When the ArtCars go on parade, you can’t miss artist Jan Elftmann’s “Cork Truck”— it’s a whimsical marvel. With the exception of its windows, tires and headlights, the whole vehicle is artfully encrusted with the thousands upon thousands of wine and champagne corks she collected for more than a decade.

Tomorrow evening, for the art-and-science “Beaker and Brush” lecture series, this eccentric artist and educator will participate in a discussion about “why we collect.” Joining her will be Jackie Hoff, director of Collections Services in the Science Learning Division, one of those responsible for the care, conservation and cataloging of artifacts in the Science Museum.

Specifically, the evening’s conversation will center on that peculiar alchemy — of innate disposition, memory and idiosyncratic determinations of value — which turns interest into something more obsessive. What is it that incites and sustains a collector’s zeal? It’s a fascinating question, whether you’re talking about a fancier’s pursuit of stamps or porcelain bunnies, Happy Meal toys or fine art. For her own part, Elftmann has had the magpie bug as long as she can remember; she claims to have been “collecting, sorting and organizing objects since she was born.” Beyond the 10,000-some corks she gathered and glued to the “Cork Truck,” recently, she’s turned her hand to “painting” both lawn ornaments and taxidermy critters with various objects she’s found, collected and sorted by color.

Beyond the individual’s drive to hunt and gather, the night’s discussion will address larger, related concerns about the process of determining value for various collectibles and the nuanced decision-making involved with institutional acquisition, curation, presentation and preservation of objects held in public trust.

When you think about it, what we choose to preserve and keep close, as individuals and as societies, amounts to nothing less than a declaration of who we are. Our collections serve as talismans of identity and memory, offering a shorthand by which to tell each other (and ourselves) our life stories. It’s fantastic fodder for an evening’s conversation, don’t you think?

“Why We Collect,” a discussion in the “Beaker and Brush” monthly lecture series about the intersection of art and science, co-sponsored by the Science Museum of Minnesota and the Saint Paul Art Crawl; this event will take place Tuesday, April 10, from 6:30 to 8:30 p.m., at Amsterdam Bar & Hall, 6 W. Sixth St., St. Paul, Minn. Admission is free and open to the public. Find more information online: http://www.smm.org/beakerandbrush