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Mankind will go extinct. There is a high probability certain species of birds, like corvids, will evolve towards greater sophistication.
A. Intelligence
The intellect of corvids, especially New Caledonian Crows, rivals Great Apes, even with a relatively smaller brain.
Interestingly, with New Caledonian Crows we see the existence of meta-tool use, where they can use a tool to modify another tool or save it for reuse, something seen only among humans, chimps, and orangutans. There is also evidence that they transmit local designs via making negative impressions of its shape on a leaf, which may be indicative of a culture. They also show incremental improvements to their tool designs over time. Furthermore, many species of birds are very good at finding solutions to novel problems, or novel solutions to an old one!
This is an example of convergent evolution, and birds and mammals diverged ~300 million years ago from a common ancestor. As noted, even with small brains, though a high encephalization quotient (EQ), the intellect of corvids like magpies and crows rivals greater apes, and while they may lack convoluted, folded cortical structures, I hypothesize their dorsal ventricular ridge (DVR) has more optimized, robust neuronal circuits that rival our cortex. The neocortex of humans is reminiscent of six distinct layers of plywood whereas the DVR of birds is like cloves of a garlic bulb.
B. Genome
Also, the genome of birds are more condensed, and they have approximately 1 billion base pairs with fewer repeat sequences and larger deletion events in which DNA has been expunged over time, perhaps so they can regulate their genes more rapidly to meet requirements of flight. In contrast, humans have a genome of 3 billion base pairs with more repeat sequences. Again, like the brain example, more clutter in our case. On an unrelated note, their lungs are also more efficient than ours.
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