When Homo sapiens self-destructs and takes much of the world with it, what will remain? Lego and tardigrades, predicts Sandy Edwards, who is among many readers to nominate the mighty, tiny tardigrade. Edwards, from St Andrews in Scotland, says: “Survivalists! When it comes to the end of the world, they, and Lego, are all that will remain!”

Mirko Tosoni, based in Amsterdam, is another fan. “They are the only one who ever survived five mass extinctions on Earth – talk about resilience! They also live in the most uninhabitable places, from the moon to the deepest sea, and yet are around us every day, too, in the moss of your garden, for example. Don’t we all need more resilience in this messed-up world we live in?”

We are all feeling vulnerable at the moment. In gloomy geopolitical times, when we feel small and powerless, we are drawn to similarly small species whose resilience carry a message of hope.

And none are more resilient than the tardigrades, a phylum of eight-segmented micro-animals that measure less than a millimetre long.

Our nominee, the 0.5mm-long Milnesium tardigradum, survived in outer space when plonked there as part of a European Space Agency experiment. Tardigrades can endure radioactivity, most cancers, extreme cold, scorching heat, zero gravity, being shot from a gun and being trapped in a freezer for – wait for it – 30 years.

Most remarkably of all, this astonishingly tough invertebrate is also incredibly cute. When the German zoologist Johann August Ephraim Goeze discovered these animals in 1773 he named them the “little water bear”. They’re also affectionately known as moss piglets, as their cute, plump forms can often be enjoyed if moss or lichen is put under a microscope.

Their name comes from the 18th-century Italian scientist Lazzaro Spallanzani, who named them “tardigrada” (“slow steppers”) after their plodding walking style on their four pairs of legs.

Like us, M tardigradum is an omnivore; unlike us, it grazes on algae while also predating rotifers, nematodes and other smaller tardigrades.

The secret to its resilience is its ability to suspend its metabolism and halt the ageing process. Tardigrades evolved in water, and require a film of water around their bodies to enable them to survive. If they are exposed to freezing or drying, they enter a desiccated state called a tun. In this state, they can survive for many years – instantly reviving when they encounter water.

With such superpowers, tardigrades have survived all five great extinction events. They’ve been making a living on Earth for 600m years, and they are already a hugely popular choice among us latecomers to the existence party. Milnesium tardigradum is found in all kinds of habitats, all around the world, and has gathered eloquent nominations from readers in France, the US, Canada and Britain.

Whatever humanity hurls at them, the tardigrades will shrug it off and continue their plodding long after we are just a thin layer of plastic in the soil.

So vote indestructibility, vote cute moss piglet, vote Milnesium tardigradum.

• Between 24 March and 2 April, we will be profiling a shortlist of 10 of the invertebrates chosen by readers and selected by our wildlife writers from more than 2,500 nominations. The voting for our 2025 invertebrate of the year will run from midday on Wednesday 2 April until midday on Friday 4 April, with the winner to be announced on Monday 7. Read the other fantastic nominations here.