Many of the world's folk and children songs are built around the pentatonic scale. Any pitches of a pentatonic scale may be played in any order or combination without clashing. Songs built around pentatonics therefore feel quite natural to sing - they also may all be sung in canon (or rounds). Here's a fascinating demonstration of the universal 'sense' of the pentatonic scale from the World Science Festival a couple of years ago:
http://www.youtube.com/watch?v=ne6tB2KiZuk
To find out more about what inspired The Singing Tree, visit:
We're very excited that in November 2015, musician, broadcaster and author Cerys Matthews MBE became Patron of the Singing Tree.