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Shaken family tree

Field Museum in Chicago (Antonio Perez/Chicago Tribune via AP)

Science

Shaken family tree

After decades, some scientists offer T. rex new relatives

Some evolutionary scientists want to boot Tyrannosaurus rex out of his place on the dinosaur family tree.

In March researchers from the University of Cambridge and the Natural History Museum in London published an article in Nature proposing that dinosaur groupings on the evolutionary tree need to be reworked. The proposal is a shock to evolutionary biologists who have trusted in the dinosaur tree for well over a century, but it illustrates how so much of evolutionary science involves guesswork.

Until now scientists have divided dinosaurs into two groups: bird-hipped dinosaurs, including the armored Stegosaurus, and lizard-hipped dinosaurs, including theropods like T. rex and sauropods like Brontosaurus. Many evolutionary scientists have long believed theropods evolved into birds, but that has been confusing since theropods are in the lizard-hipped family.

Citing skeletal similarities, the U.K. researchers now propose theropods be moved to the bird-hipped group, a position more favorable to the dino-to-bird hypothesis.

The proposed change, if widely adopted, could upset museum displays around the world. It is also an important point in the creation/evolution debate, according to Jerry Bergman, a biology professor at Northwest State Community College in Ohio.

Evolutionary scientists base their tree on a wrong assumption—that all living organisms evolved from a common ancestor—and must tweak any new evidence to fit their theory, Bergman said. If the theory says theropods evolved into birds, it makes more sense if you can tweak theropods into the bird-hipped group: “Eventually you tweak it so much the whole thing falls apart.”

Bergman believes the huge variety of dinosaurs, some gigantic like T. rex, others not much bigger than a dog, support the view that God created animals by their kinds. “The tree hypothesis can’t explain that kind of diversity,” he said. “When you look at the world through Darwinian glasses … that is all you are going to see.”

Sweet solution

Antibiotics are necessary to fight infections, but their use is spurring the growth of superbugs. Now researchers at McGill University have discovered a way to enhance the potency of antibiotics and decrease the required dosages—by adding a maple syrup extract.

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Syrup (Handout)

The researchers separated phenolic compounds, the chemicals that give maple syrup its golden color, from water and sugar in the syrup. When they mixed the phenolic extract with two commonly used antibiotics, the antibiotics had the same bacteria-killing effect with 90 percent smaller dosages. The approach, tested on mice, worked on a variety of bacterial strains, including E. coli and Proteus mirabilis, which causes urinary tract infections.

The researchers presented their work at a recent meeting of the American Chemical Society. —J.B.

Getting their nerve

Tufts University researchers have developed a treatment that could help transplanted sensory organs regrow needed nerve connections. The development came, oddly enough, by grafting eyes on the tails of blind tadpoles. For the study, published in npj Regenerative Medicine in March, the scientists grafted eyes onto the tails of blind tadpoles, then treated them with a neurotransmitter drug.

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Tadpole with eye graft on tail (Handout)

Neurotransmitters are chemical messengers that transmit nerve signals from cell to cell. The tadpoles treated with the drug grew a significantly increased supply of nerves to the grafted eyes. They were also 18 percent more likely to distinguish red from blue and to follow rotating optical patterns compared with eye-grafted tadpoles not treated with the drug. —J.B.