One of nature's greatest acts of partnership 🪺   To give their chicks the best possible start, a female hornbill walls herself inside a tree hollow for months. With only a tiny opening between the, her survival and that of her family rests entirely in her partner's care.    Celebrate 20 years of Planet Earth with us. Find out where to watch the full episode via our link in bio 💚 #PlanetEarth #DavidAttenborough #PE20 #PEIII