Causes and symptoms. Fatigue may be the result of one or more environmental causes such as inadequate rest, improper diet, work and home stressors, or poor physical conditioning, or one symptom of a chronic medical condition or disease process in the body.
1 A hummingbird will use its tongue to lap up nectar from flowers and feeders. 2  A hummingbird's tongue is grooved like the shape of a W. 3  Hummingbirds have tiny hairs on the tip of the tongue to help lap up nectar.
Hummers have a fast breathing rate, a fast heartbeat, and a high body temperature. They must feed every 10 minutes or so all day, and they may consume 2/3 of their body weight in a single day.A major part of a hummingbird's diet is sugar. They get it from flower nectar and tree sap.