http://scienceblogs.com/laelaps/2009/04/puijila_darwini_a_significant.php

http://nature.ca/puijila/fb_e.cfm 22ma

Arctic as center of evolution? Note Bering land bridge, warm
http://nature.ca/puijila/fb_go_e.cfm

http://scienceblogs.com/notrocketscience/2009/04/puijila_the_walking_seal_beauti\
ful_transitional_fossil.php

Possibly a bottom walker + dog-paddle swimmer? (appears to have dense limb
bones)

long narrow tails not selected for in vertical divers, broad flat medium/short
length tails selected for in vertical divers


miocene mustelids

Bipedal stance?:
http://www.nmb.bs.ch/sammlungen/geowissenschaftliche-sammlung/palaeontologie-wir\
beltiere/aquitane-saeugerfaunen-allierbecken.htm

Potamotherium, resembled a modern giant otter, and was 1.5 metres (5 ft) long,
with an elongated, slender body and short legs. With a flexible backbone and a
streamlined shape, it was probably a good swimmer. Analysis of fossils suggests
that Potamotherium had a poor sense of smell, but made up for this with good
vision and hearing.[2]


http://en.wikipedia.org/wiki/Enaliarctos 23ma
http://en.wikipedia.org/wiki/Enaliarctos_emlongi
Investigations of the biomechanics of Enaliarctos indicate that it used both its
forelimbs and hindlimbs during swimming. Modern fur seals and sea lions only use
their forelimbs, while true seals primarily use their hindlimbs for aquatic
propulsion; lastly, the extant walrus uses both fore- and hindlimbs for
swimming.

http://otters.livejournal.com/34200.html
Semantor etc.



http://en.wikipedia.org/wiki/Sea_otter 5ma
It is unique among the mustelids in not making dens or burrows, in having no
functional anal scent glands,[9] and in being able to live its entire life
without leaving the water.[10] The only member of the genus Enhydra, the sea
otter is so different from other mustelid species that as recently as 1982, some
scientists believed it was more closely related to the earless seals.[11]
Genetic analysis indicates that the sea otter and its closest extant relatives,
which include the African speckle-throated otter, Eurasian otter, African
clawless otter and oriental small-clawed otter, shared an ancestor approximately
5 million years ago (mya).[12]

Fossil evidence indicates that the Enhydra lineage became isolated in the North
Pacific approximately 2 mya, giving rise to the now-extinct Enhydra macrodonta
and the modern sea otter, Enhydra lutris.[3] The sea otter evolved initially in
northern Hokkaidō and Russia, then spread east to the Aleutian Islands,
mainland Alaska, and down the North American coast.[13] In comparison to
cetaceans, sirenians, and pinnipeds, which entered the water approximately 50
mya, 40 mya, and 20 mya, respectively, the sea otter is a relative newcomer to a
marine existence.[14] In some respects, however, the sea otter is more fully
aquatically adapted than pinnipeds, which must haul out on land or ice to give
birth.[15]



http://www.foresthart.com/seamink.html
He described the sea mink as being twice the size of the "woods mink" with
coarse reddish brown fur and being extremely fat.

http://wtfaculty.wtamu.edu/~rmatlack/Mammalogy/puma_concolor_skull.htm
Puma shearing teeth (crab eating seal has similar teeth but eats krill)