Life originated in ‘little ponds’

HOW did life on Earth begin? A study out yesterday backs the theory that meteorites splashing into warm ponds leached essential elements that gave rise to the building blocks of life billions of years ago.

The report is based on “exhaustive research and calculations” in astrophysics, geology, chemistry and biology, according to a summary provided by McMaster University.

“Because there are so many inputs from so many different fields, it’s kind of amazing that it all hangs together,” co-author Ralph Pudritz, of the McMaster’s Origins Institute and its department of physics and astronomy, said.

“Each step led very naturally to the next. To have them all lead to a clear picture in the end is saying there’s something right about this.”

The life-giving potential of these socalled “warm little ponds” was raised by the famed biologist Charles Darwin, who developed the theory of evolution, in a letter to a friend in 1871.

“But if (and oh what a big if) we could conceive in some warm little pond with all sorts of ammonia and phosphoric salts, light, heat, electricity et cetera present, that a protein compound was chemically formed, ready to undergo still more complex changes,” he wrote at the time.

Since then, researchers have debated whether life emerged in ponds, or in hydrothermal vents along the ocean floor.

The latest study finds ponds were far more likely, because a cycle from wet to dry was needed to bond basic molecular building blocks in the ponds into self-replicating ribonucleic acid (RNA) molecules.

These RNA molecules constituted the first genetic code for life on the planet, and came before DNA, said the findings.

“In order to understand the origin of life, we need to understand Earth as it was billions of years ago,” co-author Thomas Henning, from the Max Planck Institute for Astronomy, said.