As humanity has got richer, animal's roles have changed. People need their services less than before. Fewer wolves and thieves meant less demand for dogs for protection; the internal combustion engine (内燃机)made horses unneeded; modern sanitation (卫生设备)kept rats in check and made cats less useful. No longer necessities, domestic animals became luxuries. Pet-keeping seems to kick in when household incomes rise above roughly $5,000. It is booming.
The trend is not a new one. Archaeologists (考古学家)have found 10,000-year-old graves in which dogs and people are buried together. Some cultures -- such as in Scandinavia, where dogs have long been both working dogs and companions -- have kept pets for thousands of years. But these days the pet-keeping urge has spread even to parts of the world which have no tradition of sinking into a comfortable chair with a furry creature.
The pet business is growing even faster than pet numbers, because people are spending more and more money on them. No longer are they food - waste - recyclers, fed with the remains that fall from their masters' tables. Pet - food shelves are full of delicacies crafted to satisfy a range of appetites, including ice cream for dogs and foods for pets that are old, diabetic or suffer from sensitive digestion; a number of internet services offer food, tailored to the pet's individual tastes.
In the business this is called "pet humanisation" -- the tendency of pet owners to treat their pets as part of the family. This is evident in the names given to dogs, which have evolved from Fido, Rex and Spot to -- in America -- Bella, Lucy and Max. It is evident in the growing market for pet clothing, pet grooming and pet hotels.
People still assume that pets must be working for humanity in some way, perhaps making people healthier or less anxious. But the evidence for that is weak. Rather, new research suggests that dogs have evolved those irresistible "puppy - dog eyes" precisely to affect human emotions. It has worked. The species that once enslaved others now works very hard to pay for the care of its pets. Sentimental (多愁善感的)Americans often refer to themselves not as cat-owners but as the cat's "mommy" or "daddy". South Koreans go one further, describing themselves as cat "butlers". Watch an unlucky dog-walker trailing "his" hound (猎犬), plastic bag in hand to pick up its mess, and you have to wonder: who's in charge now?
