Sylvester Allred, a principal lecturer of biology at Northern Arizona University, will sign copies of his newly released book, The Natural History of the Tassel-eared Squirrel, from noon to 3 p.m. Thursday, April 28, in the NAU Bookstore.

Allred has dedicated his career to the teaching of biology with his research interest in the ecology of the tassel-eared squirrel and the ponderosa pine. His account includes brief biographies of the early naturalists who first described this squirrel, as well as descriptions of fossils and other remains that reveal the evolutionary history of these unique creatures.

He also will sign copies of his earlier works.

The event is free and open to the public.

For information, call (928) 523-7213.