He helped excavate thousands of ice age fossils, including mammoths, mastodons, camels, plants and insects, at the site of a reservoir expansion in Snowmass Village, Colo. And in the Denver suburbs, at two separate construction sites, one for a police and fire station and another for an assisted living facility, workers turned up horned dinosaur remains.
“I put together huge expeditions around the country to go out and spend eight weeks digging in remote field areas, looking for things like horned dinosaurs,” Dr. Sertich said. “And it turns out that some of those finds are sitting right in our own backyards.”
In Hot Springs, S.D., work on a housing development stopped abruptly in the 1970s when workers found the skeleton of a mammoth. When Jim I. Mead and other paleontologists went there and started digging, they found another skeleton, and then another. The site, Dr. Mead said, turned out to be a long-ago sinkhole pond where mammoth after mammoth drowned after finding itself unable to climb out. The housing developer agreed to stop building, and decades later, mammoths are still being uncovered there.
“We’re totally lucky,” said Dr. Mead, now the director of research at the Mammoth Site, which hosts tourists, school groups and scientists. “It’s just phenomenal that this person said, ‘I want this to be preserved.’”
There can sometimes be tension between science and construction. Unlike with human remains and Native American cultural artifacts, there is often no legal requirement in the United States to report paleontological finds on privately owned land, meaning that some animal bones end up being plowed over or sold to private collections instead of turned over for study. And given the tight deadlines facing many construction projects, calling in scientists can be seen as an expensive diversion from the task at hand.
Earlier this year in Utah, construction equipment damaged a set of rare dinosaur footprints on federal land, bringing criticism that paleontologists had not been more involved in supervising the site.