On October 17 th, 2011, the Post Authority of Peru - Servicios Postales del Peru SA (Serpost) -
continued their multi-year series "Prehistoric animals - Fossils" (Animales Prehistoricos - Fosiles) started in 2004.
This year the Souvenir-Sheet shows scientific reconstruction and fossil of prehistoric sperm whale -
Levyatan melvillei.
The reverse side
of the Souvenir-Sheet is numbered.
In November 2008, fossil remains of a giant, prehistoric whale were discovered,
by international paleontologists team, in the
middle of the Peruvian desert 35 km south-west of the city of Ica,
from the Pisco Formation at Cerro Colorado, Peru.
Klaas Post, a researcher for the Natural History Museum Rotterdam in the Netherlands,
stumbled across them on the final day of a field trip.
The remains include a partially preserved 3 meters long skull (75% complete)
with teeth and mandible of a "sea monster" three times the size of a modern day killer whale.
The species was described two years later and named Livyatan melvillei,
after the original Hebrew word for a mythical sea monster - Livyatan -
and Herman Melville (1819–1891), the author of the novel Moby Dick,
about a white bull sperm whale.
The teeth of Livyatan melvillei were so large, each around 12 centimetres in
diameter and up to 36 centimetres in length, it was initially assumed they were elephant tusks.
However, there were no elephants in South America before 3 million years ago, while the specimens found
have an estimated age between 9 and 10 million years old.
Professor Jelle Reumer from Natural History (Natuurhistorisch) Museum Rotterdam, the Netherlands,
one of the team of scientists who found the fossil explained:
The size of its teeth indicate that the mammal fed on large prey,
possibly baleen whales which were plentiful at the time of the
Livyatan's existence around 12 million to 13 million years ago, in the
middle of the Miocene Age.
After the Miocene it became relatively much colder.
At the same time the baleen whales became bigger probably to escape from predation from
these animals, just the way elephants escaped predation by becoming
bigger so they were not eaten by lions any more.
The researchers speculate that Livyatan was able to feed on very large prey up to 8m long.
It would catch the prey in its huge jaws and tear it apart quickly and effectively with
its giant teeth.
Livyatan melvillei was a cetacean that measured about 15 meters in length.
It was a close relative of modern sperm whales, but unlike
those whose diet is based on squid, the Livyatan was possibly
the maximum predator of the food chain thanks to its powerful bite and enormous size.
Paleontologists think that the evolution of this hypercarnivore was favoured by the
great diversity of whales that occurred at that time and that constituted
its main food.
Prehistoric shark Carcharocles megalodon on Souvenir-Sheet of
New Caledonia 1999,
MiNr.: Bl. 22, Scott: 818.
Livyatan differs from current sperm whales in
the enormous size of the temporal fossa
presence of teeth in the jaws
proportionally shorter and more robust skull
method of feeding:
modern sperm whale suck in squid at depths of a kilometre
or more and only have relatively small teeth on their lower jaw.
This great predator coexisted with another colossus of the time, the giant shark
Carcharocles megalodon, whose size is estimated at 13 meters.
Teeth up to 15 cm long of Carcharocles are relatively common in the area where
fossils of Livyatan were discovered.
As a top predator, together with the contemporaneous
giant shark Carcharocles megalodon, it probably had a profound
impact on the structuring of Miocene marine communities.
The fossil of Livyatan melvillei were prepared in Lima, and now are in
collection of the Department of Vertebrate Paleontology of the
Museo de Historia Natural, Universidad Nacional Mayor de San Marcos,
Lima - Peru, under specimen number MUSM 1676.
Casts of three largest teeth are on display at the Natural History Museum Rotterdam,
the Netherlands.
Lambert, O., Bianucci, G., Post, K. et al.
"The giant bite of a new raptorial sperm whale from the Miocene epoch of Peru".
Nature 466, 105–108 (2010). https://doi.org/10.1038/nature09067
Many thanks to
Dr. Peter Voice from Department of Geological and Environmental Sciences, Western Michigan University,
for reviewing the draft page and his very valuable comments.