For instance, a flock of birds (let's call them the "small beaks") might face a changing climate that kills off its favorite food plant, which produces small, soft seeds that perfectly fit their small beaks.
(its favorite food plant; produces; small, soft seeds that perfectly fit their small beaks) (small, soft seeds; perfectly fit; ) (a flock of birds (let's call them the "small beaks; might face; a changing climate that kills off its favorite food plant,) (a changing climate; kills off; its favorite food plant, which produces small, soft seeds)
its favorite food plant small, soft seeds a flock of birds (let's call them the "small beaks a changing climate
produces perfectly fit might face kills off
small, soft seeds that perfectly fit their small beaks
a changing climate that kills off its favorite food plant,
its favorite food plant, which produces small, soft seeds