Meanwhile, starting in the late 1970's, scientists began to find wide evidence that many animals relied on the Earth's magnetic field for navigation.
When a young animal relies on its parents for survival, they need a constant stream of information to decide how to care for it.
Many animals rely on plants for shelter as well as oxygen and food.
But the animals that form colonies around the black smokers don't rely on the sun at all.
They reveal, the researchers say, the importance of friendship in complex societies, where animals live together and rely on one another.
The animal relies on the orientation of its head for aim.
Being cold blooded, these animals rely on heat from an external source such as the sun to regulate their body temperature.
But not all animals, even on their home ground, can rely on such a well-learned map.
Most animals relied on scent anyway, and there was nothing he could do about his scent.
Plants and animals rely on different forest ecosystem stages to meet their habitat needs.