Thanks a lot TheSnail you saved me a lot of digging about.

People outside science and for that matter outside of most academic study use the word and so the concept "theory" to mean any idea that may or may not have some kind of possibility of turning out to be right:

"Their is a theory that many Indo-European languages have so much in common that they have a common root in a language spoken thousands of years ago. "Most languages in Europe, the Middle-East, and India appear to descend from a common ancestral language known to scholars as "proto-Indo-European," as set forth by William Jones and his work with Sanskrit."

When Jones spotted the likenesses he was suggesting what scholars now call a hypothesis. After a period in which much study was carried out and much evidence collected it can rightly be called a theory. So a theory is a collection of evidence and ideas that hang together well, help to explain things and make predictions possible.

The peopling of the planet is a fascinating story which is being revealed by detailed academic study of genes, archaeology and language.

Sorry for be patronising EBarnacle but academic study leads to a deeper understanding. Suggestions built on almost no evidence at all are just a waste of time and a distraction.