detritus
MM, NN
MM and NN are petrified nests of Henslow’s Sparrows (Centronyx henslowii). These pieces were found in the weedy woodlands of North-Eastern Illinois (MM in Thatcher Woods, River Forest and NN in the Middlefork Savanna Forest Preserve, Lake Forest). One of eleven highly vulnerable bird species of Cook County, Henslow’s Sparrow is also one of the estimated 389 North American bird species on the brink of extinction due to global warming, as reported by the National Audubon Society:
https://www.audubon.org/climate/survivalbydegrees