About Fishes, Snakes, Alligators and Crocodiles

A series of short but interesting articles from LiveScience.com that answer questions most of us have asked or wondered before:

1. Can fishes hear? They pick up sound through their bodies and heads (where their ear parts are). Fishes also pick up movement through those lines that we so often see along their bodies. Interestingly, also in this short, our facial and head features evolve from the same genes that develop sharks' sensitivity to electricity... and that our ears evolve from fish gills!
2. Do snakes have ears? No ears but they have something attached to their jaw bones that sense low frequency vibrations. And their hissing? Not for communication but assume to warn creatures.
3. What's the difference between alligators and crocodiles? Too complicated for me to summarise so I will just copy and paste them here:

• Snout shape: Alligators have wider, U-shaped snouts, while crocodile front ends are more pointed and V-shaped.
• Toothy grin: When their snouts are shut, crocodiles look like they're flashing a toothy grin, as the fourth tooth on each side of the lower jaw sticks up over the upper lip. For alligators, the upper jaw is wider than the lower one, so when they close their mouths, all their teeth are hidden.
• Home base: Crocodiles tend to live in saltwater habitats, while alligators hang out in freshwater marshes and lakes.