Jellyfish are causing mayhem as pollution, climate change see numbers boom.
Jellyfish have been around for at least 500 million years — they're older than dinosaurs and even trees.
“Science writer Juli Berwald calls them "ghosts from the true garden of Eden. An intelligence of a sort has allowed them to make it through the millennia," she says. "And they're not going anywhere."
In fact, the brainless, spineless, eyeless, bloodless creatures are booming in numbers — and causing mayhem around the world.
Their propensity to breed fast and prolifically means jellyfish can disrupt ocean ecosystems in a flash. And their effects aren't contained to the sea. In places like Sweden, Israel, the US and the Philippines, power plants have been affected by blooms of jellyfish.
"So many jellyfish were swept into the power system … that it shut down the power system through much of this one island in the Philippines," Ms Berwald says."People thought that perhaps there was a coup going on, but there wasn't, it was just the jellyfish."
A human cause
Some scientists think jellyfish numbers are increasing as the climate changes — the creatures reproduce well in warmer waters. Jellyfish also fare better than many other sea creatures in polluted waters, as they don't need much oxygen. Berwald says that can give them the upper hand over predators.
"They can sort of slip into polluted waters, into low oxygen waters, and hide from predation there better than a fish that has a higher oxygen demand," she says.
What can jellyfish tell us?
According to the World Wildlife Fund, most of the waste we produce on land eventually reaches the oceans — everything from plastic bags to pesticides.
Berwald says the lesson from jellyfish is that we need to care for our oceans, and work to tackle pollution.
"Because we are terrestrial creatures we haven't really thought about the health of the oceans," she says."We've considered it as this place that is so big we can never really damage it that badly. The message from jellyfish is that we are."It's quite important that we start doing things more responsibly when it comes to the oceans."
Comments