"Nowhere else than in these ecosystems do giant sea spiders and marine pillbugs share the ocean bottom with fish that have antifreeze proteins in their blood," says Rich Aronson, professor of biological sciences at Florida Institute of Technology in Melbourne, Fla.
"The shell-cracking crabs, fish, sharks and rays that dominate bottom communities in temperate and tropical zones have been shut out of Antarctica for millions of years because it is simply too cold for them."
But this situation is about to change. "Populations of predatory king crabs are already living in deeper, slightly warmer water," says Aronson. "And increasing ship traffic is introducing exotic crab invaders. When ships dump their ballast water in the Antarctic seas, marine larvae from as far away as the Arctic are injected into the system."
Aronson and his colleagues published their results in the electronic journal PLoS ONE to coincide with the U.S. National Teach-In on Global Warming Solutions on Feb. 5.
Fast-moving, shell-crushing predators, dominant in most places, cannot operate in the icy waters of Antarctica. The only fish there—the ones with the antifreeze proteins—eat small, shrimp-like crustaceans and other soft foods. The main bottom dwelling predators are slow-moving sea stars and giant, floppy ribbon worms.
To understand their history, Aronson and a team of paleontologists collected marine fossils at Seymour Island off the Antarctic Peninsula. Linda Ivany of Syracuse University reconstructed changes in the Antarctic climate from chemical signals preserved in ancient clamshells. As temperatures dropped about 41 million years ago and crabs and fish were frozen out, the slow-moving predators that remained could not keep up with their prey. Snails, once out of danger, gradually lost the spines and other shell armor they had evolved against crushing predators.
Antarctica's coastal waters are warming rapidly. Temperatures at the sea surface off the western Antarctic Peninsula went up 1°C in the last 50 years, making it one of the fastest-warming regions of the World Ocean.
If the crab invasion succeeds, it will devastate Antarctica's spectacular fauna and fundamentally alter its ecological relationships. "That would be a tragic loss for biodiversity in one of the last truly wild places on earth," says Aronson. "Unless we can get control of ship traffic and greenhouse-gas emissions, climate change will ruin marine communities in Antarctica and make the world a sadder, duller place."
karen rhine | EurekAlert!
Further reports about: > Antarctic > Antarctic sea life > Antarctica > Climate change > Populations of predatory king crabs > antifreeze proteins > ecosystems > exotic crab invaders > gas emission > giant sea spiders > global warming > marine pillbugs > sharks > shell-cracking crabs > warming Antarctic waters
Foxes in the city: citizen science helps researchers to study urban wildlife
14.12.2018 | Veterinärmedizinische Universität Wien
Machine learning helps predict worldwide plant-conservation priorities
04.12.2018 | Ohio State University
The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.
Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...
What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...
A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.
The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...
A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.
Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...
Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...
12.12.2018 | Event News
10.12.2018 | Event News
06.12.2018 | Event News
14.12.2018 | Power and Electrical Engineering
14.12.2018 | Physics and Astronomy
14.12.2018 | Physics and Astronomy