As many of you know, for the last half-dozen years or so I ve been working on an analysis of domesticated ferret, feral New Zealand ferret, black-footed ferret, and wild European and steppe polecat skeletons. As part of that analysis, I ve spent years traveling to American and Canadian museums and universities to collect data. I will be poking around in European museums this fall and hopefully I ll be traveling to New Zealand by next spring for the same purposes. Besides data collected from museums, I have also been accepting the donations of deceased ferrets from various sources, mostly interested veterinarians and sympathetic shelters, but from private sources as well (although no longer). These sources were carefully selected (and the donations screened) to result in a random population , very important in statistical analysis. This is a VERY long-term study because it takes an extended time to build a population of skeletons that can pass the statistical tests that allow them to be accepted as representative of the ferret population as a whole. If this isn't done, the data has no real predictive value. The data I have collected so far has been carefully conserved to prevent it from entering public domain so when the study is completed, it will remain publishable in the scientific media. Outside myself, only 4 people have ever seen the data (but not the complete analysis), and each expert has only seen the part they are concerned with (dental pathology, sexual dimorphism, genetics, and domestication). As I enter the results, I do not look at it in any great detail so observations don't subconsciously influence data collection. I use a double-blind method where the sex, age, neutering, fur coloration, cause of death, source and identity, and other factors of the individual ferret are hidden so bias does not influence measurements or interpretations. Individuals are given random number identifiers, and data collected from individuals are given a second random number identifier. In other words, the ferret Bob C is given a number to hide its identity, No. 7364926. After cleaning and drying, skeleton 7364926 is then measured, but the data are recorded under a second number, No. 040326-01. While the double-blind method makes it difficult for me to assign the results of a single set of measurements to a specific individual, I can see X% albinos have Y% femoral length and Z% dental pathologies. This methodology makes the results gleaned from the analysis hard to dispute, but it makes it extremely difficult to answer the question, What did you discover about my ferret? I try to preserve the double-blind protection of the data as long as possible, but on rare occasion I am forced to break the double blind seal. If those results are made public, they are temporarily deleted from the study so not to influence interpretations or donations. For example, after discussing a problem seen in a ferret, several offers of donations of ferrets with similar problems were made. These could not be used in the study because they were not randomly collected and would have skewed the analysis. Measurements are made with electronic calipers that send results directly to spreadsheets in order to prevent recording error. Bones and teeth are placed in metal measuring jigs built specifically for that purpose to increase precision of measurement. Each measurement, such as the diameter of the femur at midpoint, or the length of the carnassial, is taken at least three times and the totals averaged. If any of the three measurements are not within agreement to 2.5% of the mean, it is discarded and when possible a new measurement taken. At the beginning of each measuring session, measurements are made on several mink calibration skeletons to insure results fall within 2.5% of each other. Measurements were often taken using different methods to check the accuracy of the method. For example, measurements of cranial capacity were taken with tiny lead shot, glass balls, and fine sand, and compared to volumes determined from measurements of endocranial casts. Not all data were measurements; some were recorded as the presence or absence of certain traits, such as the absence of a specific tooth, or the presence of reactive bone at the gum line (an indicator of periodontal disease). Those measurements were easy; they were present or not. Harder to control was the arbitrary measurement of degree of change, such as the amount of tartar (dental plaque) present on a tooth. It was easy to see the difference between little tartar and severe tartar, but try to tell the difference between medium-moderate and heavy-moderate . Using a dozen volunteers, a 1 to 3 or minor-moderate-heavy scale was determined to provide between 95 and 98% repeatability. With a 1 to 5 scale, repeatability by a single observer was only 82% and agreement between observers was only 66%, which illustrates the difficulty of repeating arbitrary observations. The reason for this fanatical obsession with data collection is not because I am particularly anal-retentive (just ask my kids who have seen my lab and work areas I'm known as the Supreme Stacker of Stuff ). Rather, it is because other studies along similar lines have not controlled such variables and the studies have been rejected. For example, several studies of the osteology of ranched mink were used to predict wild mink values, but were rejected when it was realized caging and diet influenced the results. The care and methodology of this data collection process will (hopefully) prevent the results from being discarded from some unforeseen question being left unanswered. This extensive preamble has a specific goal as well; each reader has to understand the data collected in this study is absolutely trustworthy. This is because the data suggest conclusions that can be considered controversial. To be honest, what I discovered took me by surprise. I was so astonished at what I learned about ferret teeth that I went back and measured everything again and I was still shocked. My own personal prejudices were challenged to such a degree that I was forced to the library to research the findings. I could argue interpretations, but I couldn't dispute the data. This study has placed me in an ethical dilemma; the data should be published for other scientists to inspect and comment on, yet the results suggest such profound health implications that for each day release is delayed, harm can come to ferrets. I ve decided to walk the fine line; I will discuss the results, but will still try to preserve the specific numeric data so it can still be published in a scientific journal. Therefore, I won't give the exact numbers here; that is, you won't see something like X individuals have Y pathologies. However, I will be quoting the most up to date percentages that summarize the data, such as X% of the population has Y% of a problem (the individual numbers change almost weekly as I continue to enter additional data, but the percentages have more-or-less stabilized another indication the data is truly random). Some of these data will be published soon, but the rest MUST wait until after the trips to Europe and New Zealand. Those FML members with a strong science background will recognize the controls for data acquisition of this study are of a high standard, equal or exceeding those for most human medical studies. Why is this important? It is the difference between pharmaceuticals and herbal supplements. Are herbals as effective as pharmaceuticals? Some people have the faith they are, but without the type of controlled data acquisition required of the drug companies, you can NEVER be sure. In this case, you might not like what I have to say and you may disagree with the conclusion, but you will not be able to argue the data is tainted, inaccurate, unrepeatable, or invalid. I welcome ANYONE who can offer alternative hypotheses that can effectively explain the data. If your idea fits the data better than my idea, I will readily admit it. In the next few posts, I will be discussing the presence of tartar (dental calculus), periodontal disease, worn teeth, broken teeth, missing teeth, and dental abscesses. There are plenty of other dental pathologies that I have investigated and recorded, but these have the most significance to this limited discussion. With that, on to the dental data. Bob C Questions?: [log in to unmask] Communications? [log in to unmask] [Posted in FML issue 4517]