A new study of sediments laid down shortly after an asteroid plowed into the Gulf of Mexico 65.5 million years ago, an event that is linked to widespread global extinctions including the demise of big dinosaurs, suggests that lowly worms may have been the first fauna to show themselves following the global catastrophe. (more…)
A battle that brews in the mother’s womb between the father’s biological goal to produce the biggest, healthiest baby possible vs. the mother’s need to live through delivery might help explain preeclampsia, an often deadly disease of pregnancy. The fetus must be big enough to thrive, yet small enough to pass through the birth canal. In a new study, Yale researchers describe the mechanism that keeps these conflicting goals in balance. (more…)
*A slight change in molecular structure introduced by genetic engineering gives crop-protecting proteins called Bt toxins a new edge in overcoming resistance of certain pests, a UA-led team of researchers reports in Nature Biotechnology.*
One of the most successful strategies in pest control is to endow crop plants with genes from the bacterium Bacillus thuringiensis, or Bt for short, which code for proteins that kill pests attempting to eat them.
But insect pests are evolving resistance to Bt toxins, which threatens the continued success of this approach. In the current issue of Nature Biotechnology, a research team led by UA Professor Bruce Tabashnik reports the discovery that a small modification of the toxins’ structure overcomes the defenses of some major pests that are resistant to the natural, unmodified Bt toxins. (more…)
AUSTIN, Texas — Chagas disease, a tropical parasitic disease that can lead to life-threatening heart and digestive disorders, may be more widespread in Texas than previously thought, according to research from The University of Texas at Austin.
“We’ve been studying this for four years now, and this year the number of disease-causing insects is quite amazing,” says Sahotra Sarkar, professor of integrative biology and philosophy at The University of Texas at Austin and lead author of a paper on the disease published in PLoS Neglected Tropical Diseases. (more…)
The long-standing consensus of why insects stick together after mating has been turned on its head by scientists from the University of Exeter.
Published in Current Biology, their study shows that, contrary to previous thinking, females benefit from this arrangement just as much as males.
Instead of dominating their female partners through bullying and aggressive behaviour, males were revealed to be protective, even laying their lives on the line when their mates faced danger.
Previously, scientists assumed that male insects stay close to females after mating to stop them from taking other partners. Female insects have multiple mates and the last mate is most likely to fertilise her eggs. Therefore, by preventing females from taking other mates a male is most likely to father her offspring. (more…)
Charles P. Sonett, the first head of the UA’s department of planetary sciences, died at the age of 87. Sonett was involved in spacecraft missions that dramatically advanced our understanding of the solar system and beyond, including the Pioneer Program, the Explorer Program and the Apollo Program
Charles “Chuck” P. Sonett, a founding faculty member and the first department head of the University of Arizona’s department of planetary sciences, died on Sept. 30. He was 87. (more…)
The brain learns through changes in the strength of its synapses — the connections between neurons — in response to stimuli.
Now, in a discovery that challenges conventional wisdom on the brain mechanisms of learning, UCLA neuro-physicists have found there is an optimal brain “rhythm,” or frequency, for changing synaptic strength. And further, like stations on a radio dial, each synapse is tuned to a different optimal frequency for learning.
The findings, which provide a grand-unified theory of the mechanisms that underlie learning in the brain, may lead to possible new therapies for treating learning disabilities. (more…)
PASADENA, Calif. — Astronomers have found a new cosmic source for the same kind of water that appeared on Earth billions of years ago and created the oceans. The findings may help explain how Earth’s surface ended up covered in water. (more…)
