The discovery of a single anatomical difference between males and females of a species of Stegosaurus provides some of the most conclusive evidence that some dinosaurs looked different based on sex, according to new research.
Princeton University research published in the journal PLoS ONE found that the back plates of the species Stegosaurus mjosi came in two varieties that indicated the animal’s sex — short and wide, and tall and narrow. Females had one type of plate and males donned the other. The lack of a particular female-specific bone tissue found in birds and some dinosaurs, however, made it difficult to determine which sex had which plate type.(more…)
As California finally experiences the arrival of a rain-bearing Pineapple Express this week, two climate scientists from the University of Minnesota and Woods Hole Oceanographic Institution have shown that the drought of 2012-2014 has been the worst in 1,200 years. (more…)
The Yarlung-Tsangpo River in southern Asia drops rapidly through the Himalaya Mountains on its way to the Bay of Bengal, losing about 7,000 feet of elevation through the precipitously steep Tsangpo Gorge.
For the first time, scientists have direct geochemical evidence that the 150-mile long gorge, possibly the world’s deepest, was the conduit by which megafloods from glacial lakes, perhaps half the volume of Lake Erie, drained suddenly and catastrophically through the Himalayas when their ice dams failed at times during the last 2 million years. (more…)
Analysis of the Last Glacial Maximum sheds light on climate models’ ability to simulate tropical climate change
How will rainfall patterns across the tropical Indian and Pacific regions change in a future warming world? Climate models generally suggest that the tropics as a whole will get wetter, but the models don’t always agree on where rainfall patterns will shift in particular regions within the tropics.
A new study, published online May 19 in the journal Nature Geoscience, looks to the past to learn about the future of tropical climate change, and our ability to simulate it with numerical models. (more…)
PASADENA, Calif. – Detailed analysis and review have borne out researchers’ initial interpretation of pebble-containing slabs that NASA’s Mars rover Curiosity investigated last year: They are part of an ancient streambed.
The rocks are the first ever found on Mars that contain streambed gravels. The sizes and shapes of the gravels embedded in these conglomerate rocks — from the size of sand particles to the size of golf balls — enabled researchers to calculate the depth and speed of the water that once flowed at this location. (more…)
While astronomers now know that exoplanets are exceedingly common in the galaxy, the mechanics by which they are formed aren’t well understood. Planetary childhood remains a mystery.
Young stars start out with a massive disk of gas and dust that over time, astronomers think, either diffuses away or coalesces into planets and asteroids.
“The speculation is that as planets form they clear out a region of gas and dust around them, forming a telltale ‘gap’ in the disk”, said Stefan Kraus, from Physics and Astronomy at the University of Exeter. (more…)
A roughly 3.5-mile high Martian mound that scientists suspect preserves evidence of a massive lake might actually have formed as a result of the Red Planet’s famously dusty atmosphere, an analysis of the mound’s features suggests. If correct, the research could dilute expectations that the mound holds evidence of a large body of water, which would have important implications for understanding Mars’ past habitability.
Researchers based at Princeton University and the California Institute of Technology suggest that the mound, known as Mount Sharp, most likely emerged as strong winds carried dust and sand into the 96-mile-wide crater in which the mound sits. They report in the journal Geology that air likely rises out of the massive Gale Crater when the Martian surface warms during the day, then sweeps back down its steep walls at night. Though strong along the Gale Crater walls, these “slope winds” would have died down at the crater’s center where the fine dust in the air settled and accumulated to eventually form Mount Sharp, which is close in size to Alaska’s Mt. McKinley. (more…)
UCLA researchers have used a brain-imaging tool and stroke risk assessment to identify signs of cognitive decline early on in individuals who don’t yet show symptoms of dementia.
The connection between stroke risk and cognitive decline has been well established by previous research. Individuals with higher stroke risk, as measured by factors like high blood pressure, have traditionally performed worse on tests of memory, attention and abstract reasoning. (more…)
