I know it's probably weird to hear this from me, but I scrolled past a tumblr user complaining that human body language is limited because we don't have ears or tails and so on, and this gave me such tremendous pause that I had to come write this:
No, like... pal, no, humans have arguably more body language than many animals, we just put it all in our faces. By specializing into nigh-magical, frankly unnerving levels of facial expression reading we're able to parse amounts of information that I would call unrealistic if I wasn't surrounded on all sides by living examples. That's the reason things which mess with picking up unspoken cues like autism are considered a problem!
(This is also imo why people have to deliberately learn to read other animal body languages: we're so accustomed to finding the communication payload in eyebrow angles and cheek twitches that for quite a number of humans it's a paradigm shift to STOP fixating on the face and look at everything else instead.)