Oleksiy Mishchenko, of Zurich, Switzerland used a GoPro camero to capture an ostrich chasing his two companions on a a bike ride in South Africa. Per HuffPo:
"It was a little scary at first, but then I thought I gonna fell of my bike from laughter," he wrote in the video's description. "The ostrich didn't have any problem to keep up at 50km/h (31 mph) and apparently they do 70km/h (43 mph) with no sweat."
Ostriches can indeed hit that top speed. According to the National Wildlife Foundation, they can even run for 10 miles straight at a steady 30 miles per hour.
h/t Laughing Squid