the work introduces the genus Zapus, noting the distribution of jumping mice across northern North America, from the Arctic Circle to regions as far south as central California. The author emphasizes the general lack of comprehensive taxonomic attention for these rodents since a prior revision in the late 19th century, despite the identification of new subspecies. Additionally, the section outlines the research methods and acknowledgment of collaboration with various institutions, underscoring the extensive study based on thousands of specimens collected from multiple geographic locations. This establishes a strong foundation for the detailed analysis that follows, delving into the paleontological aspects, species characteristics, and systematic accounts of the identified species. (This is an automatically generated summary.)