Mark Shuttleworth the founder of Ubuntu codenamed the next Ubuntu 13.04 as “Raring Ringtail”
He Explained the reason of this name:
we want to have the phone, tablet and TV all lined up. So I think it’s time to look at the core of Ubuntu and review it through a mobile lens: let’s measure our core platform by mobile metrics, things like battery life, number of running processes, memory footprint, and polish the rough edges that we find when we do that.
The tighter we can get the core, the better we will do on laptops and the cloud, too.
What is Ringtail? According to Wikipedia:
The ringtail (Bassariscus astutus) is a mammal of the raccoon family (thus not actually a cat), native to arid regions of North America. It is also known as the ringtail cat, ring-tailed cat or miner’s cat, and is also sometimes mistakenly called a “civet cat” (after similar, though unrelated, cat-like omnivores of Asia and Africa). The ringtail is sometimes called a cacomistle, though this term seems to be more often used to refer to Bassariscus sumichrasti.