Berkeley geologists have uncovered compelling evidence that an asteroid impact on Earth 66 million years ago accelerated the eruptions of volcanoes in India for hundreds of thousands of years, and that together these planet-wide catastrophes caused the extinction of many land and marine animals, including the dinosaurs.
For 35 years, paleontologists and geologists have debated the role these two global events played in the last mass extinction, with one side claiming the eruptions were irrelevant, and the other side claiming the impact was a blip in a long-term die-off.
The new evidence includes the most accurate dates yet for the volcanic eruptions before and after the impact. The new dates show that the Deccan Traps lava flows, which at the time were erupting at a slower pace, doubled in output within 50,000 years of the asteroid or comet impact that is thought to have initiated the last mass extinction on Earth.
Both the impact and the volcanism would have blanketed the planet with dust and noxious fumes, drastically changing the climate and sending many species to an early grave.
“Based on our dating of the lavas, we can be pretty certain that the volcanism and the impact occurred within 50,000 years of the extinction, so it becomes somewhat artificial to distinguish between them as killing mechanisms: both phenomena were clearly at work at the same time,” said lead researcher Paul Renne, a UC Berkeley professor-in-residence of earth and planetary science and director of the Berkeley Geochronology Center. “It is going to be basically impossible to ascribe actual atmospheric effects to one or the other. They both happened at the same time.”
Link between tallness, higher cancer risk
Being tall is linked to a higher risk of cancer, especially for women, said research Thursday drawn from physical and health data for five million people in Sweden.
For every 10 centimetres (four inches) over one metre in height, the odds of developing cancer increased by 10 percent in men and 18 percent in women, the research team reported at a medical conference in Barcelona.
A Swedish woman 1.72 metres (six feet) tall, for example, was about a third more likely to contract cancer than a woman of 1.52 metres.
The findings, which have not been published in a scientific journal, support similar links found in other studies between height and elevated cancer risk—but the researchers said their work was based on the largest group of men and women yet.
But, the study is far from complete
It was not clear if their findings would translate to people who live in different climates, with different diets and genetic backgrounds.