Intelligence Evolved at Least Twice in Vertebrate Animals
a year ago
- #evolution
- #animal-intelligence
- #neuroscience
- Birds exhibit advanced cognitive abilities despite having brains structurally different from mammals.
- Research suggests vertebrate intelligence evolved independently in birds and mammals, not from a common ancestor.
- Studies using single-cell RNA sequencing show similar neural circuits in birds and mammals but developed differently.
- Birds' brains lack a neocortex but have structures like the dorsal ventricular ridge (DVR) that perform similar functions.
- Historical views underestimated bird intelligence, considering their behaviors reflexive rather than learned.
- Harvey Karten's work in the 1960s showed similarities between avian and mammalian brain circuits, suggesting a common ancestor.
- Luis Puelles later found that avian and mammalian brain structures develop from different embryonic regions, indicating independent evolution.
- Recent studies combine circuit comparison and developmental biology, supporting independent evolution of intelligence in birds and mammals.
- Some genetic and neural components, like inhibitory neurons, are conserved across birds and mammals.
- Intelligence can evolve through convergent evolution, as seen in other species like octopuses, which have entirely different neural structures.