Antarctica is about more than penguins, seals, and spectacular (but disappearing) glaciers. Even the tiniest organisms at the bottom of the world are pretty stunning.
Amphipods lack the name recognition of other wildlife that inhabit Antarctica and the Southern Ocean. But consider them charismatic — if slightly creepy — microfauna. Without them, the Antarctic wouldn’t be what it is. Huw Griffiths, a marine biogeographer with the British Antarctic Survey, said there are 560 amphipod species that have been identified in Antarctic waters, with most hanging around on the seafloor.
“Amphipod crustaceans (sometimes known as sandhoppers) are the second most diverse invertebrate group in Antarctica (after the sea snails) and are found from the beaches right down to the deepest ocean trenches,” he wrote in an email. “This diversity means that they play an equally varied set of roles in the Antarctic food web, they are an important food source for higher predators such as fish, seabirds and mammals, but are also predators, grazers, and recyclers of dead and decaying material.”
Please join me in vibing with these little weirdos that keep the Antarctic going.
Amphipods Come in Many Shapes and Sizes
Amphipods are all crustaceans, but they certainly don’t all take on the same form. They all sport an exoskeleton, but that’s where the similarities end. Amphipods can range from as small as three-hundredths of a millimetre up to 10 centimetres in length. And the shapes! Just look at that dude up there with his oversized oven-mitts for claws and antennae jutting up like some kind of old school TV.
Colours Abound
These little dudes and dudettes don’t just come in different shapes and sizes. They also come in different colours as well. Some are ghostly white, while others are red. And still others, like the amphipod above, are a mix.
“Some of the colours and patterns might be for camouflage, whilst others could be to attract a mate,” Griffiths wrote.
Honestly, this amphipod looks ready for a night out.
Amphipods Aren’t Alone in Their Stunning Appearance
All this colour may seem surprising, given that many live on the seafloor, far from sunlight. Other deep-sea creatures have taken on surprising adaptations far from the surface, including translucence, bioluminescence, and more. But Griffith noted that “these beautiful amphipods are just some of the amazing invertebrates that dominate the Antarctic seafloor, which is often covered in brightly coloured life, including sponges, corals, starfish, anemones, and many more.”
Red Eyes Could Help Sandhoppers See
There’s no denying some amphipods look a little devilish, thanks to their red eyes. But don’t worry, a portal to hell hasn’t emerged in the Southern Ocean (as far as I know). Instead, the eyes could allow them to live in a low- or no-light environment. Griffiths said their eyes could be “especially adapted to detect low levels of light produced by bioluminescence.”
The Spectacular Antarctic Seafloor
Sandhoppers are one of a number of wild creatures found on the seafloor of the Southern Ocean. Scientists have sent robots and even gone diving themselves to see what lives in what, you might think, would be one of the most inhospitable places on Earth. Yet under the Antarctic sea ice, where saltwater temperatures can dip below freezing, life finds a way.
In fact, it doesn’t just find a way; it flourishes. The stunning sea stars, sponges, and other creatures that live on the oceanfloor actually use the ice cover to their advantage. It protects from the storms that can roil the ocean, allowing for unique ecosystems to pop up in technicolor. In that light, amphipods fit right in.
‘A Healthy and Functioning Antarctic’
Every creature has a role to play in a given ecosystem. Whales, seals, and penguins keep the Antarctic, well, the Antarctic. Even penguin poop is a vital resource for the region. (No, seriously.) But it’s the little critters at the base of the food web that make all this life possible in the first place.
“It is important to let people know that a healthy and functioning Antarctica includes the amphipods and other invertebrates playing their important roles in the ecosystem,” Griffiths said. “Understanding these roles and how they might change is more important than ever in the face of climate change in Antarctica, where these cold-water specialists are facing rising temperatures and shrinking sea ice.”
Climate Change Is Altering All of the Antarctic
Indeed, the disappearance of Antarctic ice is a huge concern for all the species that call the region home. Land ice is disappearing at a rapid clip, with 3 trillion tons of ice melting into oblivion since 1992 alone. Sea ice went through a shocking boom and bust cycle last decade, and strange holes known as polynyas have formed at times. It’s all very weird and disconcerting. (Don’t even get me started on what it will mean for coastal locations that will have to deal with land ice melt.)
The Impacts on Charismatic Megafauna Are Bad…
Scientists have poured time and energy into studying the megafauna of Antarctica. Researchers have used satellites and even relied on sensors strapped to seals and minke whales to track how climate change is impacting their habitat. While that’s enough data to pin down exactly what climate change means for the Antarctic’s most charismatic creatures, it’s helping refine a set of possibilities.
…But the Microfauna Are at Risk, Too
Forget not the little guys. Sandhoppers might not get the David Attenborough treatment in documentaries, and they may look better-suited for sushi than being the poster children for conservation. But that doesn’t make their roles any less vital to the Antarctic and other ecosystems where they’re found.