Microsatellite standardization and evaluation of genotyping error in a large multi-partner research programme for conservation of Atlantic salmon (Salmo salar L.).

Microsatellite genotyping is a common DNA characterization technique in population, ecological and evolutionary genetics research. Since different alleles are sized relative to internal size-standards, different laboratories must calibrate and standardize allelic designations when exchanging data. This interchange of microsatellite data can often prove problematic. Here, 16 microsatellite loci were calibrated and standardized for the Atlantic salmon, Salmo salar, across 12 laboratories. Although inconsistencies were observed, particularly due to differences between migration of DNA fragments and actual allelic size ('size shifts'), inter-laboratory calibration was successful. Standardization also allowed an assessment of the degree and partitioning of genotyping error. Notably, the global allelic error rate was reduced from 0.05 ± 0.01 prior to calibration to 0.01 ± 0.002 post-calibration. Most errors were found to occur during analysis (i.e. when size-calling alleles; the mean proportion of all errors that were analytical errors across loci was 0.58 after calibration). No evidence was found of an association between the degree of error and allelic size range of a locus, number of alleles, nor repeat type, nor was there evidence that genotyping errors were more prevalent when a laboratory analyzed samples outside of the usual geographic area they encounter. The microsatellite calibration between laboratories presented here will be especially important for genetic assignment of marine-caught Atlantic salmon, enabling analysis of marine mortality, a major factor in the observed declines of this highly valued species.

A Zoologist with a Taste for the Past: The Earl of Cranbrook’s Contribution to Zooarchaeological Research in Southeast Asia

The Earl of Cranbrook (V) (then Lord Medway) was fi rst introduced to archaeological research in 1958 when he participated in excavations at the Niah Caves, Sarawak Borneo. In that same year he published a paper entitled ‘Food bone in Niah Cave excavations (-1958)’ in the Sarawak Museum Journal. Unbeknownst to him at the time, his individual and intuitive research was on a par with, if not methodologically ahead of, burgeoning studies in the fi eld of zooarchaeology that were taking place at leading academic institutions in Europe and the United States. This paper recounts and lauds the signifi cant contributions the Earl of Cranbrook has made to the establishment and furtherance of a discipline over more than 50 years.