WASHINGTON, D.C. - The Obamas are decorating their private spaces with more modern and abstract artwork than has ever hung on the White House walls. Pieces by contemporary African-American and Native American artists are on display. Historical works by George Catlin and artifacts such as a steamboat paddlewheel patent model now sit in the Oval Office. Works by big name modern artists – Jasper Johns and Mark Rothko – are rubbing shoulders with lesser-known artists such as Alma Thomas, an abstract painter from the 1960s and 1970s.