I think Uruguayans and Argentinians in general have a lot more in common. Tim Vickery said that although Brazil is in South America, it's pretty isolated to the other South American nations, being the only non Spanish speaking nation (with the expetion of Suriname and Guiana of course as these are more Caribbean than anything else) there and all. Unsurprisingly Neymar seems to be a lot closer to Alves for example.
That makes me wonder how the likes of Verma, Mathieu and Arda get along with the rest of the group given the fact their language/cultural background deviates a little further from the Spanish/Latin nucleus in our squad.