Puijila darwini

Overview

Puijila darwini is an early pinniped relative with a long trunk and tail and four feet rather than flippers. It is presented as having an otter-like body and a head recalling the seal lineage. A fossil from an island in today's Arctic reveals a different stage in the evolution of marine mammals.^[4][1]

Key facts

The lake in which the fossil was preserved lay inside an old impact crater. First the crater formed, then lake sediments accumulated and the animal's bones were preserved. Even rocks at the same location hold stories from different times.^[5][3]

Time and place

It was discovered in lake sediments on Devon Island in the present-day Canadian Arctic. The institution presents it as material from around 24–20 million years ago, around the beginning of the Miocene. The fossil evokes an older lake ecosystem in what is now the Arctic.^[2][3]

The time range describes source context, not the complete duration of this species.

Size, form and skeleton

The trunk and tail are long, and each of the four limbs ends in a foot. The abstract of the original description explains that the finger and toe bones are flattened. This body can be compared alongside the flipper-shaped limbs of living pinnipeds.^[4][1]

The body length presented in institutional educational material is about 110 cm.^[2]

Habitat and reproduction

Aquatic adaptation is explored through the body of a four-footed animal found in lake sediments. Its relatively large hands and forelimbs, long trunk, and tail are compared. This raises questions about how the feet of mammals using water differed.^[4][1]

Fossil discovery

The museum presents the story of the discovery of a nearly complete skeleton on Devon Island. The original 2009 description explained this animal in connection with early pinniped evolution. A discovery in the distant Arctic became part of a broader story of mammals moving between land and water.^[4][3]

References

1. Field Museum — The body of Puijila
2. Arctic Through the Ages: Puijila card
3. Carnegie Museums (2021) — Stories of discoveries during excavation
4. Rybczynski et al. (2009) — Puijila, an early Arctic relative of pinnipeds
5. 2023 study — Haughton crater and lake sediments
6. Mitchell (1968) — The skull and teeth of Imagotaria

Research questions

When did the feet of seal relatives change into flippers? The four feet of Puijila are compared with the limbs of early pinnipeds. Reading the environment of the fossil-bearing strata alongside body form allows several stages of aquatic adaptation to be explored.^[4][1]

Observation

Move your gaze from the otter-like elongated trunk to the four feet and long tail. Picturing them alongside a seal's flippers reveals different bodies among similar relatives.^[1]