public List<Location> getAllCompatibleActors(Animal actor)
    {
    	List<Location> allactors = new LinkedList<Location>();
	    for(int row = 0; row < depth; row++) {
	    	for(int col = 0; col < width; col++) {
	    		if(getObjectAt(row, col)!=null) {
	    			if(actor.getClass().equals(getObjectAt(row, col).getClass())
		            && actor.getSex()!=getObjectAt(row, col).getSex()) {
	    				allactors.add(new Location(row, col));
		            }
	            }
	        }
	    }
    	if(!allactors.isEmpty()) {
    		return allactors;
    	}
    	else {
    		return null;
    	}
    }