I was fortunate in getting a grant from the Alfred P. Sloan Foundation to work on the prehistory of languages, and so we had a number of interesting conferences where we got leading linguists and archaeologists and others who were interested to discuss some of the problems in the prehistory of languages. Because early language is a peculiar subject, obviously you don't have evidence of language until you have writing, which is at the earliest around 3,000 BC, much later obviously in many parts of the world, but it's clear if you have different languages of the same family spread across Europe and you already have written indications of them around 1300 BC in Greece and around the same date in Turkey, that Proto-Indo-European must be much earlier so if you begin to reconstruct the ancestors of language families, to recreate the Proto-Indo-European language or Proto-Semitic language or Proto-Afro-Asiatic language, that's taking you quite deep into prehistory even if you're not quite sure how deep. And this was of interest to me because of that problem that Christopher Hawkes had raised. He was saying you can't have that theory of yours about the evolution of religion because you're forgetting about the Indo-Europeans and I didn't really think the Indo-Europeans were very relevant because as far as I was concerned, they had appeared on the scene much earlier and whether they were Indo-European or not didn't really affect the problem, whereas if you believed that the Indo-European languages had come much more recently, then you had to write the archaeology differently. You had to find the migration that brought in the Indo-Europeans that were responsible for these changes, so it, and it was a way, it was again somewhat this old endogenous, exogenous story, were the developments in Europe essentially European developments, although with an Indo-European component very early, or were they the product of more recent migrations or diffusionist processes or whatever? So it related to that earlier problem, but it meant that the language question was a real constraint because archaeologists were being told the way they should construct their narrative or their theories, you had to bring in the Indo-Europeans at the beginning of the Bronze Age and very much the same applied to the so-called Celts and there were very clear theories, which indeed Professor Hawkes had been associated with about the coming of the Celts to Britain in the Iron Age and the Celts were supposed to be people who spoke Celtic languages, which was a subgroup of Indo-European and supposed to have characteristic material culture with a La Tène type decoration and so there was a very clear cut theory that the Celts came to Britain in the 1st century BC so the whole of Iron Age archaeology was being written in terms of the coming of these people in the 1st century BC who were bringing their Celtic speech and these other things with them. Well, this was already being questioned. Roy Hodson was one of the Iron Age specialists in Britain who was questioning these supposed successive migrations of the, of the Celts, but I very much followed his views and to me it was probable that the Celtic languages, which is a subgroup of Indo-European, developed in place really, in France and Ireland and in Britain after the first farmers speaking their Proto-Indo-European language had come so you didn't need any further invasions. You had the coming of Proto-Indo-European with the Neolithic, but after that you got elaboration and linguistic diversity divergence so that you've got the Celtic languages emerging in place so you didn't really need any invasions for the British Iron Age and that was an important point, to somehow get oneself free of the constraint of having to think when do we bring in these Celtic languages or Greek languages or Slavonic languages or whatever it might be, and so it did seem to matter archaeologically. And so we had one very interesting meeting, time-depth in historical linguistics, and it really became clear that there weren't any very good arguments to prevent your setting Proto-Indo-European much earlier than had originally been supposed and the arguments that there were, were often rather circular ones. You couldn't have Indo-European that early because it would be earlier than Proto-Afro-Asiatic so you say, well, how do you date Proto-Afro-Asiatic? Oh, well, it's around the same time as Proto-Indo-European and so you went round in these complete circles. So the conferences were very interesting and most of the linguists stuck to their guns, it has to be said, I think it has to be said that in linguistic studies, historical linguistic studies, the majority of linguists don't really think in these terms, but a lot more work has gone on. I could see that the same arguments would apply to the Bantu languages and that their farming language dispersal model, the notion that as farming spread, so did the language of the first farmers in different regions of the world. That could apply. And Peter Bellwood in Australia, working on the Pacific languages and the peopling of the Pacific, had come to very similar ideas for the Pacific and so together we've been developing these ideas. Interestingly enough, they don't always find favour with the Neolithic specialists in Britain because they, following Eric Higgs's thought had been suggesting that maybe the transition to the Neolithic way of life in Britain, hadn't really been due to much in the way of influences, certainly not people from South-East Europe, but was the result of local processes in the, arising from the Neolithic transition from the Mesolithic and I was quite attracted to that line of thinking but as far as I was concerned, it was clear that the wheat and the barley and the sheep and the goat really did originate in the near East and that is agreed and not significantly disputed, so those were something that made possible the Neolithic way of life in Britain. And so the question devolves on to what extent was there a great movement of people and that's then where you very soon begin to get interested in the molecular genetics.