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Whales: Evolution & Fossil Record

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Mighty_Emperor

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I always say this is one of the most convincing palaeontological cases to demonstrate evolution - see Stephen Jay Gould's essay "Hooking Leviathan by Its Past" on it in "Dinosaur in a Haystack" and now they have made more finds linking the fossils with the DNA:

Fossil study links whales and hippos

Now-vanished cousin was ‘missing link,’ scientists say

Updated: 7:03 p.m. ET Jan. 24, 2005

WASHINGTON - A second look at some 40-million-year-old fossils provides a “missing link” to suggest that the closest living relative of whales is the hippo, a group of scientists said Monday.

Although the hippopotamus does not seem a likely relative of whales, genetic study has suggested they are close. Now, a team at the University of California at Berkeley, the University of Poitiers in France and the University of N’djamena in Chad say they have found more evidence in the fossil record.

“The problem with hippos is, if you look at the general shape of the animal it could be related to horses, as the ancient Greeks thought, or pigs, as modern scientists thought,” researcher Jean-Renaud Boisserie said in a statement.

In Greek the name hippopotamus means “river horse.”

“But cetaceans — whales, porpoises and dolphins — don’t look anything like hippos. There is a 40-million-year gap between fossils of early cetaceans and early hippos,” Boisserie added.

The earliest cetacean fossils date back 53 million years ,while the first hippopotamus fossils date to about 16 million years.

Writing in the Proceedings of the National Academy of Sciences, Boisserie and colleagues propose a new theory that whales and hippos had a common water-loving ancestor that lived 50 million to 60 million years ago.

From it evolved two groups — the early cetaceans, which gradually moved into the water full-time, and a large and diverse group of piglike animals called anthracotheres.

This proposed family tree of modern whales and their first cousin, the hippopotamus, shows how the now-extinct anthracotheres serve as the link between their distant ancestors.

These animals flourished, forming 37 distinct genera across the world before dying out and leaving just one descendant 2.5 million years ago — the hippopotamus.

The theory would class whales, dolphins and porpoises with cloven-hoofed mammals such as cattle, pigs, and camels.

Boisserie argues that some of the older, time-tested ways of classifying animals by body shape and even teeth are not always the most accurate. He and the other researchers based their reinterpretation of the fossil record on molecular findings going back to the mid-1980s, which saw genetic similarities in the blood proteins and DNA of hippos and whales.
Copyright 2005 Reuters Limited.
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I was under the impression that whales decended from mesonychids, as indicated in the Jay Gould article;
as far as I know these primitive animals were no closer related to hippos than to sheep, or camels.
 
I reccomend a book by Carl Zimmer - "At the Water's Edge: Fish With Fingers, Whales With Legs." It thrashes out the artiodactyl/mesonyschid (sp?) argument pretty well. There's also a good summary in "The Ancestor's Tale" by Richard Dawkins, which is a truly fabulous and fascinating and wonderful book anyway. Even if Dawkins usually gets on your nerves for being so dogmatic, read it. My copy has fallen to bits from reading, which is a bummer as it isn't actually mine, but the property of the library. That'll be twenty five pounds, please, madame.
 
Exceptional Whale Fossil Found in Egyptian Desert:

19 Hours,22 minutes Ago


[Science News] CAIRO - An American paleontologist and a team of Egyptians have found the most nearly complete fossilized skeleton of the primitive whale Basilosaurus isis in Egypt's Western Desert, a university spokesman 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) southwest of Cairo, spokesman Karl Bates told Reuters.

"His feeling is that it's the most complete -- the whole skeleton from stem to stern," said Bates.

The skeleton, which is 50 feet long, could throw light on why there are so many fossilized 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 paleontologists 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.

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"The research team will use the new skeleton to study how it lived and swam, and possibly to learn why it 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 fossilized sharks and bony fish.

It is a protected area to be developed as a national park under an Italian-Egyptian cooperative program and it has been nominated as a UNESCO World Heritage site because of its natural beauty and scientific importance.
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Another aquatic mammal fossil causes a stir:
'Jurassic beaver' found in China

The discovery of a fossil beaver that lived when the dinosaurs ruled the Earth could challenge some currently accepted ideas on mammal evolution.

Castorocauda lutrasimilis, which was unearthed in China, is a species previously unknown to science.

It dates back to 164 million years ago, a time when mammals were thought to be primitive creatures confined to land.

But this animal was adapted to life in water, meaning scientists may now have to rethink their theories.

The fossil was found in the Middle Jurassic Jiulongshan Formation, a deposit rich in the remains of dinosaurs, early insects and other organisms.

Like modern beavers, the creature had fur, a broad scaly tail, and webbed feet for swimming. It was about the size of a small female platypus and had seal-like teeth for eating fish.

Aquatic mammal

Such advanced features have surprised many scientists, suggesting mammals that lived during the hey-day of the dinosaurs had already conquered a variety of environments.

The mammals of the time were once thought to be largely primitive shrew-like creatures, scuttling at the feet of dinosaurs, and only flourishing when the dinosaurs died out some 65 million years ago.

Commenting on the find, revealed in the journal Science, Thomas Martin of the Forschungsinstitut Senckenberg in Frankfurt, Germany, said it showed mammals had conquered the water 100 million years earlier than previously thought.

"This exciting fossil is a further jigsaw-puzzle piece in a series of recent discoveries, demonstrating that the diversity and early evolutionary history of mammals were much more complex than perceived less than a decade ago," he wrote.

http://news.bbc.co.uk/1/hi/sci/tech/4748058.stm
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whales

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) southwest of Cairo
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Good place to start looking.
 
Whale fossil sports fierce teeth
By Elli Leadbeater



The whale used large eyes to hunt prey (Image: R Start, Museum of Victoria)
Palaeontologists have discovered a bizarre whale fossil in Australia with a set of fearsome teeth.

The specimen has surprised scientists because it belongs to the group known as baleen whales.

Modern day baleen whales are all placid, plankton eaters, but the new fossil shows the group were not always the ocean's gentle giants.

Details of the 25 million-year-old find appear in the journal Proceedings of the Royal Society B.

It looks like the teeth were not used for filter feeding

Mark Uhen, Cranbrook Institute of Science
The small, large-eyed baleen whale used a fully developed set of teeth to hunt its prey.

Scientists had thought that two groups of ancient whales evolved drastically different eating habits more than 34 million years ago.

They believed ancient whales that fed by filter feeding evolved to become today's enormous but passive baleen whales, and those that hunted became the ocean's giant predators, the toothed whales.

Toothed whales include the killer whale, sperm whale and dolphin, whereas baleen whales are typified by the humpback and blue whale.

The new specimen shows that ancient baleen whales probably hunted prey like their toothed relatives.

Big beast

Modern-day baleen whales are named after their characteristic baleen, a comb-like structure between their jaws which allows them to filter tiny plankton from the sea to eat. Baleen is made of a substance called keratin, just like our fingernails and hair.

"Specialised skull features tell us that this fossil is undoubtedly a baleen whale," said lead researcher Erich Fitzgerald of the University of Monash in Victoria, Australia.

"Surprisingly, it appears that the original features of baleen whales did not include the filter-feeding apparatus."

Instead, the newly-discovered ancient whale probably used its large, sharp teeth to capture and chew prey, which it located using its large eyes.



The whale probably used its sensitive hearing to hunt (Image: Erich MG Fitzgerald)


"It's always been known that ancient baleen whales had teeth, but this fossil is very important because it looks like the teeth were not used for filter feeding," commented Mark Uhen, head of research at the Cranbrook Institute of Science in Michigan, US.

The fossil represents a previously unknown species, named Janjucetus hunderi after its teenage finder Staumn Hunter, who noticed it in an exposed boulder while surfing in 1997.

Janjucetus hunderi lived between 25 and 9 million years ago after the last common ancestor of the toothed and baleen whales.

The species also has unusual hearing. Unlike modern baleen whales, Jujentus' hearing was probably specialised to detect very high-pitched sounds. This is similar to toothed whales, who now "echolocate", producing high-pitched soundwaves and listening to the echos to find prey.

Janjucetus' living descendents, the baleen whales, appear to have lost this ability, possibly because they no longer hunt large prey. Instead, their ears detect the very low-frequency bass sounds which we associate with whalesong.

Despite its high-frequency hearing, the unusually large eyes of Janjucetus suggest that it probably used sight to find food items.




http://news.bbc.co.uk/2/hi/science/nature/4797679.stm
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Whale fossil is found in vineyard
By Christian Fraser
BBC News, Rome

The biggest whale fossil ever discovered in Italy has been found in one of the country's finest vineyards.

The five-million-year-old skeleton, 33ft (10m) in length, was dug up in the northern grape-growing area of Tuscany.

The vineyards of Castello Banfi, where the bones were uncovered, produce the famed Brunello de Montalcino wine, one of Italy's most prized.

The whale remains were discovered by a fossil hunter who was given special permission to poke around the vines.

Rich soil

The skeleton appears to be complete and, for the last month, palaeontologists from the University of Florence have been carefully digging around the terraces to extract it in one piece.

Millions of years ago, Tuscany was under water and Castello Banfi was the sea bed.

The vineyard owner, Cristina Mariani, is delighted.

"It reminds us "that this rich soil is composed of nutrients and minerals deposited millions of years ago," she says.

"It's that special earth that gives complexity to our wines."

So, if you are lucky enough to ever taste a Brunello, just savour it for that extra moment, and remember that beneath the old vines that produced it - there was an even bigger old whale.

http://news.bbc.co.uk/1/hi/world/europe/6482859.stm
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"..an earthy bouquet, with an aftertaste of blubber!" :D
 
Some real wine-tasters' comments:

Sesti Brunello de Montalcino - Notes of cherries.

Valdicava Brunello de Montalcino - Rustic. Bad nose. End of Story :shock:

Tenuta de Caparzo - Brunello di Montalcino - The nose boasted ripe fruit aromas of strawberry, cassis, cherry. Once in the mouth more cassis fruit and candied cherries carried through the mid-palette. But this is definitely not a fruit bomb. Oak provides for a velvety mouthfeel and soft tannins provide structure.

Lisini Brunello di Montalcino, 2001 - A complex, polished, silky wine with notes of cherries, plums, red berries and pepper. Sweet fruit balances abundant tannins.

Frescobaldi Castelgiacondo Brunello di Montalcino, 2001 - Multi-layered aromas of dark cherries, plums, and tobacco. A modern wine with crisp acidity balancing pulpy fruit and chewy tannins.

Fuligni Brunello de Montalcino, 2001 - a highly perfumed nose suggesting dried flowers and gingerbread. Dense, concentrated berry and mineral flavours.

So, sadly, no blubber, not even a hint of krill!
 
Another whale fossil.

The fossil of a 43-million-year-old whale with four legs, webbed feet and hooves has been discovered in Peru.

Palaeontologists believe the marine mammal's four-metre-long (13 ft) body was adapted to swim and walk on land. With four limbs capable of carrying its weight and a powerful tail, the semi-aquatic whale has been compared to an otter or a beaver. Researchers believe the discovery could shed light on the evolution of the whale and how it spread.

"This is the most complete specimen ever found for a four-legged whale outside of India and Pakistan," Dr Olivier Lambert, a scientist at the Royal Belgian Institute of Natural Sciences and co-author of the study, said.

https://www.bbc.com/news/science-environment-47822228
 
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