Q: I read every ferret book I could find in the library. In one of them, the author intimated that the ferrets used for hunting 50 or so years ago were larger and more aggressive than our pet ferrets of today. Is this true or not? A: Sure it's true didn t you know that if it is said in a book, it must be true? BTW, I have a book that says I'm good looking . I've read the same books and occasionally seen the same claims myself. The truth is, there is no way to verify any of them because people were not scientifically measuring the body sizes and weights and publishing them for us to evaluate. The claims are also arbitrary in that we don't know what they mean: are the ferrets twice as aggressive, or ten times? What is meant by aggression? Does it mean the ferrets are more aggressive hunters, or are they more aggressive towards people? As for their size, are they twice as large, or only a third more? Certainly the claims can be true, it is just that we have no way of confirming or understanding them, especially what they mean in terms of our ferrets, normally neutered. You are talking about two different things here: behavioral changes and body size diminution. Lets talk about behavioral changes first. Aggression in ferrets can be caused by dozens of things, including (but not limited to) hybridizing ferrets to polecats, from a lack of training, from improper handling, physical abuse, a lack of security, or even those occasional ferrets that have more wild characteristics than domesticated ones. See the problem? Perhaps they were more aggressive, but the real question is why? , and the sources do not give enough clues to figure that question out. In this case, other sources from the turn of the century suggest ferrets were commonly hybridized to polecats to improve their hunting instincts , and modern genetics studies suggest the same thing, so that might be the reason for enhanced aggressiveness. It is not only possible, it is probable that breeding ferrets to polecats-- called introgression-- created animals that were, in fact, more aggressive, however, we cannot know if that idea is true or not simply because of the arbitrary nature of the statements. What about the size of modern ferrets compared to historic ones? I have a few references that bemoan the practice that some ferret breeders were purposefully breeding smaller ferrets. Most of these references date to the late 1960s to early 1980s, and discuss breeding practices of earlier times. One of the stated reasons was so ferreters would have smaller males to hunt rabbits with. The practice was almost universally condemned (when mentioned) so it is possible the breeders were not mainstream or tinkerers thinking they could breed a better ferret. True or not, ferrets today are generally larger than polecats. One of the things I have notice in my skeletal studies is the degree of sexual dimorphism, the size difference between male and female ferrets, has INCREASED in ferrets compared to polecats, meaning the difference in size between female and male ferrets is greater than the size difference between male and female polecats, something also noted in domesticated ranch mink. It is possible ferrets, during the early part of the 20th century were larger than today, but a close reading of the natural history texts and ferreting books disputes the idea. In fact, based on what I have read, modern ferrets are larger than ferrets from a century or so ago by as much as a kilogram. Personally, I don't think this is because of breeding, but because of diet. No, I am not saying modern diets are better. There are a lot of carbohydrates in most commercial diets, so they are energy rich, shifting the ferret's growth curve so they grow faster and slightly larger. That translates as bigger animals. A similar phenomenon occurs in nature, and is called the maternal effect. It addresses part of another phenomenon called phenotypic plasticity, where the environment influences some aspect of an animal's development or structure. In maternal effect, well-fed mothers are larger, so give birth to larger offspring, while poorly fed mothers are smaller and give birth to smaller offspring; this can proceed for generations resulting in what LOOKS like significantly smaller or larger animals. The advantage of this type of phenotypic plasticity is that smaller offspring require less food resources, so survive better in marginal environments. It also makes ranched mink bigger so they have larger pelts for the fur industry, which is where the use of carbohydrates to make bigger offspring was first noted. Oh, one last comment: there is zero evidence that larger offspring are healthier, and a burgeoning body of evidence suggesting both extremely small and extremely large animals (representing the limits of phenotypic plasticity) have more health problems in the long run. Q: Okay.. my question is.. why are you abbreviating Black-Footed Ferret, BBFs.. and not BFFs??? or is it something else? A: BBF stands for Big Bob Ferret , ok??!! It was a dyslexic moment. My post exceeded the FML line limit, so I went back and used the replace edit function to replace black-footed ferret with BFF to help shrink the length of the lines. However, in a dyslexic moment, I wrote BBF by accident and replaced every black-footed ferret with it. Since I m dyslexic, even though I reread the post several times, I never caught the goof. This is why, although my name is Robert, I go by Bob. This wasn't the worst that I've done in a dyslexic moment. Once, I wrote a note to a girlfriend named Adell, and spelled it Della. Boy, THAT has hard to explain! It is better in the long run after I lost an Adell and gained a Della. Oh yeah, MUCH better! Bob C Communication? [log in to unmask] Questions? [log in to unmask] [Posted in FML issue 4572]