It is a common misunderstanding that seeds are a sufficient diet for companion birds. After all, wild bird feeders are filled with seeds, right? However, while wild birds enjoy the seeds people provide, they also eat a wide variety of other foods, including plants, insects, nectar, and, for some species, other small animals. In the wild, the same is true for cockatiels, parakeets, macaws, and other parrots. In their natural setting, these birds consume an almost unbelievable variety of foods.

Obesity (the storage of excess fat) is usually caused by excessive food intake and insufficient exercise. According to estimates, 40% to 50% of dogs are overweight and 25% of dogs are obese. Obesity is more common in older, less active pets. Dogs that are fed homemade meals, table scraps, and snacks are more likely to be overweight than dogs that are fed only a commercial pet food.

Whether animals feel emotions in the same way people do is a mystery. However, their behaviors are commonly interpreted as reliable expressions of mood—for example, relaxed, fearful, or aggressive. Based on observed changes in behavior, it is thought that some dogs and cats grieve after losing a close human or animal companion. In 1996, the ASPCA conducted a study of mourning in companion animals and found that more than half of dogs and cats had at least four behavioral changes after losing an animal companion. Many of these changes, such as eating less and changes in sleep patterns, were similar to behaviors exhibited by grieving people.