[Coral-List] Coral age, DNA and spatial distribution

[di ha]

Greetings all,

I read somewhere through asexual reproduction (ie natural fragmentation) 
that certain individual corals could infact live forever, the parent colony 
dies but fragments with the same DNA survives. (first question, is this 
correct or is a clownfish having a laugh at me?)

My question is this has there been any DNA work done over a reef front 
looking at asexual reproductive colonisation/spatial distribution and then 
the respective age of each coral determined? This might indicate the ability 
of coral species to with stand environmental/anthropogenic impacts that have 
occured over time within that local area.

I realise that the massive favites and favia's are the easiest to age 
(though don't naturally fragment that often, easy and successful with a 
denists drill but that doesn't occur naturally underwater) and the 
acropora's are the easiest to naturally fragment, but aging them??

Just thinking out aloud

any comments would be greatly appreciated

Dion