There’s no need to scan the cosmos to prove the existence of aliens. Look around: the sheer variety of life on this planet already suggests we’re not alone. More intriguingly, the aggressive, predatory behavior of one species in particular hints that Earth may already have been colonized—by invaders who’ve forgotten they’re intruders.

Earth was once pristine, but over time, something changed. The rapid spread of these “foreign” beings has disrupted the planet’s systems, much like an infection overwhelming an immune response. Natural disasters—floods, earthquakes, plagues—may not just be random acts of nature, but symptoms of a planetary immune system trying to restore balance, to expel what it cannot assimilate.

Climate, in this view, isn’t just weather—it’s a test. The species that endure its harshness belong; those that falter are simply unfit, outsiders by design. History’s great calamities seem to follow this pattern. Consider the Yellow River flood of 1887, the Shaanxi earthquake of 1556, the 1931 China floods—disasters that struck densely populated regions with devastating effect. Were these tragedies nature’s way of regulating excess, or something deeper, an ancient code at work?

Yet these events didn’t single out any one people. The influenza pandemic of 1918 swept across borders, infecting half a billion, killing tens of millions. The target was broader, indiscriminate. Perhaps the real “alien” here isn’t a nation or a group—it’s the human species itself.

Despite calling Earth “home,” we seem curiously mismatched with it. If this planet birthed us, why does it feel so hostile? We freeze without fur, so we kill animals for warmth. We lack shells, so we quarry stone for shelter. We can’t fly, so we carve roads and build machines to cheat gravity. Our bodies crave nutrients, but not raw; we must boil, bake, ferment, and refine. Even the ripest fruit somehow demands a blender and a garnish.

And for all our ingenuity, we remain perpetually dissatisfied: needing more space, more comfort, more control. In our quest to tame nature, we reshape it—sometimes gently, often violently—until the world mirrors our desires rather than our needs. We’ve paved rivers, leveled forests, drained wetlands, tunneled mountains, all to make Earth fit our design.

Perhaps Earth resents this. Perhaps what we call “natural disasters” are not punishments, but reactions: the planet’s way of pushing back, recalibrating, healing. And if so, what role do we play in this metaphorical body? Are we its caretakers—or its disease?

In many ways, we resemble cancer cells: multiplying relentlessly, consuming resources indiscriminately, ignoring the larger organism’s needs. We clog its arteries with concrete, bleed it of its minerals, choke its air with smoke. And as with any afflicted body, Earth fights back—not out of malice, but necessity.

Environmentalists speak of saving the planet. But the uncomfortable truth may be that saving the planet, from the planet’s perspective, might not include saving us. The tumor isn’t cured by nurturing it. It’s cured by removing it.

We arrived here from somewhere—whether from the stars, as some myths and theories suggest, or from evolutionary happenstance. But however we came to be, it’s worth wondering: did we ever truly belong?

And if we didn’t, will Earth ever let us forget?