Jack London 
The Call of the Wild [EPUB ebook] 

The Call of the Wild  by Jack London was first published in 1903. It’s an adventure novel that takes place during the Klondike Gold Rush in the 1890’s when around 100, 000 people moved to Yukon in Canada in search of gold. During this time, sled dogs were in high demand, and the main character of this book is in fact a St. Bernard–Scotch Collie mix dog called Buck. Stolen from his home at a ranch and sold as a sled dog, Buck must learn to become more primitive and figure out how to fight for survival among his new, harsh conditions. His new owners are cruel and mistreat Buck, but eventually he finds a new, kinder owner in John Thornton. His journey to become a completely feral dog is complete when Thornton dies and Buck fights to become part of a pack of wolves.
London had spent some time in Yukon, living in a frontier town for almost a year. Exploring themes such as nature versus nurture,  
The Call of the Wild  is written in a way that was ‘a protest against the ‘humanizing’ of animals’, as London accused other writers of doing.