Many species of bird who hadn't resorted to eating other birds went and lived in the new apple trees and started eating the apples."These tree things are great",said one bird "We should live in them instead of near that freezing cold ocean with no food in it".And so the first nests were built,many birds became wealthy from building nests and selling them for extortionate prices(apples became their currency),the species who started this practice became known as the 'Spotted Real estate Sparrow'.
Proof that L-Space exists in this universe
Fact 1:Heavier things distort time and space more
Fact 2:A page with ink on it is heavier than an unprinted page
Conclusion:A book distorts time and space more than blank papers