Introduction: The beginnings -- 1. The spaniels of San Marcos : what is a dog and who cares? -- 2. Cooperation between species -- 3. Homo canis : why humans are different than all other primates -- 4.

Pets feel like a modern comfort, but their origins stretch back tens of thousands of years. Wolves became dogs long before agriculture, while cats likely domesticated themselves around early farms.

It might sometimes feel hard to believe when you're looking at a Chihuahua in a cushy dog bed or a golden retriever in a yellow raincoat and boots, but domestic dogs - yes, all domestic dogs - are the ...