Several of Dr. Sacks’ unusual interests are featured in David Coleman’s article in the New York Times, “In Praise of Early Adapters.” Particular attention is given to stromatolites and other ancient wonders.

Stromatolites, once thought to have been long extinct until a large living colony was discovered in Shark Bay in Western Australia in the mid-1950s, are made up of large colonies of bacteria, often blue-green algae, and sedimentary deposits, which grow naturally in a style that Dr. Sacks likened to a layer cake.

Maybe not the most appetizing cake, but he pointed out that stromatolites are held to be responsible for converting the abundance of carbon dioxide in the earth’s Archean-era atmosphere into oxygen. “Over the years, they made enough oxygen to make life possible for the rest of us,” he said.