Studies on Amerindian dogs, 2: Variation in early peruvian dogs

Remains of dogs have been discovered in Peru for over a hundred years, but relatively little information is available on them. Dating evidence, especially by the radiocarbon method, suggests that the skulls of dogs considered in detail here range from 1030 BC to 1324 AD, with the majority belonging to the past two millennia. Craniometric information is presented on a series of early Peruvian specimens now preserved in Lima and London, representing the majority of material as yet unpublished, and the largest sample so far studied. Additional Peruvian data were also collected from the literature, as well as comparable information on some other Amerindian dog series. It has been possible to indicate that two distinct forms are represented in the Peruvian material.     

The evolution of soil management practices in early Jamaican sugar planting

The wealth of Jamaica in the late 1700s was based upon a sugar planting system. Although contemporaries carefully and fully described this system, they neglected to comment upon its evolution. This paper discusses the evolution of the system's soil management practices during its formative period and compares these techniques to those of related agricultural systems of other places. The interpretation of this information assumes that the evolution of agricultural practices on early Jamaica was consistent with models developed within general evolutionary theory. Several key practices, which originated in Britain, were selectively transferred to Jamaica both directly and indirectly through Barbados, the first British sugar colony in the Caribbean. Those practices which survived in Jamaican agriculture were often modified to adapt them to the island's distinctive physical, social and economic environment.     

Location Modeling Utilizing Maximum Service Distance Criteria

The location set-covering problem (LSCP) and the maximal covering location problem (MCLP) have been the subject of considerable interest. As originally defined, both problems allowed facility placement only at nodes. This paper deals with both problems for the case when facility placement is allowed anywhere on the network. Two theorems are presented that show that when facility placement is unrestricted, for either the LSCP or MCLP at least one optimal solution exists that is composed entirely of points belonging to a finite set of points called the network intersect point set (NIPS). Optimal solution approaches to the unrestricted site LSCP and MCLP problems that utilize the NIPS and previously developed solution methodologies are presented. Example solutions show that considerable improvement in the amount of coverage or the number of facilities needed to insure total coverage can be achieved by allowing facility placement along arcs of the network. In addition, extensions to the arc-covering model and the ambulance-hospital model of ReVelle, Toregas, and Falkson are developed and solved.     

Radiocarbon dating: Some practical considerations for the archaeologist

The article is divided into four main sections in each of which a key aspect of radio-carbon dating is discussed with emphasis on the practical implications for users of dates. The four topics which the article attempts to deal with are, in turn, (i) the effect on the radiocarbon timescale of the variations in atmospheric ¹⁴C now known to have occurred in the past and the role of other absorlute dating methods in investigating these, (ii) laboratory measurement of ¹⁴C, (iii) selection of optimum samples for dating and (iv) some of the limitations of the final dates. The theme is essentially that the technical difficulties of radiocarbon measurement in the laboratory have been overcome to the extent that the physical measurements can now be made with high precision, that is to within ±1% or better, as a routine. Thus, it is more important than ever (a) that only reliable samples having very firm associations should be dated and (b) that pretreatment of such samples by the dating laboratory to remove any age contaminants should be completely effective. However, in addition to the recognized statistical limitations, the absolute accuracy of radio-carbon dating is limited by the past ¹⁴C variations. Coupled with the requirements of proper association and pretreatment of samples is the long-term need to establish an overall correlation between radiocarbon and calendar years. At present this is still a matter for final agreement by the laboratories concerned. Meanwhile, when all possible steps have been taken to ensure the reliability of the date messurements, these can strictly only be compared with one another in terms of radiocarbon years bp. In practice this is often too restrictive but any attempts at calibration must be regarded as approximations for the time being. In this article the lower and upper case notation advocated in Antiquity46, 265, for radiocarbon and calendar years respectively has been followed.