Digging into natural sciences

Natural sciences seem to have a natural appeal to children.

It’s something members of the River Valley Rockhounds encourage.

“Any kid likes rocks – rocks and dinosaurs,” said Robert Wolf, president of the club. “We’re a little short on dinosaurs in Iowa, but we have plenty of interesting rocks and fossils.”

Samples of those rocks, fossils, gems and jewelry will be on display during the 51st annual show by the River Valley Rockhounds 9 a.m. to 5 p.m. Saturday and 11 a.m. to 4 p.m. Sunday at the east campus of Iowa Central Community College.

The show will include displays, dealers and free samples for children. Admission is $1 for an individual or $2 for a family.

While the appeal of a rock and fossil show to children seems to be innate, interest in geology among adults tends to be a bit more superficial.

“If they don’t know about minerals and rocks, it’s the color that catches their eye,” Wolf said.

Though not brightly colored, an 85-pound lycopod specimen likely to catch quite a few glances will be on display at the show.

Wolf discovered it along the Des Moines River bluffs in the Kalo area six to eight years ago.

A lepidodendron is an extinct, primitive tree-like plant that grew up to 100 feet tall with trunks that were more than three feet in diameter. They also had a very distinct scale-patterned bark and seed pods that looked like pine cones.

According to palaeontologists, the plants thrived approximately 310 million years ago and were common in the coastal swamps that ultimately created the coal deposits in the state.

The lepidodendron are related to evergreen ground pines and club mosses, some species of which can still be found in Iowa today.

The fossil Wolf found is actually a cast of the stigmaria or root section.

The organic matter of the root decayed away long ago, he said, but its form was left in the surrounding material in such a defined manner that surface details of the root and its off-shoots or rootlets are visible.

What makes the specimen truly unique is that the rootlets are intact rather than being ripped away and disturbed before the fossil could form.

It is estimated the lepidodendron became extinct 220

million years ago when a mass extinction of plants and marine life occurred.

What prompted the extinction remains uncertain, Wolf said. Theories on its cause include climate change, glacier activity or even an asteroid impact.

“They’re still working on those ideas,” Wolf said.

What is certain is that Iowa is full of fossils, mostly those of amphibian and marine animals since the area was covered by an ancient ocean.

“A lot of people don’t realize Iowa has a lot to offer,” Wolf said. “They think you have to go out west.”

Wolf began his own life-long fossil hunting pastime when he was in fourth grade. A friend showed him a fossil he had found in the crushed rock used in the drive way. Intrigued, the two went looking among the rocks in a nearby field and from there “got hooked.”

Wolf’s collection now numbers well beyond 17,000 specimens, many of which he hasn’t yet catalogued.

“It’s like having a piece of another world,” he said.

The public, whether knowledgeable in geology or simply enamoured with the shimmer and shine of gem stones, will get a chance to not only obtain their own other-worldly rock or fossil at the show, they may also find a new perspective.

“I hope they leave with a new appreciation for nature and what it has to offer,” Wolf said. “Hopefully the kids will open their eyes and look around and notice what can be found in the natural world.”