Giant fossil ant’s clues to a warmer past

Remains found in America's Wild West indicate giant insects flourished there in high temperatures 50 million years ago.

At two inches long, they may not be on the same scale as the monsters of sci-fi, but the remnants of ants discovered in Wyoming, in the western states of America, are being described as ‘giants’.

Scientists looking through drawers in a museum found fossils that show that ‘monstrously big’ ants were flourishing in America 50 million years ago.

The team who discovered the new ant have named it Titanomyrma lubei – ‘titan’ for its size, myrma for the Greek ‘myrmex,’ or ant, and ‘lubei’ for the fossil collector who discovered the specimen, Louis Lube.

The Wild West, indeed the whole planet, was a very different place when these ants, described as ‘the size of hummingbirds’ were on the prowl. For one thing, the American continent was linked to Europe by a ‘land bridge’ in the Arctic – similar remains have been found in Germany and scientists are now speculating on whether they trekked from America to Europe or the other way.

Another major difference between then and now is the higher temperatures. When these globe-trotting insects were around during the early Eocene (50 million years ago), the sea levels were low and even the far north was a temperate zone, allowing the ants to make their journey.

And there was more oxygen in the atmosphere – which is what allowed insects, including ants, to grow to such large sizes. Most insects breathe through a system of many tubes – or tracheae – in their skin connected to the air supply. As they grow bigger they need more and more tubes, and there’s a limit to how many are practical – unless the quality of the air improves.

One scientist said of the discovery: ‘This ant scurried about an ancient forest in what is now Wyoming when the climate there was hot like the modern tropics. All of the closely related fossil giant ants have been found in Europe and North America at sites that had hot climates.’

Environmental challenge

Insects are a very ancient group of creatures – scientists believe they originate from well before the dinosaurs. And they can survive in tough environments.

These new discoveries are offering clues about when, where and how ants found suitable habitats, it’s true. But how they survived and how life forms were affected by previous periods of global warming is an area of scientific inquiry that could help even humans adapt during the earth’s current period of climate change.

You Decide

  1. 'No. Sorry. Insects are just creepy crawlies – I'm reaching for the flyspray now.' Is this you?
  2. 'Insects flourished before man arrived on the scene, they'll still be here when we've gone.' How likely is this? Do you care?

Activities

  1. Imagine you have discovered a species unknown to science – describe it, perhaps draw it, and give it a Latin name based on characteristics and circumstances of discovery.
  2. Research why ants are such a successful species, and write a short essay on their characteristics.

Some People Say...

“Ants are far superior to humans.”

What do you think?

Q & A

They're not really giants are they?
Well, at 2 inches, they are as big as the biggest ant queens we currently know about in some tropical areas of Africa. Because the biggest ants seem only to live in the very hottest areas, scientists are trying to fathom why this is - but the new fossil discovery fits the pattern.
What about other insects?
Well, fossils of huge dragonflies and other large prehistoric insects have also been found previously. They probably got bigger because of the oxygen levels as well. The only exception is cockroaches, which are bigger today than they were in the past.
I thought cockroaches were going to take over the planet.
Ants are more numerous, they have the biggest brain to body ratio of any species and they work brilliantly in social groups to dominate an area.

Subjects

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