Val Geist is world renown as the dean of behavioral ecologists (ethologists) of the hooved mammals (ungulates) of the northern hemisphere. Fritz Walther, an extraordinary ungulate ethologist in his own right, once described Geist as having a mind that combines the vastness of the Russian Steppe (Geist's natal homeland), with the meticulousness of Germany (where he spent his youth) and the audacity of North America (where he has spent his adulthood). Bull's eye.
I know of no wildlife biologist with greater depth of knowledge and creative insight, or greater courage and dedication in applying his knowledge to the challenge of real world conservation.