It’s the African oxpecker bird that feeds off the backs of hippos, zebras and elephants. People used to think it was the perfect symbiotic relationship (what’s called mutualism – a relationship where both species benefit), with the oxpecker snacking on the irritating ticks. However, on closer inspection, the reality is that the birds are actually sucking on the blood from the open wounds created by the ticks (…a possible parasitism relationship where one species nourishes itself to the disadvantage of the other?) Yes, the oxpecker eats a tick or two in the process, but perhaps that’s collateral damage or a refreshing palette cleanser. The oxpecker does however provide the animal with an inbuilt alarm system. It screeches loudly when started and might just give enough warning to its host that a predator is not far away. If the warning serves no benefit, then perhaps its a symbiotic commensalism relationship, where one species obtains food or shelter from the other without harm to its host.