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Livyatan Melvillei (image painted by Balazs Petheo)

Livyatan Melvillei (image painted by Balazs Petheo)

Behold the terrifying ocean monster, Livyatan Melvillei! This predatory toothed whale lived 12-13 million years ago during the Miocene epoch and grew to 13.5 to 17.5 meters (45–57 feet) in length. A large adult whale could have weighed up to 50 tons. The extinct megapredator is named for Herman Melville and for the Biblical leviathan (“Livyatan” is from the Hebrew word for Leviathan). The great whale’s family is currently listed as “incertae sedis” which means “status uncertain,” a taxonomical place-holder used when biologists are trying to ascertain a creature’s relationship to other related organisms within a larger order.

Livyatan Melvillei

Livyatan Melvillei with smaller baleen whale

In terms of body size, the modern sperm whale is probably slightly longer and heavier, but the livyatan had stronger jaws and much larger teeth. Paleontologists describe the mighty creature as having “the biggest tetrapod bite ever found,” which is no trivial matter, since the tetrapods include all mammals, reptiles (like dinosaurs), amphibians, and birds. Of course plankton feeders (like blue whales and whale sharks) have larger mouths, but the sperm whale and the livyatan have more powerful maws filled with large sharp teeth. The 36 centimeter (1.2 foot) long teeth of livyatan are the largest known teeth from the animal world which were used for eating (which is to say the tusks of elephants, walruses, Odobenocetops, and narwhals tusks were larger, but were not used for biting into plants or animals).

Livyatan Melvillei biting a smaller baleen whale (painting via dino-rider)

Livyatan Melvillei BITING a smaller baleen whale (painting via dino-rider)

Livyatan Melvillei presumably swam the deep blue ocean hunting for seals, dolphins, baleen whales and whatever other sea creature was large enough to command its attention (giant sharks, huge squid, huge fish, and bizarre giant birds?). Like the sperm whale it seems to have had a spermaceti organ in its head although it is unclear if this was used for echolocation, auditory signaling, or aggressive male sexual display (i.e. head-butting).  It must have been quite a (horrifying) sight to see one of these giant monsters biting apart a 10 meter (33 foot) long baleen whale. Sadly, the ever-changing dynamic of ocean life caused the great toothed whale to go extinct at approximately the same time as megalodon, the largest known shark (which was a contemporary of the great whale).  Numerous websites speculate which great animal would have won an ocean duel–which is foolish, since whales are clever animals and thus the obvious victor.

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Rodhocetus (by Pavel Riha)

Rodhocetus (by Pavel Riha)

This endearing beasty is Rodhocetus, a long extinct proto-whale which lived during the mid-Eocene (approximately 40 to 50 million years ago). Rhodhocetus fossils are found in contemporary Pakistan, but the world has changed greatly since the warm Eocene: the creatures did not live on the tops of mountains, but rather in estuaries and shallow seas.

Rodhocetus

Rodhocetus

The early cetaceans shared ancestors with the artiodactyls (cows, pigs, hippos, goats, and suchlike even-toed ungulates) and indeed the first cetaceans, from the beginning of the Eocene, look somewhat like weird squashed hippos or water cows. By the middle of the epoch, however the familial similarities were beginning to fade.

06-14-P-02-G-01-KlausmeyerRodhocetus-full_1

Rodhocetus specimens have elongated hands and feet–which were almost certainly webbed. Their hipbones were not fused to their backbones, which gave them additional speed and maneuverability in the water, where they hunted for fish and squids. Although the creatures were adapted for an aquatic predatory lifestyle, they could still drag themselves up on land, unlike their descendents the modern whales and dolphins. Additionally they still retained fur, and double-pulley heelbones (the latter of which convinced paleontologists that whales and cows are relatives who share an ancestor).

Wadi Al-Hitan, Egypt

In the desolate desert 150 kilometers southwest of Cairo there is a fearsome arid valley (wadi) of cliffs, carved buttes, and sandblasted erratic boulders.  The bleached landscape has an otherworldly emptiness as though it were located on a lifeless alien planet, though if you look closely, the desert is filled with austere furtive life like dorcas gazelles, tiny sand colored lizards, cobras, scorpions, and fennec foxes. The name of the place is even more otherworldly—“Wadi Al-Hitan” which is Arabic for “valley of the whales” and although the great smooth rocks buckling out of the sand might momentarily be taken for the backs of huge whales, the utter absence of the ocean (or of water of any kind) makes the name seem fanciful. The nearby Mount Garet Gohannam (which means mountain of hell because of the way it glows like flames at sunset) seems to be more aptly named.

Whale fossil at Wadi Al-Hitan

However the name of Wadi Al-Hitan is remarkably literal–for the valley contains the remains of hundreds of huge ancient cetaceans which died in the Eocene and were fossilized in the yellowish sandstone.  Forty million years ago the valley was a marine lagoon.  Although the remains of numerous sirenians, sawfish, sharks, rays, sea turtles, marine crocodiles, sea snakes, and even swamp dwelling moeritheriums have been discovered in the wadi, the valley takes its name from the most spectacular and numerous fossils which belong to four different species of primitive whales.  The most commonly discovered fossils belong to Dorudon, which was 3-5 meters long (9-15 feet) and fed on fish and mollusks, and to Basilosaurus, which was 15-22 meter (50-72 foot) and fed on everything else in the ocean.

Basilosaurus was first discovered in Louisiana in the early 19th century.  Its immense size and serpentine form initially convinced naturalists that it was a marine reptile and they misnamed the creature Basilosaurus (which means “king lizard”).  The mistake soon became obvious and Basilosaurus was classified among the Archaeoceti, a paraphyletic suborder of the cetaceans, however the giant kept its dinosaur name.  Different species of Basilosaurus flourished in oceans worldwide during the wet, tropical Eocene and, even though they were obviously very adept at ocean living (indeed rising to the top of the food chain) the creatures betray vestiges of terrestrial living which modern whales have entirely dispensed with. Not only do Basilosaurus fossils have teeth and jaws which retain reatures from their artiodactyl ancestors, they also have tiny vestigial back legs a mere half meter in length (which would scarely help a 22 meter animal get around).  Additionally Basilosaurus was different from modern whales in that it probably moved with eel-like horizontal thrashing of its long tail (modern whales move their flukes vertically).  Basilosaurus probably did not dive very deeply, but moved about near the surface of the oceans hunting for smaller marine animals.

Basilosaurus from “Life in the Ancient Seas Exhibit” at the Smithsonian Institution, National Museum of Natural History

Although Wadi Al-Hitan was discovered by Europeans in 1902-1903, some archaeologists and anthropologists have speculated that it was known long before that and have been irresistibly drawn towards comparing basilosaurus with the giant crocodiles and earth spanning serpent gods which populate ancient Egyptian cosmology.

Detail from painting (Life in the Ancient Seas Exhibit: Smithsonian Institution, National Museum of Natural History)

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