Brother Against Brother | https://bruteblog.wordpress.com/2016/07/12/brotherswars/ 'Dolphins have possessed brains that are larger and more complex than human ones for more than 25 million years.' Dolphins recorded having a conversation 'just like two people' for first time | http://www.telegraph.co.uk/science/2016/09/11/dolphins-recorded-having-a-conversation-for-first-time/ And the winner is..... (I sound like Tex, I know).
I am sure the dolphins are not being smug when they wave their tales in the water: Opposable phones + human ingenuity = wars, democide, etc. No thumbs + dolphin ingenuity = winnerz
Dolphins do what they do for their survival, it's a tough world out there. They don't do shit for ideological reasons, nor just for fun. Maybe if they had legs and opposable thumbs they'd subjugate us, who knows. As things stand, they are the winnerz.
Mapping the Rising Tide | https://atlanticcenturion.wordpress.com/2016/08/09/mapping-the-rising-tide/ via Vox, mirrors the brother v brother narrative of the bruteblog link in the OP. Maybe living in the deep south west of England will be a bonus. Maybe not. Depends on the city rats. Got to build a little army methinks. Needs must, said General Glosoli.
Much more of dolphins' brain volume is cerebellar, though. Otherwise their brains are actually a bit smaller. Blue Whales do have larger cerebral cortices than humans-about three times as large- but this is to be expected of an animal more than thirty times our size. https://i.sli.mg/rCApMh.jpg