SCIENTISTS ARE RETHINKING WHERE LIFE ORIGINATED ON EARTH
Rather than springing up from the sea, the first biological cells may have formed on
land, Nature reports. Water is essential
to life, but it also breaks apart molecules like DNA and proteins, a paradox
that has long puzzled scientists. Although chemists have created key components
of cells by hitting chemical-based chemicals with ultraviolet (UV) radiation
and subjecting them to dry and wet cycles, they have been unable to produce the
same effects in seawaterlike conditions. Instead, researchers propose, life may
have formed on bodies of water on land—perhaps formed by craters, like the
Manicouagan Reservoir (above)—where there was intermittent availability of
water as well as enough UV radiation from sunlight.
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