But they look so cute, and...and, innocent!Hey, it isn't just the amazon. Have you ever been spiked by a bluegill or green sunfish? Channel catfish can nail you pretty good, too.
Seriously, though, thanks for calling this to our attention. I love seeing and thinking about these adaptations. Did you know kuhli loaches have a retractable spike under each eye that they can extent when they're attacked? Most fish predators prefer to swallow their prey head-first, and it's almost impossible for them to gag down a kuhli. I love knowing stuff like that. I never realized that the lowly cory-cats were so formidable! It makes keeping them that much cooler.