The weights I gave were for a chinchilla with an average bone structure. As with humans, some chinchillas do have different bone structures. Chinchillas with a blunt nose and whose shoulders and hips are about the same width, are usually bigger built and weigh more. Chinchillas with a longer pointy nose and whose shoulders are more narrow than the hips, usually tend to be smaller and weigh less.
Being the runt of the litter could also be the answer. Of course I have seen the runts end up being the largest of the litter because they fought the hardest to survive.
Being a little premature could be the answer.
Usually it boils down to the DNA or family history.
Chinchillas that come from a line that has been, over generations, mated with other mutations rather than introducing a good stocky pure standard into the line every 2 or 3 generations will tend to produce smaller and weaker chinchillas with each generation.
Jo Ann
P.S. A "pure standard gray" chinchilla is one who has only grays in it's family history. A standard gray that has mutation colors in it's family history is not considered a "pure standard".
