In 1971 when Nicholas Swearer began work on the iguana that would become known as Iggy, mascot of the Science Museum of Minnesota, he was only 15 years old. He modeled the sculpture after his pet iguana, Spot, and spent four years and 12,500 railroad spikes creating the 3,900-pound sculpture. When Swearer left for college his parents sold the sculpture for $10,000 to collectors who donated it to the Science Museum in 1978.

Iggy guarded the Science Museum entrance until 1999 when the museum moved to its current location on Kellogg Boulevard. Iggy moved with the museum, but first took a tour around the Twin Cities and was restored and cleaned. He currently stands in front of the bus drop off at the back side of the museum.