Motion pictures like “Stargate” and “The Matrix” notwithstanding it would not be possible for us to exist on some other planet in some other galaxy.
The reason why is we are not adapted to being anywhere other than where we are. Such an “other place” might meet all of the requirements and specifications for a “world” such as having phenomenological texture and consistency. (1) We might be able to survive “physically” in it, for a while at least. Its climate might be temperate like “England’s green and pleasant land.” (2) Its water might be potable and its food plentiful and nutritious.
Sooner or later though it’s likely its predators would consume us or we would succumb to its viruses or microbes. More pervasively our brains wouldn’t be able to comprehend its various features – its phenomenological structure. Even as we were evading the prospect of getting eaten we wouldn’t be able to navigate it with skill and dexterity, or circumspection and perspicuity.
Not because we aren’t “smart” enough or because we wouldn’t have “brains” during our sojourn there. Rather, neurochemically we simply would not fit with its specifications. The reason why is our brains, with their associated neurochemistry, have evolved right along with the rest of our bodies.
As our precursors developed their craniums enlarged and their brains expanded. Brain cells are “favored targets of natural selection during human evolution.” (3) The evolution of mammalian cortical structure is closely associated with specialization for different sensory capacities (4) such as those outlined at Chapter 1. We developed narrowly-purposed activity centers such as the neocortex, the hypothalamus and the temporal lobe. (5) We also developed specialized neurochemicals such as serotonin. (6) Evolutionary changes in messenger RNA and protein expression levels as well as DNA changes that alter amino acid sequences enabled us to differentiate ourselves from other primates. (7) Without denigrating from its important role the brain is but one component of the complex organism that is the “human being.” The brain enables us, among other activities and functions, to conceive of abstract ideas, to interact with others in group and community settings, and to communicate.
Although there is no evidence one way or the other the reciprocal of this also must be true. It’s amazing the cute (and not-so-cute) creatures of “Men In Black” and E.T., the eponymous protagonist of Steven Spielberg’s movie, lasted on earth for as long as they did. The central theme of both films, though, was one of escape. There came a time when even E.T. found it propitious to decamp to his “green world.”
(1) Hubert Dreyfus would disagree. He believes so long as a world is phenomenologically consistent we would not be able to differentiate between it and our world. Dreyfus, H. & Dreyfus, S., “Existential Phenomenology and the Brave New World of ‘The Matrix’,” http://whatisthematrix.warnerbros.com/rl_cmp/new_phil_fr_dreyfus.html (accessed 2009).
(2) The phrase is from a short poem by William Blake, “Jerusalem.” It is the preface to his much longer work “Milton: a Poem” (1804).
(3) Gilbert, S., Dobyns, W. & Lahn, B., “Genetic links between brain development and brain evolution,” 6 Nat. Rev. Genet. 581 (Jul. 2005); Casci, T., “Brains Under Pressure,” 6 Nature Reviews Neuroscience 822 (Nov. 2005).
(4) Barton, R., “Evolutionary specialization in mammalian cortical structure,” 20 J. Evol. Biol. 1504 (2007).
(5) Falk, D., Redmond, Jr., J., Guyer, J., Conroy, C., Recheis, W., Weber, G. & Seidler, H., “Early hominid brain evolution: a new look at old endocasts,” 38 J. Human Evolution 695 (2000).
(6) Azmitia, E., “Serotonin and Brain: Evolution, Neuroplasticity, and Homeostasis,” 77 Int’l Review of Neurobiology 31 (2007).
(7) Hill, R. & Walsh, C., “Molecular insights into human brain evolution,” 437 Nature 64 (Sep’t 2005).