As Japan's birth rate plummets, its pet population is exploding. With fewer children to dote on, many Japanese couples and single adults are lavishing attention on their animals, pampering them with everything from spa treatments to Chanel attire, and sparking a boom for the pet industry. Why has Japan suddenly become a "pet superpower"? Here, a brief guide:

Why do so many Japanese obsess over pets?
The country's birth rate has slumped to a perilously low 1.39 children per woman (America's birth rate was 1.93 children per woman as of 2010). If the trend holds, the government estimates that the country's population will collapse from 128 million to 43 million over the next century. But the falling birthrate, which has been blamed on everything from shifting attitudes toward sex to economic problems, hasn't eliminated the basic human need for love and companionship, and an increasing number of childless couples and single adults are filling the void with their pets.

Just how pet crazy is Japan?
The country has 22 million pets compared to just 17 million children under age 15. Tiny lapdogs such as miniature dachshunds, poodles, and Chihuahuas are especially popular with the country's aging population, particularly in dense cities like Tokyo, where most people live in small apartments. An increasing number of people in Japan say that they see their dogs and cats as family members, and they're spending accordingly. The country's pet industry is estimated to be worth $18 billion per year.

What are pet owners spending on?
Pet food, of course, which accounts for 40 percent of the industry. But pet owners are also laying out a lot on pampering. They buy premium doggie garments from labels such as Chanel, Dior, Hermès, and Gucci — a poodle pullover can cost $250, according to Britain's Guardian. They frequent restaurants which allow pets to sit at the table with their owners and lap up organic meals. They indulge in doggie yoga classes and hot-spring resorts where lapdogs can get one-on-one swimming lessons, bubble baths, and pressure-point massages.

Anything else?
Absolutely. For some pets, the pampering doesn't end with death. Some temples lay deceased dogs to rest with full Buddhist rites, at $8,000 a pop for a deluxe funeral and cremation. "These days, people grieve more for their pets than for parents or grandparents," a monk at a 1,000-year-old temple in a Tokyo suburb tells The Guardian. "It is because pets are just like their child, so it is like losing a child."

Sources: Daily Mail, Guardian, Japan Daily Press, Jezebel