The 400 Eels of Sigmund Freud.
What did Aristotle say about eels?
Aristotle tells us that ” the eel is neither male nor female and can engender nothing ” (H. A. 538 A 2), “nor was an eel ever found supplied with either milt or spawn, nor are they when cut open found to have within them passages for spawn or for eggs” (ib. 570 A 16).
Do eels have testicle?
People caught eels in brooks, rivers, lakes, the sea. They also caught them, inexplicably, in ponds that dried out and refilled each year, and that had no access to other bodies of water. They couldn’t help but notice that the creatures seemed to have no ovaries, no testicles , no eggs, no milt.
What did the eel want to do why couldn’t he do it?
The young man, whose name was Sigmund Freud, eventually followed his evolving questions in other directions. But in Trieste, elbow-deep in slime, he hoped to be the first person to find what men of science had been seeking for thousands of years: the testicles of an eel.
What did Freud do with eels?
For four weeks in what felt like an exercise in futility, Freud dissected hundreds of eels to try to locate testes “All the eels I have cut open are of the tenderer sex,” he would report until around eel number 400 when finally, he found the prize: gonads, buried in the abdominal cavity.
Why can’t eels breed in captivity?
As the fish approach their destination this mechanism is deactivated allowing the development of these organs to continue and the gametes (eggs and sperm) to form. In captivity (or in European waters), eels do not breed naturally because of this inhibition of the development of their
reproductive organs
.
Do eels mate for life?
Scientists are a step closer to solving the mystery of one of the great animal migrations. Each autumn, eels leave European rivers to travel across the Atlantic Ocean to breed for a single time, then die.
What do you mean by eel?
Definition of eel (Entry 1 of 2) 1a : any of numerous voracious elongate snakelike bony fishes (order Anguilliformes) that have a smooth slimy skin, lack
pelvic fins
, and have the median fins confluent around the tail , compare american eel. b : any of numerous other elongate fishes (as of the order Synbranchiformes).
Why is an
electric eel
not an eel?
Though commonly referred to as an eel, this fish is not considered a “true” eel. While true eels are classified in the order Anguilliformes, the electric eel is actually in the order Gymnotiformes, the knife fishes. Knife fishes have no dorsal fin and a long, extended anal fin.
Do eels have sperm?
To-day on examining the testis of a male eel 17 inches long, the mother-cells and sperm-cells were found , the latter numerous and lively, from 1/3000 to 1/20000 inch in diameter. The eggs were white, just large enough to be distinguished by the naked eye, measuring a little less than 1/2 mm.
Why are eels so weird?
Even if you cast out the infamous electric eel, the fish are incredibly odd because no one knows where they come from These sea creatures lack reproductive organs of any kind. Their lack of obvious reproductive organs has enshrouded eels for thousands of years.
Do eels lay eggs?
As catadromous fish, European eels spend most of their adult lives in freshwater rivers, streams, and estuaries before returning to the open ocean to spawn and lay eggs As young larvae, baby eels drift around the sea for between seven months and three years.
What is the eel question?
Where did they come from? “The eel question” is one humans have been attempting to answer for millenia Mount says that the best scientists can tell, all American and European Eels are born in the
sargasso sea
, northeast of Bermuda. The closer you get to the Sargasso, the smaller the eel larvae become.
Are eels asexual?
Freshwater eels spawn in the Sargasso Sea after migrating thousands of miles from freshwater streams and rivers. Researchers believe they spawn via external fertilization The females release millions of eggs into the water where they are fertilized by the male’s sperm.
How do electric eels not shock themselves?
They reduce the danger to themselves by flexing their bodies in a shape that prevents the electric current from passing through their heart When they are charging up, they stiffen into a line segment very much like a straightedge. This way, the electric current only runs parallel to their tail and behind the heart.
Are moray eels asexual?
Reproduction of Moray Eels Moray eels reproduce by fertilization that is oviparous , when eggs and sperm are fertilized in the water outside the womb, also known as spawning.
Do eels have genders?
When identifying whether eels are males or females, the key feature to look for is whether the gonad has a distinct lobed or scalloped appearance, a little like a row of beads – if it does, the eel is male If the gonad or is more like a ribbon of tissue of the same width, resembling a net curtain, the eel is female.
Are all eels born in the Sargasso Sea?
( Both American and European eels are born in the Sargasso Sea , but it is still unclear how their respective larvae know which way to go). As eels begin to reach the shores of their destination, they morph into a form known as a ‘glass eel. ‘ The eels are still transparent, just slightly larger.
Do eels have electricity?
Electric eels have three sets of internal organs that produce electricity The organs are made up of
special cells
called “electrocytes.” Electric eels can create both low and high voltage charges with their electrocytes. Electric eels generate their electric shocks much like a battery.
What are glass eels?
Glass eels typically refers to an intermediary stage in the eel’s complex life history between the leptocephalus stage and the juvenile (elver) stage Glass eels are defined as “all developmental stages from completion of leptocephalus metamorphosis until full pigmentation”.
What are baby eels?
Baby (larval) eels are flat and transparent (clear) They are called leptocephalus (Greek for “thin head”). A young eel is called an elver.
Do scientists know how eels reproduce?
It is mostly true that scientists don’t know the full reproductive cycle of eels in the wild The caveat is that, contrary to claims made on social media, they have been observed reproducing in captivity and their sexual organs have also been observed.
What does eel taste like?
Some people claim eels taste bland, but it is not. It combines the sweetness and soft yet fairly-firm texture, creating the delightfulness of eel meat. Somehow it tastes like raw salmon, squid, or lobster They also have a high level of oiliness.
How old can eels get?
They can also live for many years. Large longfins have been estimated to be at least 60 years old The biggest eels are usually old females that have been slow to reach sexual maturity and, for reasons that are not yet understood, have not migrated to sea to breed.
Why do eels have electricity?
Electric eels – actually a type of knifefish, not true eels – are notorious for being able to produce a hefty electric shock of up to around 600V. The source of their power is a battery-like array of cells known as electrocytes , which make up around 80 per cent of the eel’s metre-long body.
Why are eels called electric?
These famous freshwater predators get their name from the enormous electrical charge they can generate to stun prey and dissuade predators Their bodies contain electric organs with about 6,000 specialized cells called electrocytes that store power like tiny batteries.
What were electric eels before electricity?
When the species now defined as Electrophorus electricus was originally described by Carl Linnaeus in 1766, he used the name Gymnotus electricus , placing it in the same genus as Gymnotus carapo (banded knifefish) which he had described several years earlier.
What are eels eaten by?
- Herons.
- Eels.
- Raccoons.
- Storks.
- Eagles.
- Osprey.
- Sea snakes.
- Barracuda.
Do eels have poisonous blood?
Eel blood is poisonous to humans and other mammals , but both cooking and the digestive process destroy the toxic protein. The toxin derived from eel blood serum was used by Charles Richet in his Nobel Prize-winning research, in which Richer discovered anaphylaxis by injecting it into dogs and observing the effect.
Can eel be farmed?
Eels are an ideal species of fish to be farmed because they are very tolerant of many conditions, including being kept in large numbers. After the fingerlings have been in quarantine, they can then be grown-on in ponds or in specialised tanks that recirculate the water.
Are wolf eels real?
Wolf eels aren’t eels at all—they’re fish, and not the same as true eels One key distinction is that wolf eels have pectoral fins behind their heads, which is characteristic of fish, not marine eels like morays. Put simply, they’re a just a long, skinny fish!.
Can you eat eels?
The meat of the eel has a distinctive and beautifully clean flavour. And eels make easy eating, because they have just one bone running down the middle, so they’re not finicky things On the preparation side, most recipes call for the creature to be skinned.
Do eels bite?
“ Eel attacks are quite rare Basically, eels aren’t aggressive to humans,” he said. “If they feel trapped or if a human sticks their foot down in a hole, they may defensively bite.”.
What does eel mean in physics?
collision energy of electrons surface analysis technique known as electron energy loss spectroscopy (EELS) that measures the energy lost when low-energy electrons (typically 5–10 electron volts) collide with a surface.
What is another word for eel?
•Other relevant words: (noun) soft-finned fish , malacopterygian, pitty, fish.
Are eels halal?
Hanafi. In the Hanafi school of Sunni Muslim jurisprudence, to which the majority population of Sunni Muslims belong to, only “fish” (as opposed to all “sea game”) are permissible, including eel and hagfish.
Are electric eels AC or DC?
The electric eel, however, emits not a direct current but an alternating current (in pulses), and its charge is depleted after a strong shock.
How did electric eels evolve?
ELECTRIC EELS AND THEIR SUPERCHARGED MUSCLES Between 100 and 200 million years ago, some fish began to amplify that potential. They evolved electrocytes from muscle cells , which were organised in sequence and capable of generating much higher voltages than those used to make muscles work.
What animal eats electric eels?
What eats electric eels? Apart from being fished by humans, electric eels have no known predators They are too dangerous for other species to go after, regardless of water levels. If the water is shallow, there’s a chance that large land mammals will go after them, but this threat is often deterred with a shock.
Citations
https://www.sciencetimes.com/articles/27172/20200904/why-aristotle-freud-many-others-fascinated-european-eels.htm