Paleoparadoxia is a genus of large, herbivorous marine mammal

Mammal

Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...

s that inhabited the northern Pacific coastal region during the Miocene

Miocene

The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...

 epoch (20 to 10 million years ago). It ranged from the waters of Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

 (Tsuyama

Tsuyama, Okayama

is a city located in Okayama, Japan.As of 2003, the city had an estimated population of 89,974 and the density of 484.43 persons per km². The total area was 185.73 km²...

 and Yanagawa

Date, Fukushima

is a city located in northern Fukushima, Japan.As of May 2011, the town has an estimated population of 65,409 and the total area is 265 km².There were nine towns in Date District, Fukushima. On January 1, 2006, five towns in Date District merged to form the city of Date. Merged towns were Hobara,...

), to Alaska

Alaska

Alaska is the largest state in the United States by area. It is situated in the northwest extremity of the North American continent, with Canada to the east, the Arctic Ocean to the north, and the Pacific Ocean to the west and south, with Russia further west across the Bering Strait...

 to the north, and down to Baja California

Baja California

Baja California officially Estado Libre y Soberano de Baja California is one of the 31 states which, with the Federal District, comprise the 32 Federal Entities of Mexico. It is both the northernmost and westernmost state of Mexico. Before becoming a state in 1953, the area was known as the North...

, Mexico

Mexico

The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...

. It is believed there are only two complete fossil

Fossil

Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

 skeletons in the world, one at Fukushima Museum in Fukushima Prefecture

Fukushima Prefecture

is a prefecture of Japan located in the Tōhoku region on the island of Honshu. The capital is the city of Fukushima.-History:Until the Meiji Restoration, the area of Fukushima prefecture was known as Mutsu Province....

 Japan and one at the SLAC National Accelerator Laboratory

SLAC National Accelerator Laboratory

The SLAC National Accelerator Laboratory, originally named Stanford Linear Accelerator Center, is a United States Department of Energy National Laboratory operated by Stanford University under the programmatic direction of the U.S...

 in Northern California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

.

Paleoparadoxia is thought to have fed primarily on seaweed

Seaweed

Seaweed is a loose, colloquial term encompassing macroscopic, multicellular, benthic marine algae. The term includes some members of the red, brown and green algae...

s and sea grasses. The jaw

Jaw

The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term jaws is also broadly applied to the whole of the structures constituting the vault of the mouth and serving to open and close it and is part of the body plan of...

s and the angle of the teeth resemble a backhoe

Backhoe

A backhoe, also called a rear actor or back actor, is a piece of excavating equipment or digger consisting of a digging bucket on the end of a two-part articulated arm. They are typically mounted on the back of a tractor or front loader...

 bucket. Its bulky body was well adapted for swimming and underwater foraging, but not for extended deep-sea living or deep diving. Like the modern-day seal

Pinniped

Pinnipeds or fin-footed mammals are a widely distributed and diverse group of semiaquatic marine mammals comprising the families Odobenidae , Otariidae , and Phocidae .-Overview: Pinnipeds are typically sleek-bodied and barrel-shaped...

, Paleoparadoxia probably came on shore for breeding and basking in the sun

Sun

The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...

. It also resembled the Desmostylus

Desmostylus

Desmostylus is a monotypic extinct genus of herbivorous mammal of the family Desmostylidae living from the Chattian stage of the Late Oligocene subepoch through the Late Miocene subepoch and in existence for approximately ....

.

External links

• Stanford's SLAC Paleoparadoxia, identified by Charles Repenning
  Charles Repenning
  Charles Repenning was an American paleontologist and zoologist noted for his work on shrews, fossil rodents, modern pinnipeds and their extinct relatives, the Desmostylia...
  
   (much thanks to Adele Panofsky, Dr. Wolfgang Panofsky's wife for her assembly of the bones of the Paleoparadoxia found and uncovered at SLAC)
• More uncovering at SLAC, and Adele Panofsky
• Picture of Paleoparadoxia
• Another picture
• Reclassification of SLAC specimen as P. repenningi
• SLAC coverage of the renaming