Found a great article on breeding Java chickens:

Why do I care?  Well, Javas were once one of America’s favorite mulch-purpose chickens: considered good eating, good laying, and very hardy.  Today they are one of the dwindling breeds that actually remember how to brood their own chicks (sad, isn’t it?).  At that, brooding is a characteristic that is actively trying to be selected for again.

So what happened?

The usual – those that wanted meat chickens breed for meat and meat only.  Now we have chickens that grow from day old hatchlings to 5.5lb roasters in something like 38 days.  They grow so fast they can’t carry their own weight for more than a few steps.  Those that wanted eggs breed for egg production – and now have birds that produce close to an egg a day if feed enough.  Those that were sloppy in cleaning their birds wanted white pin feathers because they didn’t show as much.  All these thinks took Black Java’s almost to the point of extinction.

Fortunately, the interest by small farmers is recovering heritage breeds has lead to the slow recovery of Javas and many other farm species, like the Highland cattle we raise.  Lots of work to go though!