I love jellyfish. It probably has something to do with living inland and only having seen the ocean two or three times in my life, but it's also because there is something just plain fascinating about them. They just look so darned improbable and they have a fascinating life cycle.
The jellyfish that we commonly see in pictures are at the medusa stage. They are round and filled with water and have long trailing tentacles that can sting prey. These come in male and female and make eggs and sperm respectively. When the eggs are fertilized they become a cilliated larvae that settles to the ocean floor and forms a polyp.
Polyps look kind of like strange, alien flowers with finger-like petals. They are usually very small, less than an inch tall and those "petals" gather food for the polyps. Each polyp can break off little peices of itself that are called buds and the buds make tiny little medusa that grow up to look like the original parents. In this way, each fertilized egg can result in a great many genetically identical adults that can then wash up on beaches and sting people.
Links
Here is an article on National Geographic Kids. It includes what to do if you get stung.
Here is a scientific article that shows how jellyfish blooms and algae blooms can interact.
These guys won the Nobel Prize by making glowing jellyfish protiens usefull to other scientists.
Word Of The Day
Nematocysts: The stinging cells of the jellyfish.
Nematocysts: The stinging cells of the jellyfish.
3 comments:
I just saw that movie with Will Smith in it and that is what did him in..
So each bud becomes a separate jellyfish?
How many buds are there on each polyp?
After all the buds are broken off, does the polyp then die?
Do the polyps gather the same kind of food that the mini-medusa will eat later on?
What DO they eat?
Callie: I don't think I saw that movie.
Janna: The polyps, being so small, eat microscopic stuff mostly. You have to remember that there are a lot of kinds of jellyfish and they aren't all exactly the same. Hundreds of medusa can come from each polyp over time but how many the polyp makes probably has a lot to do with its food source. Honestly, I don't know how long a polyp can live. It probably varies. Also, jellyfish eat different things. Some eat fish. Most eat things a lot bigger than what the polyps eat, because most are bigger than the polyps.
I'll do some research and revisit the topic. Those are great questions. Thanks :)
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