160°F is a kind of magical temperature for most pathogens. There are some strange thermophiles that survive boiling water, but they are, well, strange, and rare.
I used to do a lot of work on composting and when done right (which is rare), the stuff hits 160°F at max T and then cools off again because the stuff dies.
And 165°F adds a Marge N. Overa in case part of the bird isn't at that T.
It's (160°F) also 71°C, which is handy to know if you ever find yourself in the rest of the world.
Our oven is new to me, I've rarely used it, it has convection settings, but I'm just not sure it's at the indicated T. The wife is redoing the kitchen and we're replacing it with a Bosch inductive stove which should be more reliable.
160 isn't really special. 130 or so is the key temp for most food-borne pathogens that really have the potential to impact humans. Above that temp, the pathogens of highest interest
start to die.
Note the bold. That's when they
start to die. At that temp, it will take a LONG time to kill enough of the pathogens to actually keep you safe. At 160, they'll die basically instantly.
A good reference is here: http://www.douglasbaldwin.com/sous-vide.html#Safety_Summary
This is the key with sous vide. By tightly controlling temperature
and time, you can get safe food at lower temperatures than what is typically suggested (160 for poultry) by increasing time.
The issue is that in an oven, this is hard to do. Water [in a sous vide bath] transmits heat to food extremely well. Air, however, does not do so very well at all. So in an oven, it's really hard to know exactly what temp all parts of the bird are at and be sure they're at that temp long enough to be safe. So the "easy" answer is to just make sure you hit 160+.
But 160 is not some magic temp. It's just the temp at which the pathogens are being killed so quickly that you can assume that if you've hit that temp, they're ALL dead.