Hope this newbie question is the right question for this site:
Suppose I would like to compare the composition of ecological communities at two sites A, B. I know all three sites have dogs, cats, cows, and birds, so I sample their abundances at each site (I don't really have an "expected" abundance for each animal at each site).
If I count, say, five of each animal at each site, then the A and B are very "similar" (in fact, they're the "same").
But if I find 100 dogs, 5 cats, 2 cows, and 3 birds at site A. 5 dogs, 3 cats, 75 cows, and 2 birds at site B. Then I would say that the sites A and B are "dissimilar", even though they have the exact same species composition.
(I read up on the Sorensen's and Bray-Curtis indices, but looks like they only consider absence/presence of the dogs, cats, etc., and not their abundances.)
Is there a statistical test to determine this? Thanks.