 Well, I'm going to talk here about obsidian and how it represents the spread of agriculture into the western Mediterranean, unlike what we've seen in Anatolia and elsewhere, where things are not all at the same time, what we see when you get to Italy and further west, a real neolithic package, the domesticated animals, the domesticated plants, and the beginning of obsidian transport and trade all at the same time. I'm going to talk just a little bit about the methods of analysis that we use today, also specifically about obsidian subsources so that we can be very specific about where the obsidian is coming from, how it is acquired, and how that represents different kinds of socioeconomic organization. And in the central Mediterranean, we already know, based on the plant and animal finds and so on, ceramics, what's called the Cardial Impressed Ware, the Cardial Pottery culture, which spreads mostly in the coastal area of southern France, Croatia, the Boote and all of Italy, and a little bit into Spain, and a kind of drawing line between that area and the part further east into Greece and Albania and so on. Obsidian has been found literally in more than a thousand different archaeological sites. We have several different sources all on islands, here in the central Mediterranean, tiny islands of Palmarola, Pantilleria, and Lipiri, and then the large island of Sardinia. And so, obviously, in a whole lot of places here, there's the potential for the obsidian coming from different sources that are quite a good distance away. I always have to thank Colin Renfrew and colleagues for their early studies, which generally came up with a kind of geographic thing that you would have estimated to begin with, where Sardinian obsidian is more here in the western part of the central Mediterranean, whereas the Lipiri obsidian is largely in the eastern part, Palmarola obsidian, we know the quantity and quality and some other characteristics suggested that it would not be as widely distributed as the other sources. I'm not going to get into the different kinds of analytical methods that are used today. Obsidian sourcing is fairly straightforward. We can use 10 different kinds of instruments to do this, but being able to do non-destructive analysis with the portable XRF machines allows me to go and visit many different museums, do the analyses on the spot very quickly and non-destructively so everybody is happy as far as that goes. And again, we can clearly distinguish the different sources there, Lipiri, Palmarola, different Sardinian groups, Pantilleria, Melos over in the Aegean, Carpathian sources and so on. Again, this is something that at this point is very straightforward. It is important to not just say that the obsidian came from Sardinia or Lipiri or elsewhere because there are different subsources and this says something when we can identify those specific locations, we can address things, for example, like territorial control, which is something that we probably don't see in the early Neolithic by the later Neolithic. I argue that that is definitely in place, that you have specialists producing obsidian in very specific locations and being able to identify that specific subsource for the artifacts that are distributed allows us to assess that kind of thing. And I've done myself a geological survey on these different islands and so we can identify, for example, Canedo Dentro in this small little outcrop here, whereas in the Gabalato area there are different outcrop areas. Unfortunately, Lipiri was largely covered over by historic volcanic events so that the, both the archaeological sites and some of the source locations here just simply cannot be studied as well as we would like. But in any case, as you can see here, I can go and distinguish between the Canedo Dentro, two different Gabalato gorge groups, and then another source that simply does not produce very large pieces of obsidian so we can kind of exclude that one to begin with. Going to Sardinia, again, there are different outcrops and so on that can be distinguished chemically and different qualities, different other characteristics which are important when we consider how people were going, when you have multiple choices, are they making selections for certain kinds of reasons, color, the size of the world blocks, the accessibility of the material, and so on. And again, we can easily distinguish these different subsources on Sardinia. So at this point in time, about 16,000 obsidian artifacts have been tested here in the Central Mediterranean, ranging from the Neolithic through the Bronze Age time periods. And so this gives us a lot of data where we can potentially go and look at changes over time and how that represents the sociocultural, political, economic aspects of the different societies. And you all know what obsidian looks like and technology is another thing that changes over time and we have to integrate that with the use of materials from different sources as well and the evolution of production, whether this is something that is more on a casual basis or whether you have specialists doing these kinds of things. So with my colleagues, we have analyzed obviously quite a large number of pieces and are doing the techno typology as well as the sourcing. Okay, at this point, coming from the source island of Liperi over here, pieces of obsidian from that source are found throughout Italy, into Southern France, into Tunisia, and so on. And this is starting right away in the early Neolithic and that just has something about the rapidity of the spread of agriculture in these coastal kinds of areas around the Mediterranean that happens so fast. One of the things that I argue for is that this is a northern, northern northwestern spread of the obsidian from Liperi going this way. There's a reason that I'm not showing any place over to the east of here because at this point only one single piece of Liperi obsidian has been found to the east of this line. So the spread of the obsidian is very much in the same direction as the spread of agriculture. And why is that? They clearly were able to go out in whatever kinds of boats or vessels going from these source islands and in fairly significant open water travel to the beginning of the early Neolithic. So why are they not going in the opposite direction? Here in Sicily, among the analyses that are done here, there's different percentages of the two major sources, Pantilleria, which is to the southwest, and Liperi over here. Again, there are differences in the quality and quantity of these kinds of materials. And it's no surprise that the Pantilleria obsidian is found much more in the western half of Sicily. But one of the very interesting cases I want to show is the island Malta, or the country of Malta and the two separate islands of Gozo and Malta, which is also really in the open water area and tells us something about the capability they had for maritime transport. And that is that at the site of Scorba, which is more of a residential as well as ritual site, most of the obsidian being found there is coming from Liperi. Whereas at the site of Shara on Gozo, most of the obsidian is coming from Pantilleria instead. So there is definitely some kind of selection of these materials. And that one, of course, is not in the direction of agricultural spread, but the only way you're going to go from Malta is from Sicily to begin with. At the site of Ustica, this is a tiny island five square kilometers. There's actually six different archaeological sites, one of which at least dates back to the very beginning of the early Neolithic. And most of the obsidian found there is coming from Liperi. Whereas at the sites over here in the northwestern part of Sicily, where you would think boats would be going to get up to Ustica, have a different percentage of the Pantilleria versus the Liperi obsidian. And so this supports my hypothesis that there was more direct travel between these islands than going to the nearest coastal areas, then across the coast, and then back up to another island. And by analyzing literally hundreds and hundreds of artifacts, we can do these kinds of percentages and predict these distributions. I already said something about the difference between the Proctor of Circle and Scorba on Malta, so move along. And I also said something about that site of Ustica here. Now at the same time that I argue that they were doing pretty well in open water travel 8,000 years ago, people bring up questions. What about going all the way from Ustica or from Sicily over to Sardinia? We had no evidence whatsoever of that. Well, what kind of evidence would we have would be pottery and obsidian, the main materials found in the archaeological record. And this strongly suggests that when possible, people follow coastal routes, more or less be able to see your destinations and so on. And at the same time, we actually have found now some obsidian objects, one piece, one piece only in Sicily and small numbers in the southern part of Italy. But I will show you shortly a map showing that that's really the end of the down the line trade making it that far south from Sardinia. So there were limits in the maritime transport that they had at that time. The different sub-sources are very important in Sardinia because we have shown that the use of those sources changes over time. The very first study that I did 25 years ago showed that they were mostly using a variety in the earlier Neolithic and then it became dominant using the Sardinian sea subsource by the late Neolithic. And after analyzing this for many other sites in Sardinia and Corsica, again in the early Neolithic, we find the use of those major groups A, B and C. But then in the late Neolithic, they're not using the B as much and it becomes dominated at most of these places by the Sardinian sea. And what we have gone and done is an actual excavation near the Sardinian sea subsource area and discovered actual major workshops where they were collecting raw material and producing literally right on the spot, more than two meters down. Here's a pile of the debitage for major production that clearly was far more than would ever be used by the people living nearby. This is something that you had specialists producing here and trading and sending this off to places much further away, including into Corsica to the north and have looked at different varieties and things there as well. Here I'm showing in these large red dots, these are finds now of Sardinian obsidian in the southern half of Italy in the one piece in Sicily. But we could take all of these pieces and put them in the palms of my hand here compared to the great quantities, the high percentage of the overall lithic assemblage that is coming from Sardinian obsidian, not just on that island, but in Corsica and getting on to the mainland here as well. Leapery obsidian though travels even further than the Sardinian obsidian. Here we are in the central part of the Adriatic and we find obsidian at many of the archaeological sites here, insignificant quantities still, but it's also traveling across the Adriatic which is probably the opposite difference of the spread of agriculture. A total separate area of my research is looking at the early arrival of domesticates right here in this part of central southern Italy, not one of the previous hypotheses that people traveled mostly over land up to the top of the Adriatic and then back down the peninsula. And this is based of course on radiocarbon dates and so on. And it does help that there are some islands in between, some of which were also occupied going back into the early Neolithic period. And one of the things also to mention is on one of these islands we actually do find some pieces of Milos obsidian coming all the way from the Aegean but this has nothing to do with the spread of agriculture because these show up later in time at the very end of the Neolithic. Heading a little bit north here into central Italy at the site of Poggio Lovastro looking at the different percentages. We have clear competition if you will between leapery, palmarola and the different Sardinian subgroups here but also consider this is an inland site. So you have the travel obviously from one of the islands then to the coast from where the sources are on Sardinia to the coast of Sardinia then over water to get here and then further inland. So there's lots of people, different groups that are probably involved in the long distance spread of obsidian during these time periods. This is a place on one of those islands in between closer to Sardinia no surprise that Sardinian obsidian is most of what's there but there's still pieces coming from leapery and palmarola in the early Neolithic period. So these are not organized economic civilizations yet going on they didn't have some exclusions or that kind of thing people on boats traveling largely independently at that time. Heading even further north to the site of Pescale another early Neolithic site which is dominated by Sardinian obsidian and some from leapery as well. But go and compare this then with these sites not too far north and equally inland you can tell from the difference in the colors here that at all four of those sites they're dominated by the leapery obsidian and the Sardinian is only 4% of the total. So how can we go and explain the selection of these totally different materials and where they're coming from. And something even further different is at these sites over in southern France not only are they dominated by Sardinian obsidian but specifically the Sardinian A subgroup whereas what we saw back in Sardinia and Corsica is it's mostly the Sardinian C group. So there's definitely things going on here not just in the ability to travel over great distances to have obsidian to use because it's sharper than other stone tools and so on and it looks different and so forth but this really involves all of these different variables into coming into some kind of conclusion. And of course we can't just simply draw lines between the geological source and well we've identified by chemical analysis where it's coming from because we know that's not the travel directions that we're going on in the Neolithic period. We have to consider again these variables I like to put them in my version of the chenoperatoire from the archaeological site where the objects have been deposited identifying the source where it was originally acquired and then who is it that is going and reducing the raw material transporting it over both land-based and water-based distances what is the obsidian used for after you chip the edge is it modified and reused these are all things to consider in interpreting what was going on in ancient times and just to bring up reasons why obsidian may have been important is it's very sharp, much sharper and so it's very useful for things like cutting skin, cutting hair various things like this and we do have to say that the vast majority of obsidian finds do not have obvious wear patterns they're not being used on very hard materials and they seem to be used very casually that is short term so again these are variables that we need to consider overall in studying obsidian. Thank you.