When humans are gone, what animals could evolve to have our intelligence and skills?


Humans are quite unique among life on Earth. As far as we know, we are the only living species to develop higher intelligence, wear clothes, cook our food, invent smartphones, and then deprive ourselves of them when we forget our passwords.

But what if humans suddenly disappeared? What other animals could evolve to have the intelligence and skills to create large, complex societies like ours?

Thanks to modern gene sequencing technology and our understanding of evolution“We’re pretty good at making short-term predictions,” Martha Reiskind, molecular ecologist at North Carolina State University, told Live Science. For example, we can predict that if humans suddenly disappeared tomorrow, climate change would continue to push many species towards drought resilience in order to survive. Species specializing in cold will also continue to struggle, which means that, unfortunately, Polar bears and penguins are unlikely to thrive in the millennia after humans have died out.

Related: What could lead humans to extinction?

“A great thing will be the concept of convergence”, Dougal Dixon, geologist, science writer and author of the speculative book “After Man: a zoology of the future“(St. Martin’s Press, 1998) said Live Science. Convergence is an evolution process by which two independent bodies end up developing similar traits in order to be successful in a particular environment or to fill a particular niche.

The classic example, Dixon said, is the shape of the fish. With their sleek, torpedo-like bodies and stabilizing fins, fish are optimized for life in the water. However, dolphins developed a very similar body plan – and unlike fish, they are warm-blooded, air-breathing mammals with an entirely different evolutionary background.

One feature that makes humans especially good at building and spatial reasoning are our skillful hands, according to research from the Manchester University. In order to fulfill the same ecological role as humans – that is, building cities and dramatically altering our environment – another species would need to develop a similar ability to manipulate objects. In other words, they would need opposable inches – or at least inch equivalents.

Other primates, like chimpanzees (Pan troglodytes) and bonobos (Pan paniscus), our closest living relatives, already have opposable thumbs which they use to craft tools in the wild. It is possible that if humans go extinct, these hominids could replace hominids for us, in the “Planet of the Apes”. There is precedent for this kind of overlap – after all, our species managed to survive the intelligent Neanderthals during the last ice age 40,000 years ago, according to a 2021 study published in the journal Nature. That said, it would likely take hundreds of thousands, if not millions of years of evolution for other apes to develop the ability to create and use sophisticated, human-like tools. To add context to this scenario, the common ancestor of modern humans and chimpanzees lived around 7 million years ago, Previously reported live science.

But any disaster powerful enough to wipe out humans is also likely to wipe out chimpanzees, leaving another candidate for using tools to fill the humans’ niche: birds.

When non-avian dinosaurs Extinct 66 million years ago, mammals have risen to fill many of their vacant niches. If humans were to disappear, it’s possible that birds, the only surviving dinosaurs, could fulfill our roles as the smartest and most maneuverable land animals. Despite stereotypes to the contrary, birds are very intelligent: some birds, like crows and crows, have intelligence that rivals even chimpanzees, according to research published in 2020 in the journal Science. And some birds can use their skillful legs and beaks to shape wire into hooks, according to a famous 2002 study published in Science. Meanwhile, trained African gray parrots (Psittacus erithacus) can learn more than 100 words and do simple calculations, including understanding the concept of zero, Previously reported live science.

Birds can congregate in large groups, and some, such as sociable weavers (Philetairus socius), even build communal nesting sites. Some sociable weaver nests remain occupied by birds for decades, according to a study published in the journal Frontiers in ecology and evolution. However, these arboreal dwellings would not look much like human metropolises.

These imposing termite colonies dot the African savannah. (Image credit: Getty Images)

But there is another group of animals that are extremely adept at manipulating objects with their limbs – all eight.

“Intelligence changes your behavior under the influence of your environment”, Jennifer Mather, a cephalopod intelligence researcher at the University of Lethbridge in Alberta, Canada, told Live Science. By this measure, octopuses are possibly the smartest non-human animals on Earth. They can learn to distinguish real objects from virtual objects, according to a 2020 study published in The Biological Bulletin, and they can even design their surroundings by removing unwanted algae from their dens and barricading the entrance with shells, according to a study published in the journal Communicative and integrative biology. They are even known to live in community, in a way, as the discovery of “Octlantis” off Australia.

Related: How would Earth be different if modern humans had never existed?

However, octopuses are said to have a hard time adjusting to life on earth. Vertebrates have the iron in their blood cells, which binds to oxygen very effectively. In contrast, octopuses and their relatives have copper-based blood cells. These molecules still bind to oxygen, but less easily, and as a result octopuses are confined to water saturated with oxygen as opposed to rarefied air. “They took a metabolism as far as they can go, ”Mather said.

For this reason, Mather believes octopuses and other cephalopods are unlikely to make the transition to earth and take over from humanity as the smartest and most environmentally friendly land animal. His money is on social insects, like ants and termites. “I think the bugs are tougher than us,” Mather said. “Unfortunately, they are also tougher than cephalopods.”

Here’s why: Insects are incredibly adaptable to different types of environments. They have been around for 480 million years, according to the Natural History Museum in London. During this time, they evolved to fill almost every niche imaginable, from flying and burrowing to swimming and even building elaborate towers resembling cities. The organization of ant and termite colonies probably resembles human civilization more than any other non-human species on Earth. Ants are known to grow mushrooms, according to a 2017 study published by the journal Proceedings of the Royal Society B, and termites can communicate over long distances inside their colonies using vibrations, according to a 2021 study in the journal Scientific reports. If humans go extinct, it’s possible these insect colonies will invade the world, assuming they survive climate change.

Of course, this is all speculation; it is virtually impossible to truly predict how evolution will unfold on a geological time scale. “As you go further and further, your accuracy is less clear because there are all these other wonderful things that cause variation,” Reiskind said. These factors include random mutation, sudden extinction events and population bottlenecks, in which a species retreats from the brink of extinction but loses much of its genetic the diversity.

And it’s even more difficult to predict whether another species will develop human-level intelligence or the desire to build cities. Mather thinks it could happen, but not without millions of years of the right selective pressure. Dixon, however, is less optimistic. “I don’t think nature will make this mistake twice,” he said.

Originally posted on Live Science.


Comments are closed.