Red-billed oxpeckers on an impala, Kruger National Park, South Africa (© Friedrich von Hörsten/Alamy)

【August 3 2014】This is how social networks operate in the wild. Red-billed oxpeckers, despite the name, will eagerly light upon and peck at any of the grazing mammals of sub-Saharan Africa. But the birds aren’t getting a free ride. They do all that pecking to eat the ticks that feed on the blood of buffalo, impalas, and livestock. It’s a mutually beneficial arrangement: the birds get a meal, the mammals are made parasite-free. But lest you think it’s an equal exchange, know that the red-billed oxpecker has no problem taking a sip of blood from the wound left once a tick is removed. Blech.Explore breathtaking Gallery from the HuluTrip homepage over the past 5 years..