Imagine a world where rhinos and tigers and zebras have been replaced by pigeons, rats and more pigeons.

According to a new study, published this week in PLOS Biology, we're already on our way to that mono-specied future. And it will come at the expense of some of the planet's most iconic animals.

The trouble, the British researchers say, is that as humans develop land for cities and farms, some animals prove better than others at living in them.

Those would be pigeons and rats, as well as sparrows and mice.

For the study, scientists looked at 20,000 plants and animals in 81 countries. They found that animals with wide-ranging habitats, like rats and pigeons, saw their numbers increase where humans changed the land.

Animals with a narrower range, like rhinos, weren't so lucky. Farmlands and cities took a notable toll on their population.

"We show around the world that when humans modify habitats, these unique species are consistently lost and are replaced by species that are found everywhere, such as pigeons in cities and rats in farmland," Tim Newbold, a research fellow at University College London, noted in the study.

By "everywhere," scientists mean that if you traveled to the remotest pocket of east India to catch a glimpse of a Bengal tiger, you'd probably see rats instead.

And if you trek to Alaska hoping to see a polar bear? More rats.

Rat holding a sign that reads, 'Free kisses.' Wherever we travel in this world, there will always be a rat waiting to greet us. (Photo: Jullius/Shutterstock)

And how about those pigeons that photobombed every picture you took from Tokyo to Istanbul to New Delhi?

That's not to say pigeons don't have a place in this world. Nor are they without merits — like, for example, their astounding intelligence.

But we know that a healthy Earth is one that is biologically diverse. There are no bit parts in nature, as every living thing plays a critical role on the planetary stage.

"These findings, by showing how biodiversity typically responds to human developments, have real relevance for global conservation efforts as well as sustainable development strategies," study co-author Samantha Hill notes in the release. "Diversity of life provides resilience to change, and so it is very much in our own best interests to conserve a wide range of species."

Still, there's little chance humans will suddenly stop modifying land on this planet — as our population surges and we rely increasingly on the planet's resources to feed those hungry mouths.

But to avoid wildlife homogenization — and preserve animals that are both culturally and ecologically vital — we may have to adjust conservation strategies to give small-range animals a chance to carve out some space.

Before pigeons and rats inherit the Earth.

As iconic species disappear, pigeons and rats are inheriting the Earth
New research suggests we may find only rats and pigeons where tigers and rhinos once were.