Countless dinosaur bones lie buried in the rocks of South Dakota but the Christians excavating one remote cliff-face were digging not just for reptilian vertebrae but for the hand of God.
With screwdrivers, hammers and shaving brushes for tools, the group was seeking and, as far as it was concerned, unearthed proof that the animals perished not millions of years ago but in Noah's Flood circa 2300 BC.
To these believers in the Bible's literal truth, they are not dinosaurs but "missionary lizards", which are powerful weapons in the battle for young American hearts and minds.
Those certain that God made all living things, dinosaurs included, on Day Six of the Creation, are deploying ever more imaginative tactics in their struggle against schools and universities teaching Darwin's theory of evolution.
Boldest of all is a trend for believers, young and old, to dig for fossils and dinosaur remains as witness to God's handiwork.
Lecturing to a rapt audience of 20 like-minded Christians after a hard day in the field, Russ McGlenn, a self-styled amateur archaeologist and palaeontologist and head of Adventure Safaris, said: "Heavenly Father, we thank You for the evidence of a catastrophic flood event. We thank You for the time to study Your creation. Heavenly Father, we thank You for the evidence of a catastrophic flood event."
Mr McGlenn was admittedly preaching to the converted but his success at strengthening their beliefs and faith was undeniable.
"It's just dumb to believe that everything came from one kind of bang or fish or something," said Katy Carlson, 13, one of the youngest on the dig.
Her companions included a 74-year-old Californian woman who spends two weeks digging for dinosaurs every year, the mother of three teenagers who brought them there "as a Christmas present" and a group of Christian children from Wisconsin.
Camping outdoors, riding and simply marvelling at the emptiness of "Big Sky country" are all part of the fun but the main draw is the chance to get down on hands and knees and quarry for dinosaur remains.
South Dakota is one big open-air dinosaur cemetery. "Sue", the world's best preserved tyrannosaurus rex skeleton was discovered in the area and, in some locations, bones are easily spotted, poking through the soil. Just as evident, depending on who is looking, is "proof" that the creatures died in a flood. Evidence is seen in geological strata and the animals' sudden deaths.
The afternoon's work yielded a rich crop of bones, from a group of Edmontosauruses known to be buried in the hillside. The remains join similar exhibits, including a triceratops skull, at a museum opened by the land's owner to spread the word that Darwin was wrong.
"Dinosaur fossils are not proof of evolution but rather extinction," a poster tells visitors to the museum. The war between Darwinian science and Christian fundamentalists has raged for decades but the battleground has lately shifted from courtrooms and lecture halls to small-scale museums, churches and even a Creationist theme park called "Dinosaur Adventure Land".
According to the most recent poll, nearly half of all Americans, 48 per cent, believe in the Book of Genesis's version of our origins. The Creationists fervently hope that number may even be rising.
Evolution is "the dumbest and most dangerous idea in the history of humanity", said Kent Hovind, a vocal enthusiast for the cause who also runs the theme park in Florida. Explaining his Creationist creed, he said: "We think dinosaurs were part of the normal Creation and were just big lizards. Noah took some of them on the Ark, probably babies, when the floods came.
"Throughout history, there are stories of people killing the animals that survived but they called them dragons."
Passions aroused by the debate occasionally spill over into politics, usually into the charged sphere of education, sometimes involving national figures such as the former president Jimmy Carter and President George W Bush.