the foothills of the Andes in northeastern Argentina, which was once the southwest corner of the supercontinent Pangaea.

“With a hike across the valley, you literally walk over the graveyard of the earliest dinosaurs to a time when they ultimately dominate,” said researcher Ricardo Martinez, a paleontologist at the National University of San Juan in Argentina.

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New Test Can Screen Couples for 448 Diseases



This testing is probably the way of the future

A new genetic test could soon allow couples to screen themselves for hundreds of recessive diseases to prevent them passing them on to their offspring.

American researchers reported the new test was capable of detecting 448 inherited conditions such as cystic fibrosis, fragile X syndrome and sickle-cell anemia.

The researchers, from the Drexel University College of Medicine in Philadelphia, said couples could be screened before conceiving so they could make informed reproductive choices thereafter.

For example, if a couple was told it had a 25 percent chance of having a baby with cystic fibrosis, they could opt to use sperm donation or in vitro fertilization to select unaffected embryos for implantation.

They could also have further screening during pregnancy at about 12 weeks with a view to abort an affected fetus. While such tests could significantly reduce the incidence of such diseases in the community, critics say they create unnecessary alarm about rare diseases and could lead to more abortions.

In a report on the finding in Science Translational Medicine, the researchers said their test would also be suitable to screen infants for treatable or preventable diseases where early diagnosis is beneficial.

The director of the Victorian Clinical Genetics Services, David Amor, said that although a similar genetic test to screen people for about 100 diseases became available on the Internet last year, this test represented a new and more powerful tool for accurately testing individuals for a very large number of recessive genes.

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How Do Brain Injuries like Gabrielle Giffords’ Heal?



“The bullet passes through the brain at such high velocity that it sends a shock wave to the brain,” Alexander said

It could take weeks to months to determine the extent of permanent damage from a brain injury like the one sustained by Rep. Gabrielle Giffords (D-Ariz.) in the tragic shooting that occurred Jan. 8 in Tucson, Ariz. So far, her doctors are optimistic—she can breathe on her own, and responds to verbal commands by wiggling her fingers and giving a thumbs up, and has shown movement on one side of her body, all of which are huge achievements this early in recovery.

Peter Rhee, the head of the University of Arizona Medical Center’s trauma unit where Giffords is being treated, said yesterday that she has a “101 percent chance of survival.”

But how does the brain patch itself up and regain function after a gunshot injury?

Two types of injuries typically occur with a gunshot to the head, Michael Alexander, a neurosurgeon and clinical chief of neurosurgery at Cedars-Sinai Medical Center in Los Angeles, told Life’s Little Mysteries. One is shear injury, caused as the bullet pierces the brain and tears tissue.

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