The Bee's Knees
What is so special about bees' knees? The phrase bee's knees was first recorded in the 18th century, when it was used to mean something very small and insignificant. It's not clear how or why the meaning of this expression evolved to describe an outstanding person or thing. I'm wondering whether it's a coincidence that it sounds very much like 'the business'?
A relatively recent animal-related addition to our language is the expression to jump the shark. It refers to the beginning of a period of inexorable decline in quality or popularity of a television programme that's past its prime, and usually involves the use of a gimmick or unbelievable plot created by the writers in a desperate attempt to retain viewers. The original shark-jumping occurred in an episode of Happy Days, where the lead character, über-cool Fonzie, performed a water-ski jump over a shark. The show's ratings continued to decline after this.
The term kangaroo court arose in disputes over land-ownership claims in the California Gold Rush in the 1850s, and alludes to unofficial court proceedings in which justice proceeds by leaps and bounds, rather than conforming to established legal precedents.
Finally, cloud cuckoo land, that unrealistically ideal state, was penned by the Greek dramatist Aristophanes in his play The Birds, in which a perfect city in the clouds was built by our feathered friends. Now that's what I'd call strictly for the birds.