Birds usually line the inside their nests with something more delicate and soft. Two of the birds citied in the paper are crows and cockatoos--two of the smarte

Birds usually line the inside their nests with something more delicate and soft. Two of the birds citied in the paper are crows and cockatoos--two of the smartest birds out there. I wager they know what they're doing. I imagine they like the spikes because it helps to deter other nest predators like squirrels and raccoons