> How so or why so, considering their brain size relative to their body, is not well understood. One factor is neuron size. Bird neurons are around 0.4 the len

> How so or why so, considering their brain size relative to their body, is not well understood. One factor is neuron size. Bird neurons are around 0.4 the length of mammalian neurons, so you can pack in around 8 times the neurons in a given volume. A large parrot has the same number of neurons as a medium sized dog.