Q: What the fuck is a walrus? A: A tusked sea tuber
Above is an image of a walrus and below is an image of two sweet potatoes
I ask you to note the general similarity in appearance between the two. Thus, knowing next to nothing about taxonomy, I propose that a walrus is obviously a large mobile tusked potato-like life form that dwells in the Arctic seas. No need to thank me for this keen observation, I give it for free.