1. Calling for attention could mean asking for a mate, or simply marking territory. 2. The rattlesnake's rattle serves as a warning to all its prey and predators. 3. A sweet scent for a plant attracts insects to pollinate their flowers. 4. Some may have a unique way of calling out, or weird movements. Take tropical birds for example. 5. I think it's because that the females are attracted to a certain call or movement. 6. communication is talking to each other. 7. Stimuli can induce the hypothalamus in an organism's brain to react accordingly. 8. Animals need a voice, or a call, or a maovement, or anything to get their point across.
