The one about murder

Safiin is puzzled..
watched a documentary when i fnd out that a 'group' of crows is called a murder. a murder of crows.

then i went to search for more pluralities..
an unkindness of ravens
a litter of pigs
a kindle of kittens
a clowder of cats
an effluvium of eels
a building of rooks
a parliament of owls
a tidings of magpies
a shrewness of apes
a string of ponies
a mustering of storks
a knot of toads
a descent of woodpeckers
a crash of rhinos
a murmuration of starlings
a hover of trout
a ostentation of peacocks etc

all these pluralities... whoever came up with these names?? geez...