As Google has decided to work in circles, we decided to put together a collection of some of the best circles in nature.
Circles make strong defensive positions, leaving no individual exposed. Take this characteristic muskox behaviour – the herd huddles together, encircling vulnerable calves inside a protective wall of adult bulk and sharp horns. These young are certainly no easy target for a hungry wolf, bear or any other predator.
A ‘fairy ring’ is a naturally occurring circle of mushrooms. The visible part of this mushroom is the fruiting bodies, arising from a singular spore in the centre. They are also places where elves gather to dance, apparently!
The humpback whale fluke print – a perfect circle of calm in a choppy ocean. As the humpback dives, it arches its back (hence humpback), raising its tail above the water. This print is all that’s left on the surface. Top marks for this dive.
It’s obvious where this subspecies gains its name – the Ellipsen waterbuck (Kobus ellipsiprymnus ellipsiprymnus) is easily identified by the broad, white ring encircling its rump.
Circles of ages
Perhaps the most famous example of circles in nature – the rings of a tree trunk. New rings of cells are laid down annually, meaning it’s possible to work out how old the tree is. Unfortunately this means telling the age of a tree involves cutting it down.
Birds are great at keeping the nest immaculately clean, and this leads us to our next natural circle: a circle of guano. Marking the edge of this blue-footed booby’s nest, this is one circle I wouldn’t want to join…
Hidden in the coldest and driest continent on earth is a fantastic landscape of ice. About 99% of Antarctica is covered by an ice sheet, reaching over 4 kilometres thick in some places. Making our list of natural circles is this eroded iceberg – stunning!
Lauren Pascoe, ARKive Media Researcher