Which bird can run the fastest, up to 70 kph (43 mph)?
And the answer: the ostrich.
As the world's largest and heaviest bird, the ostrich cannot fly, and instead is built for running. Using its powerful legs, the ostrich can sprint in short bursts up to 43 mph (70 kph), and can maintain a steady trot at 31 mph (50 kph).
Ostriches are some of the oddest, yet most well-adapted large birds on the planet. They belong in the Ratite family, which includes birds like emus, rheas, and cassowaries – all believed to have evolved from a common ancestor. While it's likely that their common ancestor could fly, these large birds evolved to life on the ground as it advantaged saving energy, and more evolutionary adaptations followed. This is likely the reason that ostriches are the fastest things that can run on two legs.
Ostriches have the largest eyeballs of any land vertebrate (yes, even bigger than elephants!). As such, they are acutely aware of predators from great distances. If that wasn't enough, their powerful toe-talon can take out or threaten any predator that strays too close. Who thought a bird could be so threatening?
While an ostrich's "fur" can look messy (and a bit goofy), its tufty feathers are actually a structural adaptation: they help keep the ostrich cool, and can be used aerodynamically as rudders when they run at high speeds.
Learn more about these giant birds below.