5 Species That Could Dominate Earth If Humans Go Extinct

The human species is the ultimate apex predator. We have only existed for 0.007% of Earth's history, yet we have managed to single-handedly transform the face of the planet, paving over its fields, turning its sand into towering concrete buildings, and crafting weapons that allow us to overpower any other animal. It is both an impressive and tragic feat, as the effects of human activities on the environment have become increasingly damaging, plunging us into a climate change catastrophe and causing countless other species to go extinct.

Whether by climate change, a global pandemic, nuclear warfare, or some other cataclysmic event, our species will one day go extinct too. We will leave behind a world badly scarred from our industries and wars, but it will not be the end of Earth's story... far from it. As we have seen from Earth's mass extinction events in the past, life always finds a way to rebound and flourish.

With human beings out of the way, what species will step into the spotlight? In order to dominate the planet as we do now, they would need to be highly intelligent, capable of adapting to different environments around the world, or better yet, adapting their environment to fit their needs as we humans have done. Numerous species aside from our own are known to use tools and even weaponry, fitting this mold, and the animal kingdom is full of complex social networks strikingly similar to human society. Here are five potential suitors for Earth's next dominant species.

The idea that our closest relatives in the animal kingdom could one day take over in our place is nothing novel. In fact, that very idea birthed one of the most successful science fiction franchises in history. But could Earth ever really become the Planet of the Apes? Chimpanzees (Pan troglodytes) share 98.7% of their DNA with humans, and they demonstrate a trait that has been key to our own species' success: tool use.

Chimpanzees show the most extensive range of tool use in any species other than human beings. With the power of opposable thumbs, they strip twigs of their leaves and use them to probe for anthills and termite mounds for food. They also use rocks to crack open nuts and gourds, and some even sharpen sticks into spears and hunt for small mammals to eat. Chimps pass these skills along through social networks, and will often work collaboratively to maximize efficiency. They behave like humans in so many ways that it's easy to imagine them assuming our position of dominance in the world if we go extinct.

Chimpanzees and other primates could potentially take over urban spaces if humans were wiped out, and might even be able to take a technological jump by picking up the tools we left behind. However, there's one big issue that will likely keep them from succeeding us. Chimpanzees are already endangered, as are around 60% of all primate species, meaning they will likely vanish before we do.

It might seem ridiculous that an aquatic animal could ever dominate Earth like humans do. However, the human lineage originally began in the ocean too, so eventually jumping from water to land isn't inconceivable. On the other hand, it is possible that post-human world domination means water domination. Over 70% of Earth's surface is already covered in water, and sea levels are rising. Of all the aquatic species, octopuses may be best positioned to take power. There are over 300 known species of octopuses, comprising the taxonomic order Octopoda, and they are found in every one of Earth's oceans.

More alien than any sci-fi creation, octopuses have multiple hearts and brains and possess the largest brain-to-body ratio of any invertebrate. They are wickedly clever, famed for their ability to solve mazes and puzzles, and escape containment. Some species of octopus have even been observed using tools, something no other invertebrate does. The veined octopus uses empty shells to make a portable shelter, and the blanket octopus uses the severed tentacles of jellyfish (whose stings the octopuses are impervious to) as a weapon against predators and prey.

The main thing standing in the way of octopuses taking over the world is their short life spans. Most live only a year, and the longest-lived octopus, the giant Pacific octopus, only lives up to five years. Octopuses also lack the social structures of humans, with most being very solitary. However, researchers have observed octopuses communicating by shifting their colors, suggesting some groundwork for building a society.

Of all the human extinction scenarios, none captures the imagination quite like the horrifying threat of nuclear bombs and their fallout. If this were to happen, the world could only be taken over by a creature with the power to withstand significant levels of radiation. It turns out that one of the world's most abundant animals fits this bill. There are estimated to be around 20 quadrillion ants in the world, more than the number of stars in the Milky Way. Ants have shown incredible resilience to nuclear radiation, with populations surviving and even growing in abandoned nuclear sites. On top of that, humans have tried for so long to exterminate ant populations that many species have developed resistance to toxins.

On its own, an ant is not a very formidable creature, but its true strength lies in its colony. Ants are highly collaborative, banding together to gather food and other resources and to protect the colony from threats. Individual ants are able to communicate with each other by rubbing their antennae together, transferring chemical signals to one another.

Ant colonies can be incredibly large and complex, on a scale even surpassing that of human societies. Argentine ants, for instance, are known to form supercolonies with multiple queens and billions of individual ants spread out over hundreds of miles. They are the largest animal collectives on planet Earth, and with their vast and highly coordinated societies, some would argue they're already more dominant than us.

After the mass extinction that wiped out the dinosaurs, it was a group of small, rodent-like creatures that took over, eventually giving rise to mammals and, ultimately, the age of human domination. It would be somewhat fitting then, if in the aftermath of our own species' extinction, rodents again took up our mantle. Rats are in a particularly good position to take over as the dominant species, and that's largely thanks to the helping hand they got from us.

Humans have unwittingly carried rats to practically every land mass on Earth. They now live on every continent except Antarctica and inhabit most of the world's islands, showing the ability to thrive in a vast array of climate conditions. They have become invasive species in many places, building huge populations by outcompeting native wildlife. Although rats don't have very long lifespans, they reproduce rapidly, so their population can grow exponentially in a short period. If any mammal can survive a mass extinction event and rebuild its numbers, it's the rat.

If rats ever do become the dominant species on Earth, they're likely going to go through one very significant change: they're going to get a lot bigger. Larger mammal species will likely be wiped out by any mass extinction, and in their absence, rats could evolve to reach greater sizes and assume an even more dominant position in the ecosystem.

The most likely answer to the question of what species will take over after humans go extinct is unfortunately the most boring one. Humans are one-of-one, and it's likely that luck played a huge role in getting us where we are today. Before modern humans came around, there really wasn't a dominant species to speak of in the same sense. Yes, there were the dinosaurs, but those comprised over 700 species, none of which exercised the degree of dominance over their environment that humans have. It will likely be this way again once we are gone, with numerous species coexisting in the wild, but more extinction events could come after that. When it comes down to the very end, the last lifeforms on this planet will be much like the first ones: bacteria and other microorganisms.

Microbes are already the dominant lifeforms on Earth in terms of sheer number. All of the bacteria on Earth combined would weigh more than all of the animals combined by a considerable amount. They have also proliferated further than any other living thing, thriving in every place on the planet, all the way up into the atmosphere. Due to their ability to survive under almost any conditions, bacteria could be the only things that survive the vaporization of the oceans as the sun begins its death, lingering until the moment our star becomes a red giant and terminates the last life on Earth.