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The animals on the cover of Essential CVS are bobacs (Marmota bobak). Also known as "steppe marmots" because of their wide distribution in the steppes (vast, grass-covered plains) of southern Russia and Kazakhstan, bobacs range as far west as central Europe. Though they are slightly larger than black-tailed prairie dogs, bobacs are otherwise quite similar to their North American counterparts.

Unlike most marmots, which live primarily in mountain environments, bobacs prefer to build their sprawling burrows in open, rolling grasslands or on the edges of cultivated fields. Bobacs are strictly diurnal and are most active during the cooler hours of the day. When they are outside of their burrows, it is common for a sentry to stand erect and alert on its hind legs, ready to bark an alert at the first sign of a predator or other danger. After running to their burrows, bobacs will then await an "all clear" call before returning to the surface. During the summer, bobacs eat enough lush vegetation to double their weight. The added fat reserve nourishes them throughout their winter hibernation.

Like other marmots, bobacs are very social animals that live in large groups, or "towns," which may range from a single acre to over 1,000 acres. Towns are subdivided further into "wards" and even smaller "coteries," which are usually made up of a single adult male, one to four adult females, and any number of offspring under two years old. Young bobacs, born in litters of about five or six, leave their natal coterie after their second hibernation. Because their coats can be used as imitation marten fur in hats, coats, and other apparel, bobacs are greatly threatened by fur hunting.

Brian Sawyer was the production editor and copyeditor for Essential CVS . Jane Ellin was the proofreader. Derek Di Matteo, Claire Cloutier, and Colleen Gorman provided quality control. Jamie Peppard provided production support. John Bickelhaupt wrote the index.

Ellie Volckhausen designed the cover of this book, based on a series design by Edie Freedman. The cover image is a 19th-century engraving from the Dover Pictorial Archive. Emma Colby produced the cover layout with QuarkXPress 4.1 using Adobe's ITC Garamond font.

Bret Kerr and David Futato designed the interior layout, based on a series design by David Futato. This book was converted by Joe Wizda to FrameMaker 5.5.6 with a format conversion tool created by Erik Ray, Jason McIntosh, Neil Walls, and Mike Sierra that uses Perl and XML technologies. The text font is Linotype Birka; the heading font is Adobe Myriad Condensed; and the code font is LucasFont's TheSans Mono Condensed. The illustrations that appear in the book were produced by Robert Romano and Jessamyn Read using Macromedia FreeHand 9 and Adobe Photoshop 6. The tip and warning icons were drawn by Christopher Bing. This colophon was written by Brian Sawyer.

The online edition of this book was created by the Safari production group (John Chodacki, Becki Maisch, and Madeleine Newell) using a set of Frame-to-XML conversion and cleanup tools written and maintained by Erik Ray, Benn Salter, John Chodacki, and Jeff Liggett.