MELISSA BLOCK, host:
This is ALL THINGS CONSIDERED from NPR News. I'm Melissa Block.
ROBERT SIEGEL, host:
And I'm Robert Siegel.
Nearly 2,000 years ago, a mysterious and advanced culture flourished in the Eastern and Midwestern United States. It's called the Hopewell tradition, and a new exhibition of artifacts is raising fresh questions about these ancient Americans.
From member station WNIN in Evansville, Indiana, Micah Schweizer reports.
MICAH SCHWEIZER: Workers building a road damage an ancient burial mound.
(Soundbite of music from film, "Raiders of the Lost Ark")
SCHWEIZER: An unexpected treasure trove of silver and copper pours from the ground.
(Soundbite of film, "Raiders of the Lost Ark")
SCHWEIZER: Only it's not a movie. The year is 1988, and the bulldozer operator digging in a southwest Indiana field decides to grab some of the treasure. He goes to prison for looting.
Just a few miles away, on a windswept day, more southwestern Indiana farmland - fields of corn-stalk stubble and gentle, rolling hills.
Ms. MICHELLE GREENAN (Archeologist): No. What youre seeing here is a complex of earthen structures that were very purposefully, and very specifically, built along this cultural landscape.
SCHWEIZER: Michelle Greenan is an archeologist and curator at the Indiana State Museum.
Ms. GREENAN: Theres a number of mounds here - probably 20; maybe even more -earthen architectural features that were built for different purposes.
SCHWEIZER: Like ceremonies or burial. This is called the Mann site, spelled M-A-N-N, named after the farmer who owned these sprawling, 500 acres. Two of the earthen structures are among the biggest mounds built anywhere by the Hopewell -not a tribe, but more of a way of life that flourished between about 150 and 450 C.E. The culture was named by archeologists in the 1800s.
Amateur archeologist Charlie Lacer began walking the Mann fields in the 1950s, collecting what he found.
Mr. CHARLIE LACER: You could find stuff that you could not find any other site around here. I mean, there is just tons of material there. You couldnt pick up everything you saw. You had to be kind of selective, particularly if youre carrying this stuff in your pockets.
SCHWEIZER: Lacer stuffed a lot into his pockets - 40,000 artifacts that he donated to the Indiana State Museum two years ago. Four hundred pieces are now on display in nearby Evansville - for the first time ever.
The exhibition is titled "Cherished Possessions: The Mann Hopewell Legacy of Indiana," but it was nearly called "Indianas Egypt."
(Soundbite of film, "Raiders of the Lost Ark")
Mr. HARRISON FORD (Actor): (As Indiana Jones) Archeology is the search for facts, not truths. If it's truth you're interested in, Dr. Tyrees philosophy class is right down the hall.
SCHWEIZER: In the end, the attempt at archeology a la Indiana Jones lost out to historical precision. But Michelle Greenan says the exhibitions almost-name gives a sense of the Mann sites importance.
Ms. GREENAN: Its a sleeping giant, and its going to take its place as one of the most important archeological sites in North America.
Mr. MIKE LINDERMAN: Its like Vegas for archeologists.
SCHWEIZER: Mike Linderman, who manages state historic sites in western Indiana, says the Mann site is bigger than the more famous Hopewell sites in Ohio, and its filled with even more exotic materials - like obsidian glass thats been traced to the Yellowstone Valley in Wyoming and with it, grizzly bear incisor teeth.
Mr. LINDERMAN: Grizzly bear, obviously, are not from southwestern Indiana, never have been. And theres a theory out there now that instead of being trade items, these items are actually being collected by the people from Mann site on rite-of-passage trips theyre taking out to the west.
You know, its something big if youve killed a grizzly bear, and you can bring its teeth back to Indiana.
SCHWEIZER: Jaguars and panthers arent from Indiana, either, but they show up as beautifully detailed carvings. Put them together with clay figurines that have slanted eyes - not a Hopewell feature - and Linderman says we could be looking at a connection between Indiana and Central or South America.
And this just scratches the surface, so to speak. In 2006, Staffan Peterson did the archeological version of an MRI scan of 100 acres at the site. Anytime his equipment detected an archeological feature, a dot showed up on a map.
Mr. STAFFAN PETERSON: And every day, wed download our data, and our jaws would drop. It was kind of like buckshot; there were so many. And we were able to map out upwards of 8,000 archeological features.
SCHWEIZER: Two of the most notable are what Peterson calls wood-henges - like Stonehenge, but made of wooden posts.
Mr. PETERSON: These things may be unique in the country.
SCHWEIZER: But there may be an even more remarkable discovery, one that could re-write history books. Mike Linderman says scientists are starting tests on what looks like evidence of lead smelting.
Mr. LINDERMAN: Lead is not known to have been processed or smelted in North America until the French arrive.
SCHWEIZER: About a thousand years after the Hopewell culture.
Mr. LINDERMAN: And if it can be proven that the people at Mann site were smelting lead, that would really, really be big news.
SCHWEIZER: Next, archeologists hope some targeted digs can answer at least a few of the Mann sites mysteries.
For NPR News, Im Micah Schweizer in Evansville, Indiana.
SIEGEL: And you can see some of those mysterious Hopewell artifacts, including the teeth of an ancient grizzly bear, at our website, npr.org.