A couple of articles that caught my attention this week, both about beginnings.
First, another note on that old conundrum, where did life originate?
No one, to my knowledge, has made a case for this being an either/or question. I've already explored some of the possibilities, and while this finding adds support to the "it came from outer space" theory, it doesn't address the "it came from the deeps" theory. I, for one, see absolutely no reason why it couldn't have been both.
The other "origins" article hits a little closer to home: when and where did modern humans originate? It's not as recently as we had thought:
Once again, we have a rather ambiguous question: the evidence from mitochondrial DNA is pretty definitive that we all descended from a small group of women living in East Africa about 200,000 years ago -- but that doesn't really address where and when the ancestors of those women originated.
It all comes down to asking the right questions.
First, another note on that old conundrum, where did life originate?
Scientists believe that, along with the rest of our solar system, Earth arose from material left over after the Sun was formed. But how living organisms came about is a matter for debate. As Wired points out, one theory holds that life came about on Earth independently from the Sun, after the planet was formed. The other states that the ingredients of life were were formed in a solar nebula and then arrived on Earth via comets. "The detection of this molecule points toward the latter theory," Rafael Martín-Doménech, one of the leaders of Centro de Astrobiología, told Wired.
No one, to my knowledge, has made a case for this being an either/or question. I've already explored some of the possibilities, and while this finding adds support to the "it came from outer space" theory, it doesn't address the "it came from the deeps" theory. I, for one, see absolutely no reason why it couldn't have been both.
The other "origins" article hits a little closer to home: when and where did modern humans originate? It's not as recently as we had thought:
According to the textbooks, all humans living today descended from a population that lived in east Africa around 200,000 years ago. This is based on reliable evidence, including genetic analyses of people from around the globe and fossil finds from Ethiopia of human-like skeletal remains from 195,000–165,000 years ago.
Now a large scientific team that I was part of has discovered new fossil bones and stone tools that challenge this view. The new studies, published in Nature, push back the origins of our species by 100,000 years and suggest that early humans likely spanned across most of the African continent at the time.
Once again, we have a rather ambiguous question: the evidence from mitochondrial DNA is pretty definitive that we all descended from a small group of women living in East Africa about 200,000 years ago -- but that doesn't really address where and when the ancestors of those women originated.
It all comes down to asking the right questions.
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