Natural history museums are so focused on the future that they have for centuries routinely preserved such specimens to answer questions they didn’t yet know how to ask, requiring methodologies that had not yet been invented, to make discoveries that would have been, for the original collectors, inconceivable.

THE people who first put gigantic mammoth and mastodon specimens in museums, for instance, did so mainly out of dumb wonderment. But those specimens soon led to the stunning 18th-century recognition that parts of God’s creation could become extinct. The heretical idea of extinction then became an essential preamble to Darwin, whose understanding of evolution by natural selection depended in turn on the detailed study of barnacle specimens collected and preserved over long periods and for no particular reason. Today, those same specimens continue to answer new questions with the help of genome sequencing, CT scans, stable isotope analysis and other technologies.

These museums also play a critical role in protecting what’s left of the natural world, in part because they often combine biological and botanical knowledge with broad anthropological experience. So when museum curators travel to a difficult habitat to conduct an environmental inventory, said Debra Moskovits of Chicago’s Field Museum, a team will typically work at the same time to understand the needs of surrounding communities.

After one such inventory in Ecuador, Dr. Moskovits stood up to withdraw from a meeting when it seemed as if an outsider should not be part of the discussion. The attendees told her to sit down again, saying: “You have no nationality. You are scientists. You speak for nature.” Just since 1999, according to the Field Museum, inventories by its curators and their collaborators have been a key factor in the protection of 26.6 million acres of wilderness, mainly in the headwaters of the Amazon.

It may be optimistic to say that natural history museums have saved the world. It may even be too late for that. But they provide one other critical service that can save us, and our sense of wonder: Almost everybody in this country — even children in Denver who have never been to the Rocky Mountains, or people in San Francisco who have never walked on a Pacific Ocean beach — goes to a natural history museum at some point in his life, and these visits influence us in deep and unpredictable ways.

Paul B. MacCready, for instance, became famous in the 1970s for building Gossamer Condor, the first successful human-powered aircraft, and then Gossamer Albatross, the first such craft to cross the English Channel. But growing up in New Haven, before engineering took hold of him, he used to visit the Yale Peabody Museum of Natural History to indulge a childhood obsession with winged insects. Years later, Dr. MacCready revisited the museum. One thing he still vividly recalled, in the aftermath of his triumphs, was an image on the wall of a diorama he came across, something between an entomological drawing and Breugel’s “Fall of Icarus”: It depicted a dragonfly on the wing, over a body of green water.

Maybe it was a trivial detail. Maybe most of our visits to natural history museums can seem trivial, just a way to pass Sunday afternoon with the family. But standing beneath the figure of Tyrannosaurus, or staring back at the skull of an early primate, or reliving the feats of Polynesian mariners, we dimly begin to understand the passage of time and cultures, and how our own species fits amid millions of others. We start to understand the strangeness and splendor of the only planet where we will ever have the great pleasure of living.