This is how the Sign Languages of the world are related to each other
For example: Portuguese sign language (LGP) was based on Swedish sign language, so these two are very similar, even when their countries are so far away from each other. Most sign languages belong to the French sign language family.
Lea.1717, this is really super cool! Thank you for posting it :D
Would you edit your post and add this at the bottom so people can see a larger image of it? Click for larger version of image. I don't know if you know how to embed links here. Do [Click for larger version of image] (http://i.imgur.com/WofPC5C.png). However, remove the space between the  brackets and the () with the URL.