Viral: Can you recall ever witnessing a hippo brushing its teeth? It's the most fascinating thing we've seen today, and neither have we until now. The zookeeper in a video that went viral and was widely shared on Twitter was assigned the unusual duty of cleaning the mammal's teeth, which can reach a length of 1.5 feet.

The man crosses over the body of water and rolls up his sleeves, preparing to dive in. With a willing smile, the 1,500kg hippo puts its head on the rock. Using his bare hands, the brave zookeeper massages the hippo's gums before using an enormous toothbrush to give it a thorough scale and polish.

Hippos have up to 40 teeth, and most of the time, fish and birds are the ones who brush their teeth. The animal appeared to be rather happy to get some human aid based on his response. Many people commented on the strangely pleasant video. One laughed sarcastically and was eager to learn more about the position and how to apply. With so many likes, the video has had 20.2 million views since it was uploaded.