This is a video of a clam trying to walk and flicking its foot out, freaking out the woman in the background who clearly does not trust what she’s looking at at all. That’s the face of a woman who has watched Alien and isn’t taking any chances. Also, the guy is spouting out a lot of wrong information, but the only thing you really need to know is that this is a clam and the wiener-looking thing it sticks out is its foot. Unlike the wiener-looking thing the guy on the subway sticks out. That thing is most definitely not his foot and you should call the police.
Keep going for the full video, as well as a a video of a clam “walking” along a beach.