Pinnipedia and Sirenia Musings

I've been so busy and have too many things to want to put up here, but can't seem to make the time in the evening lately. Life is just like that sometimes.

Anyway, I have this post for right now, a post that would have felt right at home in 2009 back when I would have done this exact thing: inexplicably describe a tiny corner of this world's biosphere and the connections that were until then unknown to me.

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In my imagination, I tended to rank the walrus as the largest pinniped, the marine mammal clade that hosts seals, sea lions, and walruses. The tusks on the walrus can max out at one meter, and seeing as how natural (see "not excessively huge") they looked in pictures led to this conclusion.

Was it true? Are walruses the largest pinnipeds?

At our aquarium here in Long Beach, the Aquarium of the Pacific, they have a very cool pinnipedia area with three harbor seals (one is a year old pup!) and three sea lions, which dwarf the seals. The largest is the massive Parker, an old bull sea lion that's older than he'd be able to live in the wild. Here he is:

He doesn't look that massive in this picture, but he'll be hitting 800 pounds by this summer, which is, eh, good-sized.

Certainly smaller than a walrus, right?

So, then one day we were watching an episode of Blue Planet II and they were showing the bull elephant seals fighting on the beach:

These mountains of critter bashing each other to bloody messes got me thinking: how could a walrus be bigger than one of these things? I mean, seriously:

And that's a smaller female...

So, I did what I used to do all the time when I had the late-night time: crawled down the rabbit hole.

It turns out both northern elephant seals and southern elephant seals are larger on average than walruses. I ended up finding this comparative poster from an aquarium or museum:

This then got me thinking about dugongs and manatees.

When it comes to aquatic and marine mammals, besides the water-weasels---otters---we've got cetaceans, aka the whales, broken up into the mysteceti (baleen whales) and odontoceti (toothed whales); the pinnipeds, seals and sea lions; and the vegetarian dugong and manatee, whatever they were.

I thought they were closely connected to each other, but knew that they weren't whales or water-bear-pinnipeds. This was part of the rabbit hole dive. I remember hearing that they were closer to elephants than to anything else. The dugong looked pretty freaking big in a different episode of Blue Planet. How did it size up to the manatees? And the largest pinnipeds?

Manatees and dugongs are in the clade Sirenia, so called because they were mistaken for, eh, shapely mermaids or sirens. Sirenia is in the lineage that had a rather recent common ancestor with elephants and hyraxes.

I found this comparative poster for them as well:

Manatees are more massive than dugongs on average, and are larger than many pinnipeds as well. Both are far closer in day-today behavior to cattle than the fish-and-penguin hunting pinnipeds, so those plump and doughy looking bodies are in fact plump and doughy. Those massive and surly elephant seals may look round and blubberous, they, in fact, could chase you or me down on the sand, having that inch-worm like locomotion called galumphing.

It was always a strange imagination I use to have, being chased down the beach by a gigantic seal. They used to beach themselves in Cambria, close by to Cal Poly, and we'd take trips to look at them. One of the bulls I remember thinking was at least as big as my Datsun 240-Z.

I think as a kid I preferred sea lions, but mostly because they're closer in appearance to dogs than the galumphing seals. Elephant seals, though, don't eff around. So I don't know where I am with that...(like it matters).

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I have a few more posts like this, random old school stuff that I've been working over in my head for a while...