choice when asking about the prevalence of intelligent life in the cosmos. But paleontology, the study of ancient life, is a good place to start when asking profound philosophical questions about the evolution of life here on our own planet and elsewhere.

To that end, at least one prominent evolutionary biologist, who has devoted his career to studying the fossils of extinct marine invertebrates, says that while life itself may be common off world, intelligent life —- particularly of the sort that can build radio telescopes and spaceships —- is likely to be very rare indeed.

The number of highly intelligent species on earth represents an incredibly small percentage compared to the total number of species, Bruce Lieberman, the book’s co-author, and an evolutionary biologist and paleontologist at the University of Kansas in Lawrence, told me via email. It took more than 100,000 years for our species to be able to develop the technology to build spaceships, he said. Thus, the development of species that could create complex technologies seems extremely rare, Lieberman told me.

That doesn’t mean that the onset of life here was a surprise, nor should it be elsewhere.

Based on what we know of the fossil record here, life should be extremely common, said Lieberman. But the evolution of complex life on this planet took a long time to happen, about 2 billion years if we treat that as the origin of the eukaryotic cell (a cell with a membrane-bound organelles), he said. It then took another 1.4 billion years from that point to the origin of animals, said Lieberman. This makes me think that complex life should be rare, he said.

That’s a refrain that’s often repeated by Lieberman and co-author American Museum of Natural History paleontologist Niles Eldredge, in their new book, Macroevolutionaries: Reflections on Natural History, Paleontology, and Stephen Jay Gould.

“Macroevolutionaries” is in part an homage to Lieberman’s former mentor and Eldredge’s colleague, the late Harvard University paleontologist Stephen J. Gould who had a remarkable ability to turn a phrase.

“Wind back the tape of life to the early days of the Burgess Shale; let it play again from an identical starting point, and the chance becomes vanishingly small that anything like human intelligence would grace the replay,” Gould noted in his 1997 book, “Wonderful Life: The Burgess Shale and the Nature of History.”

“Macroevolutionaries” takes a look back both at Gould’s work on the history of evolution here on earth and its relation to the broader cosmos. Read More at https://www.forbes.com/sites/brucedorminey/2025/01/08/intelligent-life-in-cosmos-is-likely-very-rare-says-paleontologist/