Parrots pack twice as many neurons as primate brains of the same mass

Summary

I was doomscrolling Reddit at 1am (as you do) and someone had posted a video from the New Zealand Transport Agency. Road workers near a tunnel by Milford Sound kept finding their traffic cones in weird places. Dragged into the road, rearranged, sometimes actively rerouting traffic. Nobody could figure out what was going on, so they checked the cameras. Kea. Native to New Zealand, these big parrots are usually seen on the route to Milford Sound harassing tourists. A flock of them is officially called a "circus" or a "curiosity" -- whoever named them clearly met one. The footage showed them just... casually shoving cones around a construction site. But here's the insane bit -- workers said the kea would listen for cars coming through the tunnel BEFORE moving the cones, timing it so the cars would have to stop. Why? Because stopped cars mean humans getting out. Humans getting out means food. These birds are smarter than some adults I know. Move cone → car stops → human gets out → human feeds me. They independently invented toll booths. The transport agency's solution was equally funny. They switched to heavier cones the birds couldn't move, and then -- I'm not making this up -- they built "kea gyms" by the roadside. Puzzle stations and contraptions to keep them entertained. A government agency literally built a playground for parrots because they were too smart for traffic management. Honestly, I'm fine with my tax dollars going to this. Obviously now I had to know -- is this the smartest bird in the world? And hold on, how do you actually measure how smart a bird is? So I whipped out ChatGPT and Google Scholar and here's what I learned. How do you give an IQ test to a bird? Turns out there's no single test -- researchers have come up with a bunch of different experiments over the years, each designed to measure a different type of intelligence. Some of these I'd fail too tbh. First up, the mirror test. You stick a coloured mark on a bird somewhere it can only see in a...