Poop Reveals an immigrant in Isle Royale Wolves' gene pool

The large, lighter colored wolf in the center is the immigrant from Canada to Isle Royale dubbed The Old Gray Guy. The wolf to the left is his daughter and mate, who died during 2010. (Photo © and courtesy John Vucetich. Reprinted with permission.)

By Jennifer Donovan, Michigan Tech Director of Public Relations
Posted March 30, 2011, in the Michigan Tech News

HOUGHTON -- In a journal article published online on March 30, 2011, in the Proceedings of the Royal Society and in their 2010-2011 annual report on the Wolves and Moose of Isle Royale, Michigan Technological University researchers John A. Vucetich and Rolf O. Peterson tell an unexpected tale of genetic immigration.

In 1997, a virile male wolf crossed an ice bridge from Canada to the remote island national park in northern Lake Superior. He was physically larger than most Isle Royale wolves; and soon after his arrival he became the alpha male of Middle Pack, one of the island’s three packs. As he aged, his fur turned very light, a trait that had not been seen previously on Isle Royale, but has since become common. Before knowing his genetic history, the researchers called this wolf "The Old Gray Guy."

How did Vucetich and Peterson learn so much about The Old Gray Guy? For the past 12 years, they had been systematically collecting scat (poop or droppings) deposited by the wolves. The immigrant wolf was discovered after Vucetich and Peterson collaborated with geneticists Jennifer Adams and Leah Vucetich from Michigan Tech and Phil Hedrick of Arizona State University, to examine the DNA contained within the scat. The geneticists found a scat that carried several alleles -- alternative forms of a gene -- that had not previously been seen in Isle Royale wolves. Through field observations, Peterson and Vucetich confirmed that this scat belonged to The Old Gray Guy. ... Click here to read the rest of this article on the Michigan Tech News.