Jellyfish

[Alan]

My know-it-all daughter has just told me where j/f come from.

Now what she told me sounds a bit far fetched.

Can some knowledgable saltie out there (don't all rush) please tell me what they "KNOW" to be correct.

I may have to shout her a beer on this one, cause I have no idea.

Thanks

[Caryl]

Here is an extract from my article which will be in the next AW...

Life Cycle and Reproduction:

Most jellyfish pass through two different body forms during their life cycle;

Polyp Stage; In this phase the jellyfish takes the form of either a sessile (attached to a rock and unable to move about) stalk which catches passing food, or they are free-floating. The polyp's mouth and tentacles face upwards.

Medusa Stage; In the second stage, the jellyfish is known as a medusa. Medusae have an umbrella-shaped body called a bell. Tentacles hang from the border of the bell.

Jellyfish are dioecious (that is, they are either male or female). In most cases, to reproduce, a male releases his sperm into the surrounding water. The sperm then swims into the mouth of the female jelly, allowing the fertilisation of the ova process to begin. Moon jellies, however, use a different process: their eggs become lodged in pits on the oral arms, which form a temporary brood chamber to accommodate fertilisation.

After fertilisation and initial growth, a larval form, called the planula, develops from the egg. The planula larva is small and covered with cilia (little hairs). It settles onto a firm surface and develops into a polyp. The polyp is cup-shaped with tentacles surrounding a single orifice, looking a bit like a tiny sea anemone. Once the polyp begins reproducing asexually by budding, it's called a segmenting polyp, or a scyphistoma. Budding is the formation of a new organism by the protrusion of part of another organism. New scyphistomae may be produced by budding or new, immature jellies called ephyra may be formed. Many jellyfish can bud off new medusae directly from the medusan stage.

Most jellyfish do not live longer than 6 months, 2 and a half months being more common.

[Alan]

She tells me that on a programme on TV she saw what she was told about the birth of j/f.

It apparently was suggested that when the corals spawn enmasse, the ends of the coral where the expulsion takes place, is the start of a j/f. The end cap if you like.

Now you can see where I'm coming from??

[lduncan]

Nope. Jellyfish don't come from corals.

Corals have polyps, which are where the gametes are released from during spawning.

As Caryl said, most jellyfish have a polyp stage (which is where the confusion may have come from)

Same name, but jellyfish polyps don't come from coral polyps.

Layton

[Caryl]

Hey I got my information from the internet so it must be right

[alanmin4304]

Mother Natures real name is Mrs Google.