Category Archives: Science

Pistil leads pollen in life-and-death dance

Pollination, essential to much of life on earth, requires the explosive death of the male pollen tube in the female ovule. In new research, Brown University scientists describe the genetic and regulatory factors that compel the male’s role in the process. Finding a way to tweak that performance could expand crop cross-breeding possibilities.

PROVIDENCE, R.I. [Brown University] — Millions of times on a spring day there is a dramatic biomolecular tango where the flower, rather than adorning a dancer’s teeth, is the performer. In this dance, the female pistil leads, the male pollen tubes follow, and at the finish, the tubes explode and die. A new paper in Current Biology describes the genetically prescribed dance steps of the pollen tube and how their expression destines the tube for self-sacrifice, allowing flowering plants to reproduce. (more…)

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From flounders to seahorses: Evolutionary success of spiny-rayed fishes detailed

Even as the dinosaurs were becoming extinct 66 million years ago, the ancient ancestor of spiny-rayed fishes flourished, eventually giving rise to tens of thousands of species that can now be found in home aquariums or on dinner plates. Using modern genetic tools and information from the fossil record, a team led by researchers at Yale University, University of Oxford, and University of California-Davis have constructed a detailed evolutionary history of the 18,000 species of spiny-rayed fishes existing today, a diverse group that includes basses, pufferfishes, and cichlids, and that comprises a large portion of the vertebrate tree of life.

The findings published the week of July 15 in the Proceedings of the National Academy of Sciences show surprisingly close evolutionary relationships between lineages of fish species such as tunas and seahorses, and suggest some fish lineages — like cichlids, the tiny gobies, and little-studied snailfishes — are experiencing high rates of new species origination. (more…)

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Rain Gods in a Desert Sea: New Book Celebrates Southern Arizona’s Mountains

A book by two UA scientists explains the story behind the scenery of the “sky islands,” the unique mountain ranges dotting southern Arizona and northern Sonora, Mexico

University of Arizona scientists Wendy Moore and Richard Brusca have published an illustrated book to celebrate and share the rich and unique natural history of southern Arizona’s mountains – the “sky islands” – with a general, non-scientific audience.   (more…)

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Expressly Unfit for the Laboratory

Berkeley Lab Researchers Find Little Correlation Between Microbial Gene Expression and Environmental Conditions in the Laboratory

A new study challenges the orthodoxy of microbiology, which holds that in response to environmental changes, bacterial genes will boost production of needed proteins and decrease production of those that aren’t. Researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) found that for bacteria in the laboratory there was little evidence of adaptive genetic response. In fact, most bacterial genes appear to be regulated by signals unrelated to their function. (more…)

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Noble gases hitch a ride on hydrous minerals

The six noble gases do not normally dissolve into minerals, leaving earth scientists to wonder how they are subducted back into the Earth. Researchers at Brown have discovered that the lattice structure of minerals such as amphibole provides a way. Better yet, the multiple isotopes of noble gases could help scientists track volatiles like water and carbon. (more…)

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Cosmochemist discovers potential solution to meteorite mystery

Chondrules may have formed from high-pressure collisions in early solar system

At issue is how numerous small, glassy spherules had become embedded within specimens of the largest class of meteorites—the chondrites. British mineralogist Henry Sorby first described these spherules, called chondrules, in 1877. Sorby suggested that they might be “droplets of fiery rain” which somehow condensed out of the cloud of gas and dust that formed the solar system 4.5 billion years ago. (more…)

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‘Life as Research Scientist’: Angel Byrd, Cell Biologist

For years, Brown University M.D./Ph.D. student Angel Byrd had dedicated herself to studying how immune system cells capture invading fungal pathogens. Like those cells, called neutrophils, she had seized on seemingly every opportunity that had come her way. (more…)

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