Convergent evolution occurs when different species independently evolved similar features. For example, a bat, a fly and many birds have independently of each other evolved wings and an ability to fly.
This is much the same as human civilizations that hadn't been in touch with each other independently invented writing and the idea of stacking big bricks on top of each other in a pyramidic fashion. (No, there's no conspiracy - just convergent evolution.)
If you see the same pattern in independent groups, there's probably a reason for that pattern. If most flying animals developed wings, that's a good sign that wings are one of the best structures for flying. If most swimming animals like fish and dolphins have a similar, streamlined shape, that's probably the shape that works best in water.
Similarly, if you see a pattern repeating itself across disciplines, that's a sign that there's something to that pattern. Consider this tweet from Naval:
Convergent evolution is a validation mechanism.