No, these weren’t otherworldly black monoliths and they weren’t for filming a sequel to “2001: A Space Odyssey” in La Plaza Cultural last Saturday afternoon. They were sculptures, by Toronto artist Ryan Legassicke, part of the installation “Shadows: Wall Disease.” There were five of them, life-sized representations of sections of walls “used to block access to public spaces.” Structures represented included the security fence used during the 2010 G20 Summit in Toronto; the Berlin Wall; the border fence between Nogales, Sonora, and Arizona; the Peace Lines wall in Belfast, Northern Ireland; and the Israeli separation barrier on the West Bank. The structures will be available for public viewing at MoRUS, at 155 Avenue C, from Oct. 16-26 (though it might be a bit hard to fit them in the radical museum). “The physicality of these walls, and the ideologies they represent, stand in stark contrast to the space around it, a historic community garden. The exhibition highlights the importance of continuing to work to preserve public spaces as free and open community places,” said Bill DiPaola, MoRUS co-director.