Hi Facundo,

So, I found some papers that deal with this subject. However I didn't know a measure more appropriate. In any way, look the material, mainly the last, which I think that there is an interesting measure to attend your question.

I hope this helps.

http://beheco.oxfordjournals.org/content/early/2014/08/26/beheco.aru125.full

Thanks a lot!

dear Facundo Xavier Palacio i hope next site help you

http://beheco.oxfordjournals.org/content/early/2014/08/26/beheco.aru125.full

https://www.uvm.edu/~ngotelli/Bio%20264/Gotelli&EllisonChapter7.pdf

Thank you Hamdy, Marcelo has already uploaded those papers.