Humankind's legacy might be unlike anything the Earth has seen before. According to Sarah Gabbott and Jan Zalasiewicz, both paleontologists at the University of Leicester, our defining testament will be different from today's fossil record, marked by technofossils like fast fashion relics. The duo is exploring what type of fossils humanity will leave behind and what they will tell future beings.
In their book Discarded, Gabbott and Zalasiewicz are trying to understand how the present could be understood through the same means as the past. Manufactured objects such as plastic bottles, T-shirts, and other fast fashion products will form distinctive clues about humanity's existence, with many being only partially recycled and likely to be fossilized.
“We slaughter 75 billion chickens a year. Most end up in landfills. The average broiler chicken has a lifespan of five to seven weeks, and they're deformed—their bones have got osteoporosis,” said Gabbott, as reported by The Times. Future paleontologists may discover a large number of domestic animals raised for food, such as chickens and cows, and will marvel at the diversity of human-made items, including fast fashion products.
In tens of millions of years, Homo sapiens as a species is likely to be long gone, wiped out by a mass extinction it helped unleash. Future paleontologists will question the imprint humans left in sedimentary layers. “A completely new range of fossils and a new style of fossilization are emerging on Earth,” noted Zalasiewicz.
Clothing, which is mostly invisible in the archaeological record, will be a distinctive signature in the fossil record due to humanity's production of materials that are almost completely indigestible. “Humanity produces 100 billion garments each year, and around 60% of those are plastics-based,” Gabbott stated.
The fast fashion model promotes a linear economy of buying, wearing, and throwing away, contrasting with the biodiversity that humans have altered for consumption. Countries like Ghana and Kenya are overwhelmed by open-air dumps of discarded fast fashion items, which future paleontologists will find alongside other puzzles in the sediment.
“Concrete has become the rock of the last 70 years. Over 500 billion tonnes of the stuff has been made. For every square metre on Earth, there is a kilo of concrete somewhere—and most of it is still hanging around. And it's really distinctive,” Zalasiewicz stated. Concrete represents more than half of the mass of what is shaped by humans today, promising it a prominent place among technofossils.
Future paleontologists will see a reconfiguration of the diversity of life due to humanity's impact. “We are making stuff now in numbers that biology doesn't mimic. We're making stuff in ridiculous numbers,” Zalasiewicz said. This includes the production of materials like epoxy resin, which will function like amber and preserve fossils well.
Many materials manufactured by humanity have a greater potential for preservation than organic materials. “There will be an explosion of manufactured materials that will be very hard to destroy and will fossilize easily,” said Gabbott. Plastics, in particular, will be found not only in landfills but also in ocean sediments and practically everywhere.
Humanity is making objects and materials to be durable, to resist erosion, sunlight, abrasion, and not be eaten by animals. Despite recycling efforts, many plastics can be recycled only once, leading to ongoing disposal issues.
Urban constructions, especially those most threatened by rising sea levels combined with subsidence under their weight, will contribute to the future of technofossils. Cities like New Orleans and Amsterdam, which are sinking, will have their substructures survive more or less intact due to sediment accumulation, Zalasiewicz stated. “Once buried and with sediments accumulating around them, the chances of fossilization are really good,” he added.
The number of chickens on Earth far exceeds that of humans, and their consumption continues to increase in forms such as whole birds, fillets, drumsticks, and nuggets. This 'chicken civilization,' as Le Point describes it, may puzzle future intelligent beings who might wonder whether the abundance of chicken bones indicates an avian species that became suddenly invasive or reflects our excessive love for consuming this bird.
The article was written with the assistance of a news analysis system.
