Is the Loch Ness Monster Really a Marine Reptile?

Is Nessie a Plesiosaur? Science Weighs the Evidence

Sepia photograph showing a rendering of the Loch Ness monster.

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Ever since the Loch Ness Monster was "discovered" in 1933, one popular theory has been that this lake-dwelling creature is a plesiosaur--a type of marine reptile that was supposed to have gone extinct 65 million years ago, at the end of the Cretaceous period. This is an easy claim for so-called cryptozoologitsto make, and a very difficult one to prove--and the weight of the evidence is that, if the Loch Ness Monster truly exists (and that's a very big "if"), the odds are extremely slim that it could be a plesiosaur. (See 10 Facts About the Loch Ness Monster)

First Things First - Is the Loch Ness Monster Real?

Before we get to the issue of what type of animal the Loch Ness Monster might be, we first have to explore the issue of whether or not the Loch Ness Monster really exists. The first "sighting" of this presumed lake dweller occurred in 1933 (perhaps, not so coincidentally, the year the movie "King Kong" was released) by a local Scottish journalist who related the experience of one of his neighbors: "the nearest approach to a dragon or pre-historic animal that I have ever seen in my life," the man is quoted, further elaborating that it carried what looked like a newly killed animal in its mouth.

Here, in a prehistoric nutshell, is pretty much every Loch Ness story down to the present day. Most Nessie sightings have been reported second-hand, in accounts along the lines of "You're asking me if the Loch Ness Monster real? Well, my friend's dentist's sister was walking by the lake one day when she saw..." In this respect, the Loch Ness Monster has a lot in common with other cryptic creatures like Bigfoot or Mokele-Mbembe: practically all the evidence for its existence is based on hearsay or rumor, with very little in the way of hard fact.

Of course, it doesn't help that most (if not all) of the physical evidence attesting to the Loch Ness Monster has been faked. The most famous "photograph" of Nessie was published in 1934, and conclusively identified as a fraud over 40 years later. In a 1999 book, one of the participants in the hoax admitted that this convincing-looking "monster" was actually a toy submarine with a sculpted head glued to one end (which, naturally, hasn't deterred some true believers from insisting the photograph is real). Another, more recent "photograph" shows only a hump in the water, which could be anything from a dead turtle to a submerged Volkswagen.

Could the Loch Ness Monster Be a Plesiosaur?

If, despite all the evidence presented above, you persist in believing in the Loch Ness Monster, you'd probably like to know what kind of animal it is. Very early on, the "Nessie-as-plesiosaur" theory was the leading contender, partly because of that faked 1934 snapshot, and partly because plesiosaurs (and other marine reptiles) were very familiar to the English and Scottish public; some of the first fossils of the breed were discovered along the English coast in the early 18th century, by Mary Anning, the woman who inspired the ditty "she sells sea shells by the sea shore."

However, there are a few major problems with identifying the Loch Ness Monster as a plesiosaur. Here are five of them, in no particular order:

--Plesiosaurs were equipped with lungs, and needed to surface on a regular basis to breathe air. With all of the eyes trained on Loch Ness over the last 80 years, you'd think this habit would have drawn some attention!

--As ancient as it may look to the uninformed, Loch Ness is only about 10,000 years old, and was frozen solid for about 20,000 years before that. The last plesiosaurs went extinct 65 million years ago, along with the dinosaurs.

--Plesiosaurs (and other marine reptiles) were cold-blooded animals that needed to swim in temperate waters. The average temperature in Loch Ness is about 40 degrees Fahrenheit; it's not exactly a Caribbean paradise!

--Based on its "description," Nessie would be a mid-sized plesiosaur, weighing one or two tons. There simply wouldn't be enough food in the tiny Loch Ness ecosystem to support the needs of such an enormous beast.

--There's absolutely no evidence that plesiosaurs held their necks out of the water, the way Nessie is depicted in that fake photograph. That may be the appropriate posture for a swan, but not for a fierce marine reptile that feasted on fish and squids!

If the Loch Ness Monster Isn't a Marine Reptile, What Is it?

If we weigh all the available evidence about the Loch Ness Monster, the most logical conclusion is that it simply doesn't exist (of course, tourists bring in a lot of money, so it's in the interest of Scottish locals to perpetuate the myth). And even if you insist that the Loch Ness Monster is real, you can't reasonably make the case that it's a plesiosaur. What are the other options? Well, Nessie (at least when it was first sighted) could have been a seal, or it could have been an amphibian, or it could even have been an elephant that wandered away from a nearby circus. But no, sad to say, it was not a living, breathing relative of Elasmosaurus.