Question: i asked you this in the chat zone but you had to go so can i ask you now what do jelly fish do?

Lydia Bach answered on 21 Nov 2014:

Hey M&M,

oh yes I remember!
Lets see: jellyfish are free swimming animals which can be found in all oceans around the world. They use their bell for moving and stinging cells to catch prey. Stinging cells explode when they are triggered our touched. The sting comes from the toxins contained in them.

Check out this box jelly, its a veracious and efficient predator:

https://www.youtube.com/watch?v=pYUZxS1bZR4

Jellyfish have existed for millions of years and have remained pretty unchanged. Scientists think the first of their kind roamed the ancient oceans as long as 500 million years ago, maybe even more. They were amongst the first organisms that were made up of a larger numbers and with different functions (like digestive cells, tissue cells, reproductive cells and so on).

Jellyfish also form coral reef when they are in their non moving stage. They settle down as polyps filtering food out of the water pretty much upside down like the mobile jellyfish would swim.

Check out the pictures here:

http://darwinsreef.pbworks.com/w/page/66265215/Coral%20Polyp

Scientists think that there are more jellyfish on our beaches and in the oceans, because the conditions they need are better for them now.
Jellyfish like nutrient rich water, which comes from runoff of towns or even fields. Warmer oceans also suit them very well… Some scientists also think that their larval stages are not predated heavily anymore, because we have less larger fish. All of that probably causes greater numbers of jellyfish on our beaches.