The Origins of Life

A mineralogist believes he’s discovered how life’s early building blocks connected four billion years ago

A fossil collector since childhood, Bob Hazen has come up with new scenarios for life's beginnings on earth billions of years ago. (Amanda Lucidon)
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After taking a paleontology class together at the Massachusetts Institute of Technology, Hazen and Margee Hindle, his future wife, started collecting trilobites. They now have thousands. “Some of them are incredibly cute,” says Hazen. “This bulbous nose—you want to hug them.”

There are trilobites all over Hazen’s office and a basement guest room at the Hazens’ Bethesda, Maryland, home—they cover shelves and fill desk drawers and cabinets. There’s even trilobite art by his now grown children, Ben, 34, who is studying to be an art therapist, and Liz, 32, a teacher. “This is the ultimate cute trilobite,” he says, reaching into a cabinet and taking out a Paralejurus. “How can you not love that?”

Hazen calls himself a “natural collector.” After he and Margee bought a picture frame that just happened to hold a photograph of a brass band, they started buying other pictures of brass bands; eventually they wrote a history of brass bands—Music Men—and a time in America when almost every town had its own. (Bob has played trumpet professionally since 1966.) He has also published a collection of 18th-and 19th-century poems about geology, most of which, he says, are pretty bad (“And O ye rocks! schist, gneiss, whate’er ye be/Ye varied strata, names too hard for me”). But the couple tend not to hold on to things. “As weird as this sounds, as a collector, I’ve never been acquisitive,” Bob says. “To have been able to hold them and study them up close is really a privilege. But they shouldn’t be in private hands.” Which is why the Hazen Collection of Band Photographs and Ephemera, ca. 1818-1931, is now at the National Museum of American History. Harvard has the mineral collection he started in eighth grade, and the Hazens are in the process of donating their trilobites to the National Museum of Natural History.

After considering, for some time, how minerals may have helped life evolve, Hazen is now investigating the other side of the equation: how life spurred the development of minerals. He explains that there were only about a dozen different minerals—including diamonds and graphite—in dust grains that pre-date the solar system. Another 50 or so formed as the sun ignited. On earth, volcanoes emitted basalt, and plate tectonics made ores of copper, lead and zinc. “The minerals become players in this sort of epic story of exploding stars and planetary formation and the triggering of plate tectonics,” he says. “And then life plays a key role.” By introducing oxygen into the atmosphere, photosynthesis made possible new kinds of minerals—turquoise, azurite and malachite, for example. Mosses and algae climbed onto land, breaking down rock and making clay, which made bigger plants possible, which made deeper soil, and so on. Today there are about 4,400 known minerals—more than two-thirds of which came into being only because of the way life changed the planet. Some of them were created exclusively by living organisms.

Everywhere he looks, Hazen says, he sees the same fascinating process: increasing complexity. “You see the same phenomena over and over, in languages and in material culture—in life itself. Stuff gets more complicated.” It’s the complexity of the hydrothermal vent environment—gushing hot water mixing with cold water near rocks, and ore deposits providing hard surfaces where newly formed amino acids could congregate—that makes it such a good candidate as a cradle of life. “Organic chemists have long used test tubes,” he says, “but the origin of life uses rocks, it uses water, it uses atmosphere. Once life gets a foothold, the fact that the environment is so variable is what drives evolution.” Minerals evolve, life arises and diversifies, and along come trilobites, whales, primates and, before you know it, brass bands.

Helen Fields has written about snakehead fish and the discovery of soft tissue in dinosaur fossils for Smithsonian. Amanda Lucidon is based in Washington, D.C.


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