Re: Janjucetus hunderi (RE: Ancient Whale Broke all the Rules)

[Roberto Takata <rmtakata@gmail.com>]

The author compare with another seal - leopard seal:

Proceedings of the Royal Society B: Biological Sciences
ISSN: 0962-8452 (Paper) 1471-2954 (Online)
Issue: FirstCite Early Online Publishing
DOI: 10.1098/rspb.2006.3664

A bizarre new toothed mysticete (Cetacea) from Australia and the early
evolution of baleen whales

Erich M.G. Fitzgerald AFF1 AFF2

AFF1 School of Geosciences, Monash University, Clayton, Vic. 3800, Australia
AFF2 Museum of Victoria, GPO Box 666, Melbourne, Vic. 3001, Australia

Abstract:

Extant baleen whales (Cetacea, Mysticeti) are all large filter-feeding
marine mammals that lack teeth as adults, instead possessing baleen,
and feed on small marine animals in bulk. The early evolution of these
superlative mammals, and their unique feeding method, has hitherto
remained enigmatic. Here, I report a new toothed mysticete from the
Late Oligocene of Australia that is more archaic than any previously
described. Unlike all other mysticetes, this new whale was small, had
enormous eyes and lacked derived adaptations for bulk filter-feeding.
Several morphological features suggest that this mysticete was a
macrophagous predator, being convergent on some Mesozoic marine
reptiles and the extant leopard seal (Hydrurga leptonyx). It thus
refutes the notions that all stem mysticetes were filter-feeders, and
that the origins and initial radiation of mysticetes was linked to the
evolution of filter-feeding. Mysticetes evidently radiated into a
variety of disparate forms and feeding ecologies before the evolution
of baleen or filter-feeding. The phylogenetic context of the new whale
indicates that basal mysticetes were macrophagous predators that did
not employ filter-feeding or echolocation, and that the evolution of
characters associated with bulk filter-feeding was gradual.
--------------

[]s,

Roberto Takata
On 8/16/06, Mikko K. Haaramo <mikko.haaramo@helsinki.fi> wrote:
> Molar teeth look more like those of the crab-eating seal (_Lobodon
> carcinophagus_).
>
> http://images.google.fi/images?q=Lobodon
>
> Maybe an early attemp of krill-eating. :)
>
> --Mikko Haaramo
>
>
> -----Original Message-----
> From: owner-DINOSAUR@usc.edu [mailto:owner-DINOSAUR@usc.edu] On Behalf Of
> David Marjanovic
> Sent: 16. elokuuta 2006 14:52
> To: DML
> Subject: Re: Janjucetus hunderi (RE: Ancient Whale Broke all the Rules)
>
> > An exceedingly bizarre animal - it's a baleen (stem-group
> > mysticete)whale sans baleen which was trying to rip-off the
> > sauropterygia or perhaps Dakosaurus.
>
> It looks a lot like *Dakosaurus*!
>
> But... I thought toothed predatory mysticetes from the Oligocene were
> nothing new? So just the completeness and the huge unmammalian eyes are new?