The fossilised jawbone of the oldest whale yet discovered has
confirmed the theory that the giant sea mammals' ancestors were amphibians.
They rested and reproduced on land but dived into rivers and the ocean to
fish for food.
The jawbone, complete with teeth, is 53.5m years old - 3.5m years older than
previous record holder - and was found in the Simla Hills of northern India.
The rock layer which yielded the jawbone is littered with oyster shells and
was
deposited in a shallow ocean that once separated India and
Asia. This is significant because the previous oldest-known whale fossil,
unearthed in Pakistan, lay buried with the remains of only land. Scientists
believed that whales evolved from land-living animals which were tempted
to return to the ocean by the plentiful supply of fish
in the now-disappeared Tethys ocean. The researchers, from the University of
Roorke, India and the University of Michigan, USA, analysed the newly discovered
teeth and found the chemical
composition was halfway between values expected for fresh and marine water.
This, they believe, shows that the first whales swam in rivers, estuaries
and oceans
in search of fish, as well as spending time on land. Modern whales
have become entirely adapted to ocean life, but have retained the need to
breathe. The fossil belongs to a previously unknown genus and species. It has
been named Himalayacetus subathuensis in a report in the Proceedings of the
National
Academy of Sciences. The ocean it once inhabited was destroyed when the Indian
continent collided with Asia, creating the Himalayan mountains.
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8 million-year-old whale fossil found in Maryland
Solomons, Maryland (AP) -- Days after Hurricane Isabel ravaged the cliffs lining St. Mary's River last year, Jeff DiMeglio and his girlfriend went scouring for shark teeth and found what DiMeglio, an experienced fossil hunter, recognized as the rib of a whale. He immediately covered the findings and contacted a museum. Heavy erosion from the storm had unearthed the complete fossilized skull of what paleontologists say was an 8 million-year-old whale. The find is important because little is known about whales of that era, said Stephen Godfrey, curator of paleontology for the Calvert Marine Museum. The remains were shown to the media Thursday at the museum, where scientists are carefully chipping away sediment around the 5.5-foot skull with hopes of one day putting it on display. The hurricane that unearthed the fossil last September was Maryland's worst-ever natural disaster, blamed for dozens of deaths and costing the state and local governments at least $275 million. Isabel's surge collapsed bulkheads and seawalls, exposing parts of shoreline. Most residents were dismayed by the erosion. Not Godfrey: Southern Maryland's cliffs that harbor a rich source of marine fossils, including thousands of prehistoric shark teeth and whale bones. "There is some angst watching the cliffs disappear, but it's great for paleontology," he said. To free the fossil from the ground, scientists swathed it in burlap and plaster-of-paris, creating a hard cast, then called on the Patuxent Naval Air Station. A search-and-rescue team rappelled from a helicopter, attached the fossil to a cable and flew it out. Scientists couldn't find the spine of the 18-foot whale but did recover some vertebrae, a neck bone, a fin and a shoulder blade. The fossil was found in an area where the water would have been shallow, and he believes the whale lived at a time when warm temperatures spread across the Atlantic Ocean. Godfrey thinks it was a baleen whale, but he doesn't know if it was an ancestor of modern baleen whales, like the humpback, or part of an extinct line. There are a few clues to how it may have died. Teeth marks score part of the bone, and the fossilized teeth of giant mako and cow sharks also were found among the bones.
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Whale fossil found in Egyptian desert
Cairo - An American palaeontologist and a team of Egyptians
have found the most complete fossilised skeleton of the primitive whale Basilosaurus
isis in Egypt's Western Desert, a university spokesperson said on Monday. Philip
Gingerich of the University of Michigan excavated the well-preserved skeleton,
which is about 40 million years old, in a desert valley known as
Wadi Hitan (the Valley of the Whales) south-west of Cairo, spokesperson Karl
Bates said. "His feeling is that it's the most complete - the whole
skeleton from stem to stern," said Bates. The skeleton, which is 18
metres long, could throw light on why there are so many fossilised remains
of whales and other
ancient sea animals in Wadi
Hitan and possibly how the extinct animal swam, he said. Basilosaurus isis
is one of the primitive whales known as archaeocetes, which evolved from
land mammals and later evolved into the two types of modern
whale. But it looks like a giant sea snake and the palaeontologists who found
the first archaeocetes thought they were reptiles. Modern whales swim by
moving
their horizontal fluke up and down in the water, while fish swim by lateral
undulations. "The research team will use
the new skeleton to study how it lived and swam, and possibly to learn why
it is so abundant in Wadi Hitan," Gingerich
said in a statement. The statement said the skeleton will go to Michigan
for preservation and replication. The original will then come back to Egypt
for
display. Wadi Hitan is unusually rich in fossil remains from the period, trapped
in a sandstone formation that then formed the sea bed. The fossils include
five species of whale, three species of sea cow, two crocodiles, several
turtles, a sea snake, and large numbers of fossilised sharks and bony fish.
It is a protected area to be developed as a national park under an Italian-Egyptian
co-operative programme and it has been nominated as a Unesco World Heritage
site because of its natural beauty and scientific importance.
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