An Electrogenic Mammal?
Posted by: Loren Coleman on August 5th, 2007
There are three known kinds of electric – more correctly called electrogenic – animals:
(1) the one species, Electrophorus electricus, of South American electric eel (really a knifefish),
(2) the 19 species of African electric catfish in the genera Malapterurus and Paradoxoglanis, and
(3) the 69 species of electric rays (order Torpediniformes) found around the world.
The first two fish both demonstrate the ability to shock prey with electricity as an effective strategy for a piscivore (an animal that eats fish). They produce high levels of voltage, e.g. electric eel (600 volts) and the electric catfish (350 volts). Electric rays can produce an electric discharge used to stun or kill prey, from as little as 8 volts to up to 220 volts depending on the species.
Could there be an electrogenic mammal?
The range of Potamogale velox (pictured at the top) is limited to western central Africa, where this story opens.
I recently received news from a zoologist detailing just such a possibility:
I have spent a lot time in Central Africa collecting. I have repeatedly heard stories from locals in Gabon about a cat-sized mammal that gets caught in fisherman’s gill nets that delivers a powerful electric shock…one worse, reportedly than that given by the common electric catfish.
Initially I was puzzled about the identity of the mammal they were talking about, but at some point realized it had to be Potamogale velox, the giant otter “shrew” (actually a tenrec) which is common in this area. I have pulled drowned individuals from my traps on two occasions, but have not examined them for an electric organ. Next time I get the chance, I will.
Potamogale velox is called the “giant otter shrew” but it is not technically a shrew. Shrews belong to family Soricidae while Potamogale velox is a tenrec (Family Tenrecidae). Both families were once placed into the mammal order Insectivora, but Insectivora allegedly is no longer recognized as a natural group.
Of course, a live one would be more interesting. Apparently they die quickly in captivity. I thought I’d pass this along to you in case you [or your readers] have heard other similar accounts.
There are no known electrogenic mammals, i.e. mammals which have electric organs that produce electric discharges. The platypus may be the only mammal that has an electrosensory system and can perceive the weak bioelectric field that surrounds its prey. If (and it is a big IF) the giant otter shrew is electrogenic, it would be a first and would be a zoological discovery of huge proportions.
I’ve heard the electrogenic mammal story on at least three occasions at three different [central African] localities, usually after a brief discussion or encounter with an electric catfish. “Oh, that is nothing,” they will say, “compared to getting a shock from a [not understood, unfamiliar name for the creature].”
One place I remember hearing this story very clearly is on the shore of Lac Zilé near Lambaréné in Gabon.
Maybe someone else will see this and chime in with more info. If someone who is interested in sponsoring a trip to Gabon to collect this beast, feel free to refer them to me.Zoologist, name on file, who works in a sensitive employment location where talk of cryptids would perhaps not be appreciated.
It looks like there’s a new cryptid to add to all our lists.
Is Potamogale velox the answer to this new mystery or is it a new species?
About Loren Coleman
Loren Coleman is one of the world’s leading cryptozoologists, some say “the” leading living cryptozoologist. Certainly, he is acknowledged as the current living American researcher and writer who has most popularized cryptozoology in the late 20th and early 21st centuries.
Starting his fieldwork and investigations in 1960, after traveling and trekking extensively in pursuit of cryptozoological mysteries, Coleman began writing to share his experiences in 1969. An honorary member of Ivan T. Sanderson’s Society for the Investigation of the Unexplained in the 1970s, Coleman has been bestowed with similar honorary memberships of the North Idaho College Cryptozoology Club in 1983, and in subsequent years, that of the British Columbia Scientific Cryptozoology Club, CryptoSafari International, and other international organizations. He was also a Life Member and Benefactor of the International Society of Cryptozoology (now-defunct).
Loren Coleman’s daily blog, as a member of the Cryptomundo Team, served as an ongoing avenue of communication for the ever-growing body of cryptozoo news from 2005 through 2013. He returned as an infrequent contributor beginning Halloween week of 2015.
Coleman is the founder in 2003, and current director of the International Cryptozoology Museum in Portland, Maine.
Just to nitpick, there are also other types of electric fish (generally very small) in the Amazon system.
There’s no obvious reason why there could not be an electrogenic mammal – it’s a useful capability if you are semi-aquatic like P. velox is. It’s a big leap in evolutionary terms, though, because you need a whole new organ with no obvious progenitor. If you’re delivering the kind of heavy-duty shocks described in the account, it has to be a large organ. thus easy to find, and it can’t have escaped notice in a known species for which a holotype has been collected and specimens presumably stuffed and/or dissected. Moreover, since the species has been kept in captivity (even though it does not survive long), it is difficult to believe no one handling a captive one has reported a shock or noticed anything really odd about the animal’s anatomy.
So if the accounts of a shock from a mammal are true, an unknown species which superficially resembes P. velox is more likely.
Electrogenic abilities would make sense for this shrew, which doesn’t look as though it would very adept at out-swimming their prey. Shrews are some of the most primitive mammals on earth, so they’ve had a lot of time to evolve this specialty. I’ve read that many electrogenic animals live in muddy waters, with low or no ability to see their prey. I wonder if this is true in Gabon, where these animals live.
Of course, catching a live specimen will be the only way to find out. Just be careful to wear rubber gloves!
Very interesting. Thanks for the article.
Now I know what the hamsters are charging up when they’re running on their wheels…
I thought platapus released electric pulses too?
Interesting article, this possibility of an electrogenic mammal never even crossed my mind! But it would be awesome if it turned out to be true!
Very cool.
Very interesting. Has anyone of the people reporting this said where the shock originates from (ie: whiskers, mouth or something hidden and not usually seen by cameras)? I guess I’m a little different from most, nothing like this surprises me–excites me, yes, surprises, no. I have long ago set aside any social preconceptions about what animals can do. I say social because we are taught what we think all animals can do, therefore it is our society that sets up the main stream ideas of what animals are out there and what they are suppose to be able to do. That’s why we are here, to find the facts about what is known and unknown.
The platypus senses electrical impulses of moving creatures through it’s bill, it’s how it hunts for food. They don’t generate an electric shock though. The male platypus does have a poisonous spur on its hind foot, thus making it one of the few poisonous mammals.
But at some point realized it had to be Potamogale velox, the giant otter “shrew”.
I was gonna say it looks like an Otter Rat to me. Or a Rat Otter.
Come to think about it, is a platypus even a mammal? It lays eggs.
Yes, the platypus is a mammal.
Matt – it might be possible to have a holotype in a collection and not realise that a species is electrogenic. For example, if only one sex were collected, and it is the other which has the electric organ. If I recall correctly, this may have been the case for an alleged light-producing lizard – we don’t know as we have not yet collected both sexes.
Case in point – the platypus – only the males have the spurs.
Darkshines – as Ceroill says – platypuses are mammals (as you say, that lay eggs). Other mammals include the marsupials which give birth to bean-sized young that make their way to the marsupium (pouch) where they continue their development until independence (eg kangaroo), and those which give birth to fairly fully-formed young (eg humans).
Did you know that the South American knife and elephant fishes which produce electric pulses are used in water treatment plants? By measuring the electrical activity in the water generated by these fish, scientists can determine the amount of chemical pollutants present. They form a sort of last safety check before the water is declared safe. In the wild these fishes use their electrogenic ability for communication. Although Matt mentioned these are small fish, together they comprise over 300 species.
The Australian deep-sea stargazer is also an electrogenic fish producing about 20 volts.
Interesting story. I am not so familiar with this species of shrew, so I don’t know how often it is actually encountered by humans, but if it is encountered often, I would think it would be more common to hear of its electrogenic properties. It would be helpful to know exactly how often these types of reports of a mammal shocking people is above and beyond the smattering of stories this zoologist personally heard about. I’d also like to have more credible evidence that the assumption he made that it “must” be the giant otter “shrew” is correct. Did he show any of the specimens he had to the natives to verify if in fact this was the animal they mentioned? Perhaps it is an unknown animal and this person just made the conclusion that Potamogale velox must be what they are talking about without any corroboration, in which case building a case on this species being electrogenic is arbitrary and speculative.
I won’t discount the possibility of an electrogenic mammal, but I’m trying to look at other possible explanations first here before jumping to a completely unknown type of mammal. I wonder if there is a possibility that this animal they speak of is also a piscivore and preys on the same species as other electrogenic fish in the area, in which case there would be a chance that fisherman would capture them together. This seems reasonably possible since the reports that were given involved fishermen who caught them in their nets. If this were true and the mammal in question was captured with an electrogenic species, then perhaps it was in fact the fish that shocked the fishermen and somehow the “shrew” was mistakenly blamed as the culprit. Word of mouth and tall tales could easily exaggerate the level of electric shock given and before you know it, there is an alleged electrogenic mammal running around. I’m not saying this is the case, but it is as good a possibility as any given the facts we have to go on.
I definitely would be excited by a find of this type, though, and hopefully there will be a specimen to examine that will shed light on the phenomena.
As noted, it is not a shrew but a tenrec.
Also, as mentioned, it is assumed the locals are talking about a known animal with a electrogenic organ used to kill fish to eat them. But by technical definition, this animal would be a cryptid, an unknown animal, until it is identified positively.
Furthermore, in the beginning of any cryptozoological investigation, the usual understanding is that the “new animal” will be made fantastic or at least it’s behavior, size, and attributes might be made to be larger than life.
BTW, my informant reports there was a very clear division between the electrogenic behavior of this cryptid mammal and that said to be caused by the local electric catfish.
I see, Loren. I put quotes around the word in a similar manner to the one who reported this when using “shrew” to denote that I knew it was not in fact a shrew. I should have just said tenrec to avoid confusion.
What you said about an unknown animal’s attributes being made somewhat larger than life is exactly what I was getting at when speculating about whether this was perhaps an electric catfish shock mistakenly attributed to a known or unknown mammal. The source says the delineation is clear between the behavior of the two, but if there is the understanding that attributes can be over exaggerated, then I wonder if an electric catfish shock might not have been overblown as well. If this were the case, with the shock exaggerated and attributed to another animal, then it seems to me that the behavior of this proposed electrogenic mammal would be the result of making the mundane more fantastic than it perhaps really is.
Then again, I suppose it is stretching a bit for me to think that experienced fishermen could make a mistake like that with animals they are no doubt familiar with. Ah well, I just like speculating on these things.
I am the source of this story for Loren and I thought I would respond to some of the comments and questions. Many of the comments are very astute. Let me first of all say that I myself remain skeptical about these stories. It is possible, as mystery man suggests, that this is folklore that has grown out of confusing a shock delivered from an electric catfish with the presence of a trapped P. velox, both of which must occasionally be caught together in fishermen’s nets. It is the fact that I have heard this story three times at three different localities in Central Africa and each time the information was unsolicited from me (they weren’t trying to please me by telling me something I wanted to hear) that makes me consider the possibility that there could be something to it.
As MatteBille points out, it does seem unlikely that a biologist at some time has not handled a P. velox and experienced a shock if it is indeed capable of delivering one and that no one has ever observed what must be a large electric organ upon dissection. I am trying to locate mammalogists who have worked on tenrecs in Africa to ask them these very questions. It is possible that no one has ever had observed a live P. velox in captivity and also possible that no one has looked for an electric organ upon skinning one. IMO, the only place for an electric organ in P. velox would be in its muscular tail. Examination of the tail musculature in a dead P. velox would surely reveal unusual anatomy if it contained an electric organ, but it is not inconceivable that it could have escaped the notice of those who have prepared museum skins.
As I say, I will report back when I learn more.
Just curious here, but what, exactly, would an electrogenic organ look like? It was always my understanding that the electric eels generated the charge from pits in their skin…of course now that I think about it, those may instead be for detecting electrical signals.
Also, the Stargazer species along the Atlantic Coast generate a shock from their heads, not just the ones from Australia.
Is it possible that this mammal can only deliver a current when wet? That might explain why no one has been shocked by an animal in captivity!
The photo suggests the skin and fur on the tail are different from the body, with fur nearly absent. Is this correct? This is somewhat suggestive of an electric organ, just as monotremes (platypus etc.) have no fur on their electric sense organs.
I believe it remains unsettled whether the star-nosed mole uses the star for electroreception: one paper reported somewhat weak but supportive behavioral evidence, and another doubted this on the basis of detailed micro-morphology, which did not resemble that of other known electroreceptors, but was unusual.