A prehistoric 15-foot-longwhale that sucked prey intoits mouth represents a keymissing puzzle piece con-cerning the evolution of to-day’s huge fi��lter-feedingwhales, scientists said onThursday.

The researchers de-scribed fossils unearthed inOregon of a whale namedMaiabalaena nesbittae thatlived 33 million years agoand possessed neither teethnor baleen, the materialthat modern fi��lter-feedingwhales use to strain largeamounts of tiny prey out ofthe water for food.

They called Maiabalae-na, meaning “motherwhale,” a surprising inter-mediate evolutionary stagebetween modern baleenwhales and their toothedancestors. Maiabalaenaconsumed fi��sh and squid bysucking them into itsmouth.

The evolutionary stepsthat led to modern baleenfi��lter-feeding giants like theblue whale, the earth’s lar-gest-known animal, had re-mained unclear.

Baleen is a fl��exible mate-rial made of keratin, thesame stuff�� found in hair and

fi��ngernails.One leading hypothesis

had been that in the earlystages of baleen whales' evo-lution, they possessed bothteeth and baleen before be-coming toothless. Maiaba-laena's position on thewhale family tree, the re-searchers said, indicatesthat tooth loss preceded ba-leens by millions of years.

“This fossil demonstratesthat the loss of teeth and theorigin of baleen are separateevolutionary changes, andthat the two changes did notoverlap,” said Nick Pyenson,curator of the SmithsonianInstitution’s National Mu-seum of Natural History.

The fi��rst whales evolvedfrom wolf-like land ances-tors roughly 50 millionyears ago. All early whaleshad teeth.

Ancient whale a key linkto evolutionary puzzleMaiabalaena nesbittae was toothlessReutersWASHINGTON

Maiabalaena nesbittae