While ubiquitous in nature, melanin, which provides the coloring found in hair, skin, eyes, feathers, scales, etc., is an especially important substance as far as the human condition is concerned. Melanin’s role in determining skin color makes it the primary physiological basis for racial differentiation among humans; in fact, entire civilizations have arisen and fallen due to perceptions and misperceptions concerning its nature and signification.
It is for this reason that we have chosen to focus on melanin’s lesser known, biological role and how being more pigmented, i.e. darker skinned, or put oppositely, being less intensely de-pigmented, i.e. less light skinned, may have a unique set of health benefits which have been repressed or misrepresented over the course of history, in order to fuel race-based constructs.
Melanin, after all, has a diverse set of roles in various organisms. From the ink of the octopus, to the melanin-based protective colorings of bacteria and fungi, melanin offers protection against a variety of threats: from predators and similar biochemical threats (host defenses against invading organisms), UV light, and other chemical stresses (i.e. heavy metals and oxidizing agents). Commonly overlooked, however, is melanin’s ability to convert gamma and ultraviolet radiation into metabolic energy within living systems.
Single-celled fungi, for instance, have been observed thriving within the collapsed nuclear reactor at Chernobyl, Ukraine, using gamma radiation as a source of energy. Albino fungi, without melanin, were studied to be incapable of using gamma radiation in this way, proving that gamma rays initiate a yet-unknown process of energy production within exposed melanin.
Vertebrate animals, in fact, may convert light directly into metabolic energy through the help of melanin. In a review on the topic published in 2008 in the Journal of Alternative and Complementary Medicine, titled "Melanin directly converts light for vertebrate metabolic use: heuristic thoughts on birds, Icarus and dark human skin," Geoffrey Goodman and Dani Bercovich offer a thought-provoking reflection on the topic, the abstract of which is well worth reading in its entirety:
Pigments serve many visually obvious animal functions (e.g. hair, skin, eyes, feathers, scales). One is 'melanin', unusual in an absorption across the UV-visual spectrum which is controversial. Any polymer or macro-structure of melanin monomers is 'melanin'. Its roles derive from complex structural and physical-chemical properties e.g. semiconductor, stable radical, conductor, free radical scavenger, charge-transfer.
Clinicians and researchers are well acquainted with melanin in skin and ocular pathologies and now increasingly are with internal, melanized, pathology-associated sites not obviously subject to light radiation (e.g. brain, cochlea). At both types of sites some findings puzzle: positive and negative neuromelanin effects in Parkinsons; unexpected melanocyte action in the cochlea, in deafness; melanin reduces DNA damage, but can promote melanoma; in melanotic cells, mitochondrial number was 83% less, respiration down 30%, but development similar to normal amelanotic cells.
A little known, avian anatomical conundrum may help resolve melanin paradoxes. One of many unique adaptations to flight, the pecten, strange intra-ocular organ with unresolved function(s), is much enlarged and heavily melanized in birds fighting gravity, hypoxia, thirst and hunger during long-distance, frequently sub-zero, non-stop migration. The pecten may help cope with energy and nutrient needs under extreme conditions, by a marginal but critical, melanin-initiated conversion of light to metabolic energy, coupled to local metabolite recycling.