query: instance_of ginkgo-toothed beaked whale
supports: The even-toed ungulates (order Artiodactyla) are ungulates (hoofed animals) whose weight is borne equally by the third and fourth toes. By contrast, odd-toed ungulates, such as horses, bear their weight primarily on their third toe. The aquatic Cetaceans (whales, dolphins, and porpoises) evolved from even-toed ungulate ancestors, and therefore modern taxonomic classification combines Artiodactyla and Cetacea into Cetartiodactyla. The ginkgo - toothed beaked whale ( Mesoplodon ginkgodens ) is a poorly known species of whale even for a beaked whale , and was named for the unusual shape of its dual teeth . It is a fairly typical - looking species , but is notable for the males not having any scarring . Beaked whales are the members of the family Ziphiidae, which consists of 22 species. These toothed whales are notable for their elongated beaks. Among air-breathing animals, beaked whales are some of the most extreme divers: Cuvier's beaked whales regularly dive for an hour at a depth over , and the longest and deepest foraging dive recorded is 137.5 minutes at . This is the greatest dive-depth known for a mammal. Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. They are an informal grouping within the infraorder Cetacea, usually excluding dolphins and porpoises. Whales, dolphins and porpoises belong to the order Cetartiodactyla with even-toed ungulates and their closest living relatives are the hippopotamuses, having diverged about 40 million years ago. The two parvorders of whales, baleen whales (Mysticeti) and toothed whales (Odontoceti), are thought to have split apart around 34 million years ago. The whales comprise eight extant families: Balaenopteridae (the rorquals), Balaenidae (right whales), Cetotheriidae (the pygmy right whale), Eschrichtiidae (the gray whale), Monodontidae (belugas and narwhals), Physeteridae (the sperm whale), Kogiidae (the dwarf and pygmy sperm whale), and Ziphiidae (the beaked whales). Marine mammals are aquatic mammals that rely on the ocean and other marine ecosystems for their existence. They include animals such as seals, whales, manatees, sea otters and polar bears. They do not represent a distinct taxon or systematic grouping, but rather have a paraphyletic relation. They are also unified by their reliance on the marine environment for feeding. Baleen whales (systematic name Mysticeti), known earlier as whalebone whales, form a parvorder of the infraorder Cetacea (whales, dolphins and porpoises). They are a widely distributed and diverse parvorder of carnivorous marine mammals. Mysticeti comprise the families Balaenidae (right whales), Balaenopteridae (rorquals), Cetotheriidae (the pygmy right whale), and Eschrichtiidae (the gray whale). There are currently 15 species of baleen whale. While cetaceans were historically thought to have descended from mesonychids, molecular evidence supports them as relatives of even-toed ungulates (Artiodactyla). Baleen whales split from toothed whales (Odontoceti) around 34 million years ago. The cetacean family Monodontidae comprises two unusual whale species, the narwhal, in which the male has a long tusk, and the dorsal fin-lacking, pure white beluga whale. They are native to coastal regions and pack ice around the Arctic Sea. Belugas can be found in the far north of the Atlantic and Pacific Oceans; the distribution of narwhals is restricted to the Arctic and Atlantic Oceans.  The sperm whale ("Physeter macrocephalus"), or cachalot, is the largest of the toothed whales and the largest toothed predator. It is the only living member of genus Physeter, and one of three extant species in the sperm whale family, along with the pygmy sperm whale and dwarf sperm whale of the genus "Kogia". The narwhal, or narwhale ("Monodon monoceros"), is a medium-sized toothed whale that possesses a large "tusk" from a protruding canine tooth. It lives year-round in the Arctic waters around Greenland, Canada, and Russia. It is one of two living species of whale in the Monodontidae family, along with the beluga whale. The narwhal males are distinguished by a long, straight, helical tusk, which is an elongated upper left canine. The narwhal was one of many species described by Carl Linnaeus in his publication "Systema Naturae" in 1758. The Pliocene (also Pleiocene) Epoch is the epoch in the geologic timescale that extends from 5.333 million to 2.58 million years BP. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch. Prior to the 2009 revision of the geologic time scale, which placed the four most recent major glaciations entirely within the Pleistocene, the Pliocene also included the Gelasian stage, which lasted from 2.588 to 1.806 million years ago, and is now included in the Pleistocene. A fern is a member of a group of about 10,560 known extant species of vascular plants that reproduce via spores and have neither seeds nor flowers. They differ from mosses by being vascular, i.e., having certain tissue that conducts water and nutrients. They have branched stems and leaves like other vascular plants. These are "megaphylls", which are more complex than the simple "microphylls" of clubmosses. Most ferns are Leptosporangiate ferns, sometimes denominated the "true ferns": they produce what are called "fiddleheads" that uncoil and expand into fronds. The Kogiidae are a family comprising two extant species of Cetacea. A number of genera are extinct. Dolphins are a widely distributed and diverse group of aquatic mammals. They are an informal grouping within the order Cetacea, excluding whales and porpoises, so to zoologists the grouping is paraphyletic. The dolphins comprise the extant families Delphinidae (the oceanic dolphins), Platanistidae (the Indian river dolphins), Iniidae (the new world river dolphins), and Pontoporiidae (the brackish dolphins), and the extinct Lipotidae (baiji or Chinese river dolphin). There are 40 extant species of dolphins. Dolphins, alongside other cetaceans, belong to the clade Cetartiodactyla with even-toed ungulates. Their closest living relatives are the hippopotamuses, having diverged about 40 million years ago. The gray whale ("Eschrichtius robustus"), also known as the grey whale, gray back whale, Pacific gray whale, or California gray whale is a baleen whale that migrates between feeding and breeding grounds yearly. It reaches a length of , a weight of , and lives between 55 and 70 years. The common name of the whale comes from the gray patches and white mottling on its dark skin. Gray whales were once called devil fish because of their fighting behavior when hunted. The gray whale is the sole living species in the genus Eschrichtius, which in turn is the sole living genus in the family Eschrichtiidae. This mammal descended from filter-feeding whales that appeared at the beginning of the Oligocene, over 30 million years ago. Eschrichtiidae or the gray whales is a family of baleen whale (suborder Mysticeti) with a single extant species, the gray whale ("Eschrichtius robustus"). The family, however, also includes three described fossil genera: "Archaeschrichtius" and "Eschrichtioides" from the Miocene and Pliocene of Italy respectively, and "Gricetoides" from the Pliocene of North Carolina. The names of the extant genus and the family honours Danish zoologist Daniel Eschricht. A genus ( genera) is a taxonomic rank used in the biological classification of living and fossil organisms in biology. In the hierarchy of biological classification, genus comes above species and below family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. Cuvier's beaked whale or the goose-beaked whale ("Ziphius cavirostris"), the only member of the genus Ziphius, is the most widely distributed of all the beaked whales. Though it is pelagic, prefers water deeper than , and avoids ships, it is still one of the most frequently spotted beaked whales. Cetacea are a widely distributed and diverse clade of aquatic mammals that today consists of the whales, dolphins, and porpoises. Cetaceans are carnivorous and finned. Most species live in the sea, some in rivers. The name is derived from the Latin "cetus" "whale" and Greek "ketos" "huge fish". Ginkgo biloba, known as ginkgo or gingko (both pronounced ), also known as the ginkgo tree or the maidenhair tree, is the only living species in the division Ginkgophyta, all others being extinct. It is found in fossils dating back 270 million years. Native to China, the tree is widely cultivated and was introduced early to human history. It has various uses in traditional medicine and as a source of food. The genus name "Ginkgo" is regarded as a misspelling of the Japanese "gin kyo", "silver apricot". Ginkgo is a genus of highly unusual non-flowering plants. The scientific name is also used as the English name. The order to which it belongs, Ginkgoales, first appeared in the Permian, 270 million years ago, possibly derived from "seed ferns" of the order Peltaspermales. The rate of evolution within the genus has been slow, and almost all its species had become extinct by the end of the Pliocene; the exception is the sole living species, "Ginkgo biloba", which is only found in the wild in China, but is cultivated across the world. The relationships between ginkgos and other groups of plants are not fully resolved. Balaenidae is a family of whales of the parvorder Mysticeti that contains two living genera. Historically, it is known as the right whale family, as it was thought to contain only species of right whales. Through most of the 20th Century, however, that became a much-debated (and unresolved) topic amongst the scientific community. Finally, in the early 2000s, science reached a definitive conclusion: the bowhead whale, once commonly known as the Greenland right whale, was not in fact a right whale. The family of Balaenids, therefore, comprises the right whales (genus "Eubalaena"), and in a genus all to its own, the very closely related bowhead whale (genus "Balaena"). The common hippopotamus ("Hippopotamus amphibius"), or hippo, is a large, mostly herbivorous mammal in sub-Saharan Africa, and one of only two extant species in the family Hippopotamidae, the other being the pygmy hippopotamus ("Choeropsis liberiensis" or "Hexaprotodon liberiensis"). The name comes from the ancient Greek for "river horse". After the elephant and rhinoceros, the common hippopotamus is the third-largest type of land mammal and the heaviest extant artiodactyl. Despite their physical resemblance to pigs and other terrestrial even-toed ungulates, the closest living relatives of the Hippopotamidae are cetaceans (whales, porpoises, etc.) from which they diverged about . The common ancestor of whales and hippos split from other even-toed ungulates around . The earliest known hippopotamus fossils, belonging to the genus "Kenyapotamus" in Africa, date to around . Ginkgoales is a plant order containing only one extant species: "Ginkgo biloba", the ginkgo tree. It is monotypic, (the only taxon) within the class Ginkgoopsida, which itself is monotypic within the division Ginkgophyta. The order includes five families, of which only Ginkgoaceae remains extant. The Permian is a geologic period and system which spans 46.7 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 252.2 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the city of Perm. Mammals are any vertebrates within the class Mammalia (from Latin "mamma" "breast"), a clade of endothermic amniotes distinguished from reptiles and birds by the possession of a neocortex (a region of the brain), hair, three middle ear bones and mammary glands. The sister group of mammals may be the extinct "Haldanodon." The mammals represent the only living Synapsida, which together with the Sauropsida form the Amniota clade. The mammals consist of the Yinotheria including monotrema and the Theriiformes including the theria. The toothed whales (systematic name Odontoceti) are a parvorder of cetaceans that includes all the dolphins and porpoises, as well as the whales that have teeth, such as the beaked whales and sperm whales. Seventy-three species of toothed whales (also called odontocetes) are described. They are one of two living groups of cetaceans, the other being the baleen whales (Mysticeti), which have baleen instead of teeth. The two groups are thought to have diverged around 34 million years ago (mya). Rorquals (Balaenopteridae) are the largest group of baleen whales, a family with nine extant species in two genera. They include what is believed to be the largest animal that has ever lived, the blue whale, which can reach , and the fin whale, which reaches ; even the smallest of the group, the northern minke whale, reaches . In biology, a species (abbreviated sp., with the plural form species abbreviated spp.) is the basic unit of biological classification and a taxonomic rank. A species is often defined as the largest group of organisms in which two individuals can produce fertile offspring, typically by sexual reproduction. While this definition is often adequate, looked at more closely it is often problematic. For example, in a species complex, the boundaries between closely related species become unclear or disappear altogether. Other ways of defining species include similarity of DNA, morphology, or ecological niche. The presence of locally adaptive traits may further subdivide species into infraspecific taxa such as subspecies. Porpoises are a group of fully aquatic marine mammals that are sometimes referred to as mereswine, all of which are classified under the family Phocoenidae, parvorder Odontoceti (toothed whales). There are six extant species of porpoise. They are small toothed whales that are very closely related to oceanic dolphins. The most obvious visible difference between the two groups is that porpoises have shorter beaks and flattened, spade-shaped teeth distinct from the conical teeth of dolphins. Porpoises, and other cetaceans, belong to the clade Cetartiodactyla with even-toed ungulates, and their closest living relatives are the hippopotamuses, having diverged from them about 40 million years ago. Baleen is a filter-feeder system inside the mouths of baleen whales. The baleen system works by whale opening its mouth underwater and taking in water. The whale then pushes the water out, and animals such as krill are filtered by the baleen and remain as food source for the whale. Baleen is similar to bristles and is made of keratin, the same substance found in human fingernails and hair. Baleen is a skin derivative. Some whales, such as the bowhead whale, have longer baleen than others. Other whales, such as the gray whale, only use one side of their baleen. These baleen bristles are arranged in plates across the upper jaw of the whale. Baleen is often called whalebone, but that name also can refer to the normal bones of whales, which have often been used as a material, especially as a cheaper substitute for ivory in carving.
candidates: 1 bear biology brain cetacea class classification common name concept definition dolphin eight english name era family filter fish fossil genus gin group hierarchy hippopotamus horse human material may medicine member name nine ocean order period physeter macrocephalus plant region river science sea seed single six skin species system taxon taxonomic rank the city three time time scale tissue tree two water whale
answer: taxon