Brygmophyseter
Encyclopedia
Brygmophyseter is an extinct genus
of toothed whale
in the sperm whale family with one species Brygmophyseter shigensis. When first described, this species was placed in an extinct form genus
Scaldicetus of toothed whale, as Scaldicetus shigensis). In 2006, it was transferred to a new genus Naganocetus as Naganocetus shigensis, however later in 2006, it was then moved to Brygmophyseter leaving Naganocetus as a nomen nudum
name.
word brygmos, which means "biting" or "gnashing", combined with suffix Physeter, which is the generic name of the living sperm whale, and which is also the Greek word for "blower". This has led to the occasional vernacular term "biting sperm whale" being given to the species in popular culture.
in Japan
in 1988 by the residents of Shiga-mura with assistance from staff of Shiga Fossil Museum. The specimen is nearly complete, and includes a 140 cm long skull
. This specimen came from 15-14 million years old sediment
s. Unlike the extant giant sperm whale, Physeter macrocephalus, which has teeth in its lower jaw
only; Brygmophyseter has 12 functional teeth on each side of the lower jaws and 12 functional teeth on each side of the upper jaws. The holotype specimen is currently on display in Gunman Museum of Natural History in Japan.
to track and disorient a prey item in deep waters, like the modern age Sperm Whale
s. It may also have used its large head to ram a potential opponent during conflict. Brygmophyseter would also have lived in social groups called pods, and probably hunted in packs, like modern age Orcas.
, pinniped
s, giant squid
, and other cetaceans.
It shall be noted that remains of undetermined mysticeti whales have been found in the same region where the holotype specimen was found, however a predator-prey relationship between Brygmophyseter and these whales have not been inferred in the scientific literature.
was likely a primary predator of the sperm whales
. A large number of cetacean bone
s have been found with large bite marks (deep gashes) in them, which were caused by teeth that belong to C. megalodon.
- as an adversary of the C. megalodon. The history of its finding and probable behavior have also been explored within the show.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of toothed whale
Toothed whale
The toothed whales form a suborder of the cetaceans, including sperm whales, beaked whales, dolphins, and others. As the name suggests, the suborder is characterized by the presence of teeth rather than the baleen of other whales.-Anatomy:Toothed whales have a single blowhole on the top of the head...
in the sperm whale family with one species Brygmophyseter shigensis. When first described, this species was placed in an extinct form genus
Form taxon
Form classification is the classification of organisms based on their morphology, which does not necessarily reflect their biological relationships...
Scaldicetus of toothed whale, as Scaldicetus shigensis). In 2006, it was transferred to a new genus Naganocetus as Naganocetus shigensis, however later in 2006, it was then moved to Brygmophyseter leaving Naganocetus as a nomen nudum
Nomen nudum
The phrase nomen nudum is a Latin term, meaning "naked name", used in taxonomy...
name.
Etymology
The genus name is a combination of the GreekGreek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
word brygmos, which means "biting" or "gnashing", combined with suffix Physeter, which is the generic name of the living sperm whale, and which is also the Greek word for "blower". This has led to the occasional vernacular term "biting sperm whale" being given to the species in popular culture.
Holotype specimen
The holotype specimen (SFM-0001) was excavated from Bessho Formation in Nagano PrefectureNagano Prefecture
is a prefecture of Japan located in the Chūbu region of the island of Honshū. The capital is the city of Nagano.- History :Nagano was formerly known as the province of Shinano...
in 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...
in 1988 by the residents of Shiga-mura with assistance from staff of Shiga Fossil Museum. The specimen is nearly complete, and includes a 140 cm long skull
Skull
The skull is a bony structure in the head of many animals that supports the structures of the face and forms a cavity for the brain.The skull is composed of two parts: the cranium and the mandible. A skull without a mandible is only a cranium. Animals that have skulls are called craniates...
. This specimen came from 15-14 million years old sediment
Sediment
Sediment is naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of fluids such as wind, water, or ice, and/or by the force of gravity acting on the particle itself....
s. Unlike the extant giant sperm whale, Physeter macrocephalus, which has teeth in its lower 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...
only; Brygmophyseter has 12 functional teeth on each side of the lower jaws and 12 functional teeth on each side of the upper jaws. The holotype specimen is currently on display in Gunman Museum of Natural History in Japan.
Size
The holotype specimen is around 7 metres (23 ft) long. However, in popular culture, Brygmophyseter have been depicted significantly larger in size — up to 12 metres (39 ft) long.Behavior and predatory capabilities
Brygmophyseter was likely among the apex predators of its time. It packed a formidable jaws armed with teeth up to 14 cm (5.5 inches) long. It may have employed sonarSonar
Sonar is a technique that uses sound propagation to navigate, communicate with or detect other vessels...
to track and disorient a prey item in deep waters, like the modern age Sperm Whale
Sperm Whale
The sperm whale, Physeter macrocephalus, is a marine mammal species, order Cetacea, a toothed whale having the largest brain of any animal. The name comes from the milky-white waxy substance, spermaceti, found in the animal's head. The sperm whale is the only living member of genus Physeter...
s. It may also have used its large head to ram a potential opponent during conflict. Brygmophyseter would also have lived in social groups called pods, and probably hunted in packs, like modern age Orcas.
Dietary preferences
Brygmophyseter is assumed to have preyed upon a variety of animals including fishFish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
, pinniped
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...
s, giant squid
Giant squid
The giant squid is a deep-ocean dwelling squid in the family Architeuthidae, represented by as many as eight species...
, and other cetaceans.
It shall be noted that remains of undetermined mysticeti whales have been found in the same region where the holotype specimen was found, however a predator-prey relationship between Brygmophyseter and these whales have not been inferred in the scientific literature.
Potential Threats
The shark species C. megalodonMegalodon
The megalodon and ὀδούς ) is an extinct species of shark that lived roughly from 28 to 1.5 million years ago, during the Cenozoic Era .The taxonomic assignment of C...
was likely a primary predator of the sperm whales
Sperm whale family
Physeteroidea is a superfamily including just three living species of whale; the Sperm Whale, in the genus Physeter, and the Pygmy Sperm Whale and Dwarf Sperm Whale, in the genus Kogia...
. A large number of cetacean bone
Bone
Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...
s have been found with large bite marks (deep gashes) in them, which were caused by teeth that belong to C. megalodon.
In popular culture
Brygmophyseter is featured in an episode of Jurassic Fight ClubJurassic Fight Club
Jurassic Fight Club is a paleontology-based television series on History which premiered in the USA in July 2008.-Summary:Scientists study the battles of prehistoric creatures, such as dinosaurs, before they went extinct. Each episode features a forensic-styled breakdown of a prehistoric battle...
- as an adversary of the C. megalodon. The history of its finding and probable behavior have also been explored within the show.
Related species
- AulophyseterAulophyseterAulophyseter is an extinct genus of sperm whale from the Miocene formations of the West and East coasts of North America as well as the Patagonian region of South America...
- OrycterocetusOrycterocetusOrycterocetus is an extinct genus of sperm whale from the Miocene.-Sources:* Cenozoic Seas: The View From Eastern North America by Edward J. Petuch* Marine Mammals: Evolutionary Biology by Annalisa Berta and James L. Sumich...
- AcrophyseterAcrophyseterAcrophyseter is a genus of stem-sperm whales that lived around 6 million years ago.-Description:Acrophyseter is derived from the Greek akros, meaning acute, which describes the short, pointed upturned snout, and Physeter, the scientific name for sperm whales. But unlike today's sperm whales, A...
- ZygophyseterZygophyseterZygophyseter varolai is an extinct cetacean, similar to the sperm whale. The common name of "killer sperm whale" refers both to its relation to modern day sperm whales, and to its similarity in size to and its "probable similar feeding adaptation to the extant delphinid killer whale ".The...
- Livyatan melvilleiLivyatan melvilleiLivyatan melvillei is an extinct species of physeteroid whale, which lived during the Miocene epoch, approximately 12-13 million years ago.- Discovery :...
External links
- Brygmophyseter Skeleton on display in a Japanese Museum
- Brygmophyseter, ancient killer sperm whale
- Age of Mammals - Specimen Spotlight - Aulophyseter morricei (This video also contains information about Brygmophyseter)
