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a Scientific American 60 Second Science. I'm Suzanne Bard.

Black rhinos have terrible eyesight.

Even so, these giant African herbivores easily fend

off hungry lions and hyenas.

Their basic body plan has proved to be good enough to survive in a savannah full of large predators, being very large thick skin, big rapier-like horns.

Victoria University of Melbourne behavioral ecologist Rhone plots.

But those protective traits are no match for humans with guns. Today,

the species is critically endangered largely due to poaching. But the rhinos may have an unlikely ally against poachers, the red-billed oxpecker.

The chatty sociable birds often hang out on the backs of rhinos feasting on parasitic ticks.

And actually research has shown that the tick is a favorite diet of an oxpecker.

And if they feed on ticks, that is a good thing.

The birds also get nutrients by picking its sores on the rhinos bodies.

Plots suspected that the rhinos put up with this indignity

because the oxpeckers make loud alarm calls whenever they see humans approach,

giving the rhinos an early warning to flee.

And it's sort of a distinctive rattling but hissing sort of sound.

To test whether the oxpeckers do in fact act as noisy lookouts, Plots and his team

implanted radio transmitters in the rhinos horns. This didn't hurt the rhinos and

allowed the researchers to track the animals.

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