Today's baleen whales (Mysticetes) support their massive bodies by filtering huge volumes of small prey from seawater using comb-like baleen in their mouths much like a sieve. But new evidence reported in the journal Current Biology on May 10 based on careful analysis of a 34-million-year-old whale skull from Antarctica -- the second-oldest "baleen" whale ever found -- suggests that early whales actually didn't have baleen at all. Their mouths were equipped instead with well-developed gums and teeth, which they apparently used to bite large prey.
"Llanocetus denticrenatus is an ancient relative of our modern gentle giants, like humpback and blue whales," says Felix Marx of the Royal Belgian Institute of Natural Sciences. "Unlike them, however, it had teeth, and probably was a formidable predator."
"Until recently, it was thought that filter feeding first emerged when whales still had teeth," adds R. Ewan Fordyce at the University of Otago in New Zealand. "Llanocetus shows that this was not the case."
Like modern whales, Llanocetus had distinctive grooves on the roof of its mouth, the researchers explain, which usually contain blood vessels that supply the baleen. In Llanocetus, however, those grooves cluster around tooth sockets, where baleen would have been useless and at risk of being crushed.
"Instead of a filter, it seems that Llanocetus simply had large gums and, judging from the way its teeth are worn, mainly fed by biting large prey," Marx says. "Even so, it was huge: at a total body length of around 8 meters, it rivals some living whales in size."
Materials provided by Cell Press.
(Score: 0) by Anonymous Coward on Sunday May 13 2018, @02:42PM
has teeth.