Importantly it should work not on species but on stable isotope signals of carbon and nitrogen.

The aim of this exercise is to show that gamma diversity of isotopic signals that represent total isotopic niche is formed by alpha variation observed in several islands , where species was studied, and by beta variation stemming form differences between islands (figure 1 tries to explain that). Note that variation is formed by nitrogen and carbon signals of individuals. At the end we would like to show that there are different types of generalist carabids (figure 2) - some species are very "specialized" at island level but islands are very different (species D) but there are also species which have large variation of isotopic signals everywhere and islands do not differ much. Preferably it could be shown on one drawing with common Y axis showing partitioning in percents as on figure 2.

P.S. FunctDiv.xls invented to calculate RAO does not provide partitioning of diversity.