【英语时差8,16】小狗怎么吃东西?(在线收听

How Dogs Eat If you’ve ever watched a dog eat you’ve probably marveled at how quickly it gulps down its food. You might even wonder why, no matter how hungry a dog is, it will often eat as much food as you put in front of it. Dog owners may be concerned about this behavior, but it poses no problems for the dog. People chew their food and try to teach their children to eat slowly because digestion for humans begins in the mouth. Our saliva mixes with food and prepares that food to be broken down into its primary nutrients once it enters the stomach. A dog’s digestion, on the other hand, doesn’t begin until the food reaches the stomach so they do not need to take time chewing their dinners. Most dogs probably eat so quickly because in the days before they were domesticated, they had to survive by eating their prey before another dog or scavenger animal stole it. The evolutionary programming of dogs dictates that they eat and keep moving. As a species in the wild, they didn’t have the luxury of hanging around and eating at their leisure. Even their teeth aren’t designed for them to savor their food. While most of the teeth in a human’s mouth are flat and designed to facilitate chewing, most of the teeth in a dog’s mouth are pointed, and designed to allow a dog to grab its food and swallow it whole. Hundreds of years of domestication hasn’t changed most dogs’ eating habits very much. Even if a dog has been given regular, dependable meals every day, it will still gulp those meals down in a flash, ensuring that no scavenger will take its food away.

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