Warning: SPOILERS for Excalibur
After all these years, Marvel's X-Men comics are finally revealing the real history of the mutant race. Stan Lee originally created the idea of 'mutants' because he was tired of thinking up origin stories. He came up with what he later described as the coward's way out; he hand-waved his latest superhero team as mutants, people who were simply born that way.
Mutants have traditionally been portrayed as the dramatic next "step" in human evolution, with ancient mutants such as Selene and Apocalypse treated as evolutionary precursors. But the evidence is building that this isn't actually the case and that mutants have always existed. In Excalibur #1, Morgan Le Fey - a sorceress who hails from the sixth century - referred to mutants as "witchbreed." This appears to suggest that the history of anti-magic violence - from the Valais witch trials of the 15th century to French legends like the Beast of Gévaudan - was partly directed against mutants.
rewrite the history of the mutant race, revealing that the ancient British order of druids are derived from a clan of mutants who possess the ability to manipulate the ground. A conversation between Rictor and several druids saw them embrace him as their brother, and implied that the druids are a group of mutants whose powers manifest from birth.
Interestingly, this isn't the first time the X-Men comics have featured an ancient tribe of mutants who all possess the same abilities; the much-derided Chuck Austen run introduced the Cheyarafim and Neyaphem, groups who originate from Biblical times and are variously angelic and demonic in appearance. Notice that, in all these cases, the different tribes of mutants originate from distinct geographical locations - and, even more importantly, different ethnic groups. That suggests the gene responsible for mutation - which Marvel calls the X-gene - manifests in very specific ways in each genetic group. Presumably Anglo-Saxons, for example, have a predilection towards ground manipulation. The pseudo-science underpinning the X-Men is suddenly becoming a lot clearer.
But why has there been a boom in the number of mutants in the last 200 years? The answer, quite simply, is that population growth is exponential. The global population is believed to have stood at just 1.6 billion in 1900, and by the end of the 20th century had exceeded 6 billion. If a certain proportion of the world's population have always been mutants, then it stands to reason that the number of mutants would increase exponentially across this same time period as well. According to House of X #4, there were just 17.5 million mutants on the planet at the time of the Genoshan genocide a few years ago. While that number seems high at first glance, it's still less than 0.5 percent of the planet's population, possibly less depending on how you interpret the Marvel Universe's sliding timescale.
This also explains why the varieties of genetic mutation have increased throughout the 20th and 21st centuries, with ever stranger and more distinctive powersets. The age of mass migration - which ran from c. 1850 to the mid-20th century - led to people traveling across the globe, and as a result different genetic backgrounds are mixing. That means many mutants born from the mid-2oth century would inherit an X-gene that shares characteristics from multiple genetic backgrounds. The odds of strange, rarely- or even never- before seen mutations would naturally increase in this context.
The most amusing aspect to all this is that it's currently unclear whether or not Marvel has intended to provide such a fascinating glimpse into the pseudo-science underpinning the rise of the mutant race. Frankly, it's entirely possible writer Tini Howard is simply enjoying telling this story in Excalibur, and is unaware that the comic is subtly rewriting the history of the X-Men.
