Maude Delap Was Born in 1866

VOICES

DOROTHY CROSS

TOM CROSS

FIONA SHAW

WARREN HAYDEN

Maude Delap was born in 1866.

She lived on Valentia island in County Kerry off the south-west coast of Ireland .

She was one of ten children.

She was the daughter of the islands church of Ireland Minister.

She became fascinated with jellyfish.

She caught jellyfish and put them in bell-jars in her fathers house.

She ventured out daily onto the sea drag-netting for plankton to feed the jellyfish.

In1902 Maude Delap succeeded in breeding the jellyfish species Cyanea lamarki.

Ernst Haeckel lived in a house called Villa Medusa.

He was known as the Darwin of Germany.

He was the author of the book Art Forms of Nature.

His first love Annasethe died after one year of marriage. He named a jellyfish after her Desmonema. Annasethe.

Jellyfish appeared very early in multi –cellular animals.

They probably appeared first about 550 million years ago,, in the precambrian period.

The time they were first on the earth what other animals would have lived with them?

Some sponges, flat worm like organisms, maybe even some arthropods relatives of crabs and spiders and things, and they would have all lived in the water at that stage there would have been nothing living on land.

Father and son Leopold and Rudolf Blaschka lived in Dresden Germany.

They pioneered in modelling extremely fragile jellyfish and marine creatures in glass.

The jellyfish that we have today are probably fairly similar to those that existed half a billion years ago.

If you ask any zoologist what the unique characteristic of the jellyfish and corals and anenomes they would say the stinging cells.

The Delap family lived in a house called Reenellen.

They grew gladioli and lilies in their garden to sell.

Local people brought Maude animals and plants they found on the island .

She sent specimens to the Natural History Museum.

In 1930 she found a rare Cuviers whale washed up on the shore.

She buried the whale’s head, in the asparagus patch

When the bones were clean they dug it up.

They photographed the whale skull on a table in the garden.

One day a man found a turtle and brought it to Maude.

He was uncertain whether it was a bird, a fish or some sort of crab…

She sent it live on the train to Dublin.

They put it in a cabinet in the Natural History Museum.

The particular cubomedusan we are interested in here, the most venomous animal on earth, Chironex fleckeri has killed about a hundred Australians in the last hundred years, that’s three times more than have been eaten by sharks and five times more than have been killed by crocodiles . The nematocysts , which are like a little dart that are fired off are the stinging cells. They have developed these stinging cells to capture their prey and that’s the one thing that characterises them , no other animals have stinging cells like that. .

It is a very dangerous animal and it also seems to have a much higher metabolic rate its body functions move much faster a higher metabolism than sypho-medusans that we get in European waters. Also it seems to be capable of swimming much ,much faster.

They have got two distinct parts of their life cycle, a polyp stage where they are fixed to the bottom and a medusa stage where they float around in the ocean.

The adult medusa, the sexually mature medusa, move to brackish water where fresh water mixes with salt water at the end of their life.

In 2001 we travelled to Australia to collect Chironex fleckeri

and study their swimming techniques.

Every morning for days we netted the shallows of the beaches.

Every day empty nets except for small fish and a stray turtle.

Weather had changed earlier that season and water temperatures had dropped.

Instead we gathered a species called Chiropsalmus.

Chiropsalmus is a close relative of Chironex fleckeri..smaller and lass poisonous.

When its utterly dark they are known to rest on the bottom, and then they start hunting again when there is enough light.

So is that essentially sleep, or is it known whether they sleep?

It is not known whether they sleep and sleep is a very difficult idea to tie down anyway

but I don’t think you can describe sleep in something as alien as a jellyfish at all.

There are groups of tentacles at four corners of the animal, that makes essentially the box. And between each group of tentacles then, there is a structure called the rhopalium which has an eye on it, and various more primitive eyes spot s that determine light from dark inside the animal. I should add that only box jellyfish have eyes. The problem with box jellyfish is that they have very complicated eyes, as complicated as our eyes. We wonder then how they’re processing the signals from these eyes, without having a brain. They can see clearly, but then we don’t know what processing power, how big a computer is back there to handle the image, and what they do with it. We know for example that they appear to see dark pier pilings and avoid them, they swim more or less up to a human and swim around it or swim away because it is too big to eat.

Notes on the rearing of the Chrysaora isoceles in the aquarium by Maude J Delap…

On June 21st 1899 I picked up a damaged specimen of the jellyfish Chrysaora isoceles on the shore of Valentia harbour and placed it in an aquarium for examination.

On the following day I saw a numbers of tiny particles moving about in the water and found that they were cilliated planulae which had been liberated from the medusa. Two days later the tentacles began to develop showing that the free swimming planula stage was over and that a fixed hydroid like stage known as scyphistoma had commenced.

I kept a large number of these scyphistomae in an ordinary 12” bell-jar throughout the winter ,about twice a week some fresh sea water was put in a supply of copepods was kept in the belljar but the scyphistomae I found preferred to feed upon small medusae such as sarsia and little ctenophores, pleurobranchia On April the 14th I found a scyphistoma just beginning to start the process of segmentation and kept under observation . The tentacles of scyphistoma were gradually absorbed and the animal changed in colour from white to pink …the next step was to try the experiment of rearing the ephyra up to the adult stage and to see how large the medusa would grow in confinement .By April 22nd the largest ephyra was beginning to assume its adult form ,the circular mouth of the ephyra was now surrounded by four oral arms. Their food supply consisted chiefly of small medusae which were greedily devoured the largest of the ephyra measured on April the 22nd increased in size more rapidly than its companions and proved itself to be survivor of the fittest by eating them on June the 4th….the brown markings on the top of the umbrella began to appear , By June the 13th it had become too large for its bell-jar so it was removed to another the frilled oral arms extended to the bottom of the bell-jar, the colouring of the marginal lobes on the top of the umbrella was now as bright as in a specimen taken from the sea a dark brown colour . About the 8th of July the medusa 13 weeks old reached its maximum growth. The gonads were visible showing quite yellow through the umbrella, the difficulty of obtaining a sufficient food supply owing to the stormy state of the weather and the increased temperature of the water gradually affected the health of the medusa . It began slowly to decrease in size. It spent too a great deal of its time at the bottom of the bell-jar bumping the top of the umbrella upon the gravel instead of swimming round and round at the surface. By August 13th its condition became critical and as it was not likely to live much longer I preserved it in a solution of formalin. .The chief trouble connected with the rearing of this medusa was to obtain a sufficient supply of food. It’s appetite was enormous. The temperature of the water in the bell-jar was often taken and compared to the surface temperature of the sea. The bell-jar stood on a table near a window with an eastern aspect ,sheltered from the sun.

In 1895 a group of British Scientists visited the island.

Maude fell in love with one of them.

He did not fall in love with her.

They visited the great Skellig rock.

Maude sent a box of wild violets from Valentia island to him, every year on his birthday for the rest of his life.

On the second Australian visit in 2002 we succeeded in finding Chironex fleckeri

The jellyfish were gathered by hand to avoid breaking their tentacles

With human swimming it’s swimming with the arms and legs, swimming with the limbs. Now swimming in with box jellyfish is entirely different t, hey are swimming by jet propulsion. So they can very rarely achieve absolutely smooth motion going at the same speed, because when they are sucking in water they slow down, and when they are blowing out they speed up .

The interesting thing is , and this is a primitive feature of jellyfish as well ,that they only have one type of muscles,. In our gut for example we have two types of muscles we have circular muscles going around the gut and we have longitudinal muscles going down the gut. The jellyfish in general the box-jellyfish only have circular muscles , now circular muscles tighten for the contraction phase for shooting out the water but then you have to got to have relaxation, so the recoil or relaxation phase is the jelly bouncing back.

The stomach then ,the mouth hangs down within the bell, it’s called a manubrium , and its very flexible and runs to a stomach at the top of the helmet if you like and the stomach spreads out in the top of the bell and runs in canals which are continuos with the tentacles so if you look at a tentacle in section it looks rather like the human gut.

They buzz along horizontally through the water, until they see or feel a fish or prawn then when they see or feel it they move above the fish or prawn and they drop onto it with their tentacles drawn up in a mass and that way they get maximum amount of sting ,and then take it into their mouth which is hanging down within the bell and you can see the little fish or prawn moving then into the stomach.

WH. He has taken that in nearly completely now.

DC Yes

WH. There you go! Oh, I’ve broken a bit of his tentacle off.

I’m surprised none of them have stung me yet,.

The bigger box jellyfish are more efficient they develop what‘s called now by engineers inertia, and so they cruise while they are inhaling and they keep up their speed, small box jellyfish on the other hand slow down a lot , speed up a lot ,slow down a lot ,speed up a lot , so they are not as efficient.

WH. Get ready .

DC O.K!

WH . He;s not moving that fast is he?

DC. No. He needs to get used to it again doesn’t he?

At the end of the medusan life, medusa spawn and die. That information of the life cycle has been available all through the nineteenth century certainly, and probably a long time prior to that.

Both species were seen to execute a pulse and coast style of jet propulsion. One cycle or pulse of movement was seen to consist of contraction of the bell causing ejection of water, and inversion of the valerian . The contraction seen in all animals resulted in a reduced volume in the bell. The contraction stage was followed by a relaxation phase when the animals coasted refilling the bell as the jelly returned to its original shape and the valerium was once more inverted.

A visual appraisal of the type of movement described above is possible through examination of frames from sequences of Chiropsalmus individual as it moves through one cycle. Only seven animals were used in the final quantitative an analysis.

Each sequence used contained no less than two and a half cycles or pulses of movement .

The use of nodes placed on the body of the animal allowed mathematical interpretation of the position of a given body part at any given time.

Co-ordinates could then be transferred to a spreadsheet for geometrical interpretation of the data. Data within the spreadsheet for a given sequence of locomotion allowed the determination of several parameters of gait, the distances obtained were recorded in pixels as a result of making size measurements a known lateral inter-pedalial distance was available so that measurements could be converted to millimetres. Graphs produced based on the co-ordinates of the nodes during the locomotion allowed numerical description of gait. These graphs having the same horizontal scale display various parameters that change in the course of movement.

To visualise the water currents produced during movement a bright green dye called fluorescin was injected into the bell using a hypodermic syringe. At each contraction a spurt of dye was observed moving quickly out through the velarium when this aliquot of dye reached a certain distance behind the animal it was observed to slow down and roll outwards into a ring structure orientated at right angles to the direction of movement. Hydro dynamic specialists refer to such ring structures as vortices and their formation during motion as vortex shedding . Despite the general similarities of the gaits of the two species the possibility that there were underlying differences between species and even size classes within species became apparent. Statistical testing demonstrated that chiropsalmus ejected a greater volume of water relative to their bell size than chironex.

I fully accept that you can’t know everything…. people choose simple problems because they get an answer. The difficult ones people…scientists tend to avoid because they know they will go to their death without ever getting an answer.

In 1953 at the age of 87 Maude Delap died.