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Otaries

otaries

It’s funny how some words fall out of use when they actually do have some great clarifying utility.

One of the hardest concepts to understand is that the creatures we call “fur seals” and “sea lions” aren’t actually “seals” in the same way we understand harbor or gray seals.

In modern English, these animals get called “eared seals,” which is confusing term in itself. The other seals do have ears, of course, but only fur seals and sea lions have external ear flaps. The eared seals can also pull their hind flippers under their bodies and walk, while the “earless” seals are forced to drag their bellies around on ground with their front flippers.

We currently classify the earless seals as “phocids” (easy to remember if you know the French word for seal is phoque). The eared seals are called “otariids,” which is easy to remember if you think that otters have ears and these are the seals that are most like otters.

But I have wondered where this word came from. Obviously phocid came from Latin by way of the Ancient Greek word “phōke.”  I don’t see much use in using this word in English, though in the Romance languages, some variant of this word is the actual word for seal.

The name for the eared seals is otariid. If you know your Greek, ōtos means ear, and ōtaros means “large-eared.” Because these animals have external ear flaps. they have larger ears, which is also another way to remember the two groups

The French use the word “otarie” for these animals, and as I was going through some of the nineteenth century naturalist accounts of these seals, I noticed that an Anglicized word “otary” was used for them.

The term has since fallen into disuse, but it might be necessary to revive it. A fur seal or a sea lion really isn’t the same thing as a seal in my mind. They swim and move so differently that they really aren’t in the same ball park. To me, a seal will always be an animal made up of blubber into a sausage that can barely move on land, while an otary is an animal that can run and swim.

Using otary for these animals divides them better cognitively from the seals.

But then I don’t think most people would lose sleep over calling a sea lion a seal, even if it’s not really a seal.

The English language first evolved in a place where there are no otaries, but when these animals were noticed by English-speakers, there was attempt to classify them as being like the gray and harbor seals that they knew so well.

But I think this leads to a confusion of two quite different families.

Maybe this is me being a nerd.

But I think it’s time to use the term “otary” in our common language.

 

 

 

 

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From the BBC’s Planet Earth series:

Source.

This is pretty famous footage, but I noticed in the sequence something that is worth exploring from evolutionary perspective.

Notice that when the fur seal catches the penguin, it uses a vigorous shaking motion to complete the dispatch.

It doesn’t kill the penguin quickly. In fact, the seal had tried to rip out its throat, that would be a much quicker way to kill the prey.

However, its very likely that the seal cannot make a choice as to the best way to kill the penguin.

Its killing motor pattern is likely inherited, and anyone who has a dog can recognize the sequence. Give a dog a toy to play with, and they very often exhibit a vigorous shaking pattern as they play with the object.

It’s a motor pattern that has to be trained out of most retrievers, but as a type, they tend to exhibit this motor pattern less often than other dogs, though there is quite a bit of variation within individuals.

In my short time with Pavel, the West Siberian laika, I noticed that his shaking motor pattern was quite vigorous compared to Miley’s. That’s because Pavel’s ancestors have never really been expected to bring prey to hand alive, while Miley’s certainly were. Indeed, Pavel’s ancestors had to kill sable and other fur-bearers and fight off bears and wolverines. Miley’s most immediate ancestors came from genteel shooting estates from Great Britain, where the biggest predatory mammal is the Eurasian badger.

This motor pattern is instinctive in dogs. It does serve a purpose whenever one sees a dog catch a smaller mammal or a bird. A few vigorous shakes usually breaks the neck of the quarry, and it then can be eaten.

This same motor pattern also exists in bears, and when one reads of a grizzly bear attack, the victims often experience violent shaking in the bear’s jaws.

Because this behavior exists in dogs and bears, one can see why the Antarctic fur seals engage in it.

Within Carnivora, there are two major suborders– Feliformia and Caniformia. Bears, dogs, and seals (including true seals, the walrus, and the fur seal and seal lion family) form a clade.

That means they all share a common ancestor about 40 million years ago.

At that time, the dog and bear lineages diverged.

And then about 23 million years ago, the bear and seal, sea lion and fur seal, and walrus lineages diverged. Bears as we know them now didn’t evolve until about 20 million years ago, and the ancestor of the seals and other marine Carnivorans was actually something like an otter.

Fur seals are actually sea lion species, and Antarctic fur seals live almost exclusively on krill. They’ve likely been living on krill for thousands of years, and their ancestors have been living a marine existence for millions of years.

If this shaking motor pattern in Antarctic fur seals is inherited, as I think it likely is, then dog breeders who want to breed it out might have a task on their hands.

For thousands and thousands of generations, these seals have not needed this shaking behavior in order to survive, but when they engage in something similar to the predation of their terrestrial ancestors, they engage it.

I would like to see some comparative studies of this shaking  motor pattern in different fur seal and sea lion population in order to see if this behavior actually is inherited.

But if it is, it is a wonderful example of an historical legacy.

A wonderful little piece of evidence for evolution.

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