They all have inherent spiral shapes that conform almost perfectly to the ‘golden spiral’, which is derived from a mathematic formula. A golden spiral is a logarithmic spiral with a growth factor of ‘Phi’, which is the golden ratio – that means it gets wider by a factor of Phi for every quarter turn it makes.
Howlers are New World monkeys found in tropical Central and South America. They are aptly named for their cacophonous cries. When a number of howlers let loose their lungs in concert, often at dawn or dusk, the din can be heard up to three miles (five kilometers) away. Male monkeys have large throats and specialized, shell-like vocal chambers that help to turn up the volume on their distinctive call. The noise sends a clear message to other monkeys: This territory is already occupied by a troop.