Earthworms have epic sex and grow to huge sizes

They also live in herds and perform feats of engineering that have baffled scientists for decades

This week, an earthworm called Dave has been exciting the British public.

That is because Dave has been measured at 16in (40cm) long, making him and her (we'll explain that later) the longest earthworm recorded in the UK.

But, and here is a phrase you may never have expected to read, earthworms get even more interesting.

Here are five more startling facts.

Earthworms grow much, much bigger

Dave the earthworm may have impressed the UK, including the researchers who measured him at the Natural History Museum in London.

But at 40cm, he is a slip of worm compared to others around the world.

There are a few species that can grow more than 3ft (1m) long.

Measuring the size of an earthworm is difficult, as their soft bodies naturally extend and contract, and it is easy to inadvertently stretch specimens.

But the largest earthworm in the world may be the giant Gippsland earthworm of Australia (Megascolides australis), a rare species found in just five locations.

According to the Encyclopedia of Endangered Species, individuals reliably reach 6.6ft (2m) long, with a diameter of 4cm. Another species, the African giant earthworm (Microchaetus rappi), is also reported to reach lengths of 6.6ft (2m) or more.

Giant earthworms create mysterious mounds

Earthworms are renowned for shifting soil. But in South America, one species has been identified as the creator of a beautiful and mysterious series of mounds.

The Surales is a landscape of green mounds and deep pits, organised in intricate and regular patterns.

They span many square kilometres, but these mind-boggling mounds were built by humble earthworms that grow more than 3ft (1m) long.

Even the way the earthworms build the mounds is a little odd. Over decades, the Andiorrhinus worms have stuck to rigid eating habits.

Read the full article here