Nimetic

Larger organisms appear to have evolved from smaller ones - however so have many smaller ones. Additionally, I expect that there are many cases where smaller creatures evolve from larger ones.

On the second point... Evolution simply favours the organisms that survive and breed. The flu virus is successful. The fly is successful - and so on.

On the technology issue. If we put a videophone between every pair of people on the planet, this would not equate to omniscience. Even if we put direct brain to brain connections in place somehow - intelligence does not seem to be an additive effect. One thousant chimpanzees do not add to a human for example, when considering certain conceptual abilities.

...and experiences with large meetings/committees seems to indicate the exact opposite. Large groups can be stupid.

But hey, I leave you with this though. Maybe humanity is already omniscient when considered as a group. It's just a verrrrryyy slow thinker.....