Holk's research explores autonomous systems, particularly the use of internal world models to plan and control movements thus forming the basis for cognition. Holk is most renowned for his bio-inspired, decentralized models of walking control. His research on stick insect walking and its implementation in robotics earned him the prestigious Körber European Science Prize in 1993 (together with Felix Chernousko, François Clarac and Friedrich Pfeiffer).
Holk studied Biology, Physics and Mathematics at the University of Freiburg. He received his PhD in 1972 from the University of Stuttgart (group of Ulrich Bässler) for his work on pattern recognition in honeybees. Holk was research fellow at the Max-Planck-Insitute for Biological Cybernetics in Tübingen (group of Kuno Kirschfeld) and the University of Kaiserslautern. During that time, he obtained his habilitation in Zoology. In 1981, Holk was appointed group leader at Bielefeld University and founded the Department of Biological Cybernetics, which he led until 2009. From 1989 to 1997 Holk was member of the directorial board of the Center for Interdisciplinary Research (ZiF) at Bielefeld University. He was fellow at the Institute for Advanced Study Berlin (Wissenschaftskolleg zu Berlin) in 1995 and 2008. Since 2009, Holk is a principal investigator at CITEC.