activation analysis (INAA) to compare over 1,000 Mesoamerican Olmec-style ceramic artifacts with 275 samples of clay so as to "fingerprint" the origin of that pottery. They found that "the Olmec packaged and exported their beliefs throughout the region in the form of specialized ceramic designs and forms, which quickly became hallmarks of elite status in various regions of ancient Mexico". In August 2005 the results of another study were published. This study used petrography to analyze 20 pottery shards, and found that five of the samples from San Lorenzo were "unambiguously" from Oaxaca. Based on this evidence, the authors concluded that the "exchanges of vessels between highland and lowland chiefly centers were reciprocal, or two way" which "contradicts recent claims that the Gulf Coast was the sole source of pottery" in Mesoamerica. The results of the INAA study were later defended in March 2006 in two articles in Latin American Antiquity, in particular contrasting the sample size of the INAA study (roughly 1000) with the sample size of the petrography analysis (20). An emerging middle ground In the early 21st century it seems that a middle ground between the mother and sister culture positions may be emerging. Pool (2007) thus concludes that while San Lorenzo emerged early as the largest the most developed polity of Mesoamerica and the earliest evidence of several of the defining traits of Mesoamerican culture is found there, the Olmecs emerge looking less like a mother culture than as a promiscuous father culture spawning offspring generously with many different mothercultures all over mesoamerica. This formulation emphasises the viewpoint that influence from the Olmec heartland merged with many local traditions creating local expressions with both Olmec and non-Olmec roots. it follows from this approach that the type and degree of Olmec influence varies greatly from location to location within Mesoamerica. Flow of influence If Olmec influences flowed out of the heartland in what is generally seen as a less than bilateral transfer, then how did this happen? How were the hallmarks of Olmec culture transmitted to sites hundreds of kilometers/miles distant from the heartland? Many theories have been advanced including: Olmec military domination, Olmec colonization of other regions, Olmec artisans travelling to other centers, Missionary activity, Conscious imitation of Olmec artistical styles by developing towns, Long-range trade by Olmec merchants. There is little or no evidence to support Olmec military domination. Very little Olmec or other Early