The Truth About Hippocamps

There’s something just as mythical as a heffalump that has an equally cool name: the hippocamp. It’s a creature from Greek mythology that looks like a horse on top. But its lower body and tail are more fish-like and it lives in the water. The hippocamp is also not to be confused with a Hippopotamus (a.k.a. Hippo), which also has a cool Greek-derived name, but looks more like a barrel than a fish (and not much like a horse either).

Trevi fountain

If you’ve ever seen the Trevi fountain in Rome or admired pictures of it, you’ve seen hippocamps. Without a close look, you probably thought they were horses. In art and sculpture, horses are on the good side most of the time, but here these animals are not pulling Oceanus’ chariot. These horses have wings; no, they are fins, which makes them hippocamps. And they are fighting with the Tritons, male mermaids who are pulling the chariot of Oceanus.

So the theme “Taming of the Waters” for which the Trevi fountain is known, actually could be “Taming the hippocamps.”

Seahorses

In English, the mythical hippocamp is often called a “seahorse.” And that same name is applied to 45 species of fish in the genus Hippocampus. With arch shaped necks and delicate snouts, seahorses have a horse like appearance that endears them to humans. And being an aquatic species, maybe they are the closest thing to a hippocamp that really exists.

Seahorses are a far cry from the raging horse demons in the Trevi fountain, however, and wouldn’t stand much of a chance if a hippopotamus jumps in a river either.

Hippocampus of the Brain

The term hippocampus also is used for a component of the brain. It sits below the cerebral cortex. This section, when removed, looks much like a seahorse, as you can see from the picture here.

The hippocampus and a seahorse. Creative Commons via Wikipedia.com by Prof. Laszlo Seress.

The hippocampus deals with memory. Specifically, it is associated with the consolidation of short term memory into long term memory. It allows us to distinguish between past and present. Trauma-related experiences get locked there. And in Alzheimer’s patients or with other dementia, it’s one of the first places that shows evidence of damage.

Neptune’s Smallest Moon

And that brings us to Neptune’s smallest moon, which also was given the name Hippocamp by its discoverers, Mark Showalter and other astronomers at the SETI Institute. This week, a new analysis was published of the nature of this moon. It tells us that the moon is around 21 miles (34 km) in diameter.

Image of Neptune's inner moons from NASA via Space.com article linked below.

The small moon orbits very close to Proteus, which is more than 10 times its size. Like earth’s moon, Proteus has been moving slowly away from its planet, so in the past it would have been in the same place as Hippocamp is now. Astronomers say this means that Hippocamp is younger and may be a small piece of Proteus, perhaps dislodged from the impact of a comet.

Why was Neptune’s moon Hippocamp given that name?

"So, officially, it's named after this mythological creature," astronomer Showalter told Space.com. "But partly, in my mind, it's named after seahorses, because I think they're cool."

And now you know the whole truth about hippocamps.

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References:

https://www.nationalgeographic.com/science/2019/02/meet-hippocamp-newest-known-moon-neptune-hubble-space/
https://en.wikipedia.org/wiki/Hippocampus_(mythology)
https://en.wikipedia.org/wiki/Trevi_Fountain
https://en.wikipedia.org/wiki/Hippopotamus
https://en.wikipedia.org/wiki/Seahorse
https://en.wikipedia.org/wiki/Hippocampus
https://www.space.com/neptune-smallest-moon-hippocamp-named.html

Images public domain except for those otherwise credited in the text.