On November 24 this year, Darwin’s acclaimed contribution to science, The Origin of Species, will complete 150 years of publication. While Darwin proposed the theory of natural selection, there were some significant questions that puzzled Darwin and answers to which were found only six decades ago. Prof J. William Schopf, the man credited with finding answers to ‘Darwin’s Dilemma’ in the 1960s, delivered a lecture at ‘Evolution—Life’s Continuum’, a conclave organised by the Birbal Sahni Institute of Paleobotany, Lucknow, to celebrate 150 years of The Origin of Species and 200 years of Darwin’s birth.

“Larger parts of Darwin’s theory were substantiated by the presence of fossils. However, the most ancient fossil known to him was of trilobites—extinct invertebrate marine animals—which existed in the early Cambrian Period (around 540 million years ago). Before this, rocks showed no trace of life. Darwin knew that trilobites were far too complicated to have anything to do with the origin of life,” Prof Schopf told The Sunday Express.

“For a century, many attempts were made to solve the dilemma but with little success, because no one asked the right question,” said Prof Schopf, a paleobiologist at the University of California. “Geologists were looking for large fossils before the Cambrian period but did not find anything because in the pre-Cambrian age existed in microscopic forms,” said Prof Schopf, who also believes that after Drawin, the question was never pursued seriously because it was considered more of a religious question than a scientific one.

“The first man to peep into life in the pre-Cambrian age was Charles D. Walcott, who discovered stromatolites (dome shaped mega structures formed in water by microscopic organisms) in 1883. But it was only 70 years later that geologist Stanley Tyler stumbled upon stromatolites 1,900 million years old,” said Schopf. “He contacted Elso Barghoon, a biologist of Harvard University, to understand the fossils and realised they were formed by microscopic organisms which were fossilised in the stromatolites.”

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