Chook observes fox bounding from cover and charging for it. Chook screams and makes a run for it.
Chook owner is cleaning coop when (spider/snake/rat) drops from rafter and plops down on their head. Owner screams and makes a run for it.
Same cephalochordate-vertebrate lineage, same shared tetrapod ancestor, same primary dopaminergic pathways (emotion). And quite a bit of conserved DNA shared between us (~30%).
The most telling difference (as has already been mentioned) is our ability to sit around later and make up overripe BS about just how scared we were so as not to think about just how scared we should have been. Whereas chooks react and get back to business. That being said, it is difficult to understand their chortling in unison (have heard this on monitor on several occasions) as being purely instinctual as it appears to be a response to indicate they are pleased to be safe, warm, well fed - to have `survived' another day, rather than a song that somehow increases the chances of survival itself.
The behavior of the chooks that resulted in my observing them much more closely occurred when they were still pullets, a couple of summers ago. One girl had caught a very large, hard shelled beetle (almost as big as her head). Usually, if one pullet had grabbed up something big and yummy (frog/toad/snake/vole) the chase was on and it got about as intense as a crowded buffet with only one steak left in one pan (behavioral parallels, anyone?).
However, as she worked away at pecking through the back of the bug, the two girls closest to her kept up their stripping of seeds from the grass nearby. Just when she managed to pull off one of the wing covers and stick her beak into the guts, the other two pullets rushed her and one managed to grab the partially eviscerated, but still struggling, insect, and the usual chase ensued.
I hypothesize that chooks are capable of at least rudimentary planning. In this instance: Conspiracy and malice aforethought.
To go one step further (off the deep end) it is frightening to note that we have been genetically engineering Gallus Domesticus for a Very Long Time, we eat them, we steal their eggs, we process them into this and that. Someday, someone is going to breed the wrong wrong chooks too close the the reactor over in Reform, MO. and we'll have a chook that can hold a grudge. At present there are ~28 billion chickens, but only ~6 billion humans - watch out!
Barg's Mrs. Nezbitt might only be the beginning...
https://www.backyardchickens.com/forum/viewtopic.php?id=17217
`henpecked? Would that be actually, or just a state of mind?'