Stories of Origins and Evolution

Science, traditional ecological knowledge, and personal experience all give valuable insights into the stories of seals and their origins.

Traditional Ecological Knowledge

Sedna, her fingers becoming seals, whales, and porpoises. Her hair tangled as kelp. (Image: Germaine Arnaktauyok, Canadian Museum of History.)

Indigenous cultures across the Arctic trace the origins of sea mammals to ᓴᓐᓇ (Sedna, or Arnakuagsak), the Inuit goddess of the sea and marine animals. There are many stories of how Sedna created the beings of the sea. One, as described by the Inuit Art Foundation in referencing contemporary artists’ works, says Sedna’s ”fingers were cut off as she clung to the side of her father’s kayak and eventually became the creatures of the sea.”

Drawing of seal and traditional wampanoag design.

Art by Elizabeth James-Perry

Mashop & Squant

The Wampanoag worldview, as expressed through the Mashop and Squant transformation stories, describes a fluid relationship between humans and the rest of creation. Clan identity among tribal nations expresses kinship of humans and animals; many Wampanoag clans are drawn from ocean beings.

Selkies

Norse and Celtic people tell of Selkies who shift between human and seal form (as shown in this postage stamp from the Faroe Islands), another way of expressing the close tie between land and sea that pinnipeds share. Well into the 20th century, Irish people who lived alongside, hunted for, and observed seals shared stories of selkies as part of their daily lives.

(Image: Edward Fuglo, Postverk Foroya)

Biological Science

There are 34 species of pinnipeds in the oceans of the world today. Some, like the crabeater seal and the harp seal, number in the millions. Some, like the Hawaiian monk seal, teeter on the verge of extinction. In evolutionary history, there are more than 50 extinct species, and scientists are continuing to make new discoveries in the fossil record.  

If you look at the worldwide distribution of pinnipeds today, they are in every ocean of the globe, from the Arctic to the Antarctic. In the Indian Ocean, there are not currently any resident pinniped populations, but Southern Ocean species will wander through those waters. 

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Arctic Evolutionary Origins

The evolutionary story of seals, sea lions, and walruses (the pinnipeds) takes us back into deep time and north, where the story begins around 25 million years ago.  

Since pinnipeds were “named” by German naturalist Johann Karl Wilhelm Illiger in 1811, people have debated the relationships of pinnipeds to each other and to other mammals.  

Were they all descended from a common ancestor? Were the eared seals more closely related to bears, the true seals more closely related to weasles?  

The proto-seal, researchers agree, was a carnivore living in the Arctic.  Maybe an early weasel species, maybe an early bear species.  Whether mustelid or ursid, this small mammal moved between land and shore, largely in fresh water.  But for many years, the “missing link”  that showed the movement into a largely marine environment, in which the mammals would spend most of their lives at sea and only periodically touch upon land, was missing.

Some clarity has emerged since the 1990s, as both researchers studying the bones and the genetics of pinnipeds came to agree that one ancestor is common to all pinniped.  But when and where did that ancestor live?

Image: Nobu Tamura (http://spinops.blogspot.com)

Image: Nobu Tamura (http://spinops.blogspot.com)

This drawing represents what scientists THINK the ancestor of modern seals looked like. Read on for more…..

Re-articulation of the ancient, proto-seal. (Image: Kevin Guertin, Ottawa, Canada)

Finding the Missing Link

In 2007, Natalia Rybczynski a paleontologist with the Canadian Museum of Nature, was working with a team on Devon Island in the Eastern Canadian Arctic.

She was waiting for a fuel delivery and, as she scanned the area, she kicked some dirt and discovered a bit of bone. Curious, she looked more closely. It turned out she had discovered a fossil which was eventually recognized to be from an ancient, before-undocumented early pinniped.

Researchers named the new, ancient species Puijila darwini.  “Puijila” is an Inuktitut word meaning "young sea mammal,” and the name was determined in conjunction with the government of Nunavut, within which Devon Island lies. 

This new fossil, many think, is the “missing link” between land and sea that scientists had been looking for.  Puijila looked a bit like a contemporary otter, with a long tail and legs that were built for both walking and swimming, and they lived 23 million years ago. 

At the time Puijila lived, Devon Island’s climate would have been quite warmer.  But the earth was headed for a few ice ages, and over the next million-plus years, the pinnipeds we know today evolved. This was also the age in which the apes appeared, and many mammals, birds, and plants from that time might look familiar today.

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And Then What?

How did the radiation of pinnipeds from the Arctic unfold? It took millions of years for seals, sea lions, and walrus to develop into their contemporary species.

It looks like the “eared seals” (Otariids) evolved in the North Pacific 11 million years ago and distributed southward from there. There are 15 species today, all in the Pacific.

The true seals?  There are 19 species of phocids today, and they thrive in many oceans.

A fossil from South Carolina dated to the late Oligocene (29 – 23 million years ago) may be the oldest known.  

Walrus, the strangest and most mysterious of all the pinnipeds, developed last (maybe?). First, these toothy pinnipeds (minus tusks at the time!) were only in the North Pacific, though today walrus are found in both the north Pacific and Atlantic.  Scientists are still in debate about the specifics of walrus evolution. There are fossil records of an extinct species of walrus, for example, as far south as Florida. Walrus! In Florida!

Seals, sea lions, and walruses have changed in response to climate, predator and human pressures, and other shifts as yet unknown to us. Their stories continue to evolve, and many historic gaps remain.

Image: Elizabeth Bradfield

What we do know is that millions of individual pinnipeds swim the world’s oceans. They are an important part of their ecosystem both historically and today, both in ways we can codify and ways we’re still trying to understand.


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