Dentition mammals the infants have a set of teeth that fall out and are replaced by adult teeth. These are called deciduous teeth, primary teeth, baby teeth or milk teeth. Animals that have two sets of teeth, one followed by the other, are said to be diphyodont. Normally the dental formula for milk teeth is the same as for adult teeth except that the molars are missing. Because mammal teeth are specialised for different functions, many mammal groups have lost teeth not needed in their adaptation. Tooth form has also undergone evolutionary modification as a result of natural selection for specialised
I Should Have Known Better film, and it appears on the soundtrack. Capitol Records released "Something New" a month later with songs from the UK version of "A Hard Day's Night" that were not used in the film. The songs were also later released by Capitol on the "Hey Jude" compilation album in 1970. "I Should Have Known Better" was released as a single in a number of continental European countries, including Norway, where it reached number 1, and West Germany, where it reached number 6. In Sweden, the song topped the Kvällstoppen Chart for four weeks. The song is performed in the train compartment