Saturday, November 25, 2023

A tiny ancient elephant that roamed Sicily 200,000 years ago had babies the size of pet dogs

  • Scientists discovered this ancient elephant fossil on the island of Sicily.

  • They said the elephant shrunk rapidly over a million years because of the constraints of the island.

  • The tiny elephant, and its baby, are on display as models at the American Museum of Natural History.

Imagine a world where you could have an elephant the size of a Shetland pony. Turns out, if you had been alive some hundreds of thousands of years ago, that might've been possible.

Over a hundred years ago, in the late 19th century, researchers discovered the bones of an ancient elephant in Sicily, near Syracuse.

After analyzing the DNA within the bones, scientists were able to construct a picture of how this animal may have looked, which is now displayed in a new exhibit at the American Museum of Natural History, in NYC.

This elephant isn't just, "really cute," Alexandra van der Geer, a paleontologist at Leiden University, in the Netherlands, and a consultant for the exhibit, told Business Insider. It's also, "really an amazing example of extreme evolution," she said.

Extreme elephant evolution


The juvenile Sicilian dwarf elephant. It had hair to help it keep warm.Maiya Focht

These ancient elephants evolved from a common elephant ancestor, the straight-tusked elephant, which was even bigger than modern elephants, weighing in at about 10 tons and standing over 12 feet tall.

In less than a million years, evolutionary pressures caused that mega-elephant to morph into the Sicilian dwarf elephant represented by the fossil here. It was about 6.5 feet tall and weighed 1.7 tons. Its baby, shown in the reconstructions from the AMNH, was even smaller, standing around the size of a mid-sized dog, like a poodle.

Researchers from across Europe, who studied dwarf elephant fossils in order to estimate the animal's body size, said that the giant straight-tusked elephant evolving into the Sicilian dwarf elephant would be like if an adult human shrank to the size of a Rhesus macaque monkey, which is about 1.65 feet tall.

Van de Geer said that this shrinking is especially shocking because it happened on a short time scale, by evolutionary standards. "It is fast. A million years may sound for humans may sound really long. A million years, you can do a lot of things in a million years. But for evolution, that's a short time," she said.

Why did this ancient elephant get so tiny?

Since it was first discovered, scientists have been analyzing different features of the fossils to try to figure out how quickly the elephant went from a gigantic ancient animal into this bite-sized version.

The giant straight-tusked elephants roamed all over what became the European continent around 40,000 to 800,000 years ago, according to the European researchers' study, which was published in the peer-reviewed journal Current Biology.

But when the land masses began to break off or separate because of sea level change, elephant species began evolving in different ways in order to best adapt to their environment. One group of giant straight-tusked elephants moved to Sicily about 200,000 years ago.

From there, a rule of evolutionary biology seems to have taken hold, Ross MacPhee, the curator of the AMNH's Secret World of Elephants, told BI. Species that once lived in mainland areas typically have to adapt to very different environments when they move to islands, and they end up evolving vastly different traits.

For example, MacPhee explained, there's probably a lot less food available on an island and fewer predators. In those conditions, it makes sense to evolve into a smaller species that can eat less to survive. Especially when you don't have to worry about being eaten by big bad predators.

Basically, MacPhee said, "To be on an island, it's bad to be big."

Understanding cases like the Sicilian dwarf elephant helps scientists better understand evolution as a whole, Van der Geer, said. It's survival of the fittest, at the end of the day. "It's a constant fight. Evolution is a fight," she said.

No comments:

Post a Comment