Fourteen colorful spreads display the impact on human and animal life of microwaves; ultra-violet and infra-red light; electromagnetic waves; ultrasound and infrasound and scents and smells beyond human detection. Understanding these hidden forces enables us to use them in many ways. But many animals also use them. They help cats to catch mice, elephants to find mates, vampire bats to find victims. Ants 'talk' by exchanging smells. Indeed, without 'Invisible Nature', life on Earth would not exist at all.