Researchers recently reported a most interesting finding: there is a good correlation between the number of neurons in the cortex and life span when comparing species. This holds up between classes of species, as well for a number of well known exceptions to other associations between physical characteristics and life span. For example, you might compare these results with the relationship between metabolic rate, mitochondrial composition, and life span that largely holds in mammals, save for bats, which are distinguished by their ability to fly. Flight imposes enormous demands on metabolism, and flying species are as a result biochemically quite different from even near cousin flightless species. Further afield in the taxonomic tree of life, birds tend to have far greater life spans than similarly sized mammals, and once again this is probably because of the demands of flight. Nonetheless, this association with cortical neuron count holds up well for birds and mammals alike. Why does this relationship exist? At this point researchers have nothing but educated guesses. I would imagine that we will hear more on this topic in the years ahead, however.
Whether you’re looking at birds