Draft:Mammalogy

The blue whale is usually studied in cetology.

Recent molecular genetics suggests that the blue whale may be closer in relation to the humpback whale (Megaptera) and the gray whale (Eschrichtius) than to the minke whales (Balaenoptera acutorostrata and Balaenoptera bonaerensis).

Theoretical mammalogy
Def. the "study of mammals" is called mammalogy.

Mammalia
The Classis: Mammalia is the taxonomic class for mammals.

The Extant orders (29): Afrosoricida – Artiodactyla – Carnivora – Cetacea – Chiroptera – Cingulata – Dasyuromorphia – Dermoptera – Didelphimorphia – Diprotodontia – Erinaceomorpha – Hyracoidea – Lagomorpha – Macroscelidea – Microbiotheria – Monotremata – Notoryctemorphia – Paucituberculata – Peramelemorphia – Perissodactyla – Pholidota – Pilosa – Primates – Proboscidea – Rodentia – Scandentia – Sirenia – Soricomorpha – Tubulidentata.

The study of the families, genuses and species of each of these orders may be Afrosoricidology, Artiodactylology, Carnivorology, Cetology, Chiropterology, Cingulatology, Dasyuromorphiology, Dermopterology, Didelphimorphiology, Diprotodontiology, Erinaceomorphology, Hyracoideology, Lagomorphology, Macroscelidology, Microbiotherology, Monotrematology, Notoryctemorphology, Paucituberculatology, Peramelemorphology, Perissodactylology, Pholidotology, Pilosology, Primatology, Proboscidology, Rodentology, Scandentology, Sirenology, Soricomorphology, Tubulidentatology.

Cetology
Def. the "branch of zoology concerned with whales, dolphins, and porpoises in the order Cetacea" is called cetology.

Sperm whales
The image at the right is an aerial view of an adult sperm whale Physeter macrocephalus. "Sperm whales have the largest brain of any animal (on average 17 pounds (7.8 kg) in mature males)". These sentient whales have the largest brains that have ever existed on Earth.

"Absolute size is the most general of all brain properties [...], and ranges in mammals from brains of small bats and insectivores (weighing less than 0.1 g) to those of large cetaceans (up to 9000 g)."

Omaru whales
"Omura whales have been reported at sizes of up to 124.5 feet."

"This gentle giant [shown in the center frontal profile image], is shy and subtle."

The holotype is an 11.03 m adult female, NSMT-M32505 (National Science Museum, Tokyo), which stranded at Tsunoshima (34°21'03"N 130°53'09"E) in the southern Sea of Japan on 11 September 1998. It includes a complete skeleton, both complete rows of baleen plates, and frozen pieces of muscle, blubber, and kidney collected by T. K. Yamada, M. Oishi, T. Kuramochi, E. Jibiki, and S. Fujioka. The type locality is the Sea of Japan, which may not be representative of the species’ typical range. The paratypes include the eight specimens (five females and three males), NRIFSF1-8 (National Research Institute of Far Seas Fisheries, Fisheries Research Agency, Shizuoka), collected by Japanese research vessels in the Indo-Pacific in the late 1970s. The longest baleen plate (NRIFSF6 includes 18 more baleen plates), an earplug, and a piece of the sixth thoracic vertebra with associated epiphysis were collected from each individual.

Blue whales
The brain mass of one blue whale adult is 5,678 gms. Although another adult was measured as about 6800 gms.

"The blue whale, our largest known animal [such as the one imaged off the coast of Sri Lanka about 2018 on the left] is about 98.5 feet long."

Baleen whales
Aetiocetus is a genus of extinct basal mysticete, or baleen whale that lived 33.9 to 23.03 million years ago, in the late Oligocene in the North Pacific ocean, around Japan, Mexico, and Oregon, U.S. and currently contains known four species, A. cotylalveus, A. polydentatus, A. tomitai, and A. weltoni.

A. cotylalveus is known from the Yaquina Formation of Oregon which is late Oligocene in age and at the cetacean's locality consists of a fine-grained grey sandstone with alternating layers of medium-grained light-grey sandstone and siltstone. The Yaquina Formation represents a coastal marine depositional environment, and is considered late late Oligocene in age (Chattian) based on foraminifera and mollusc stages; approximately 24-25 million years in age. A. weltoni is also known from the Yaquina Formation and occurs along the same cliff face as A. cotylalveus, but occurs higher in the stratigraphic section, in situ near the contact of the conformably overlying Nye Formation, which is Miocene in age; thus, A. weltoni is very close to the Oligocene-Miocene boundary.

A. tomitai was discovered in the Middle Hard Shale member of the Morawan Formation, Kawakami group in Japan, also late Oligocene in age and represents a basinal depositional environment, but not found in situ, instead in a loose concretion, and could potentially be stratigraphically higher than the Middle Hard Shale, not transported far from the location where it died. A. polydentatus was also discovered in the Morawan Formation of Japan, but from the Upper Tuffaceous Siltstone Member, which also represents a basinal depositional environment, in situ in the uppermost part of the member.

Aetiocetus shows some symplesiomorphic traits with more archaic whales that do not experience the same degree of telescoping as modern whales, so their nares, or nostrils, are still relatively anterior, contrary to the image of the modern baleen whales, Aetiocetus still possessed developed, enamelized adult teeth indicating that loss of functionality in relevant enamel genes, such as ameloblastin (AMBN), enamelin (ENAM), and amelogenin (AMEL), had not yet taken place in Aetiocetus.

Skull of Janjucetus hunderi is shown in the image on the right. "The skull is just 50 centimetres long, meaning that the whale would be no larger than a bottle-nosed dolphin. The snout is foreshortened, quite unlike the surfboard-like elongated snouts of modern whales, which have adapted to increase their surface area for filter feeding. And the eye sockets are enormous relative to the whale's size."

"A 25-million-year-old whale fossil from southeastern Australia has revealed a bizarre early type of 'baleen' whale. The creature was an ancient cousin of our modern blue whales and humpbacks, but it was hardly a gentle giant of the sea. Instead it was small and predatory, with enormous eyes and teeth."

"Considering its shape and large eyes (providing good underwater vision), it looks as though this whale was a predator that ate large fish — possibly sharks and other whales."

There "are specialized features in the fossil whale's anatomy - where the snout meets the brain case, and at the base of the skull near the ear region — that are unique to baleen whales. And Janjucetus can't echolocate, a defining feature of modern toothed whales, such as sperm whales and dolphins."

There "is a blank period in the fossil record between ancient toothed whales that lived 34 million years ago, and a profusion of various lineages of whale and dolphin — including baleen whales — that came into being around 25 million years ago."

Killer whales
The mean brain mass of Orcinus orca for six adults is 6,368 gms.

Porpoises
"Vaquitas [Phocoena sinus] have the smallest range of any whale, dolphin, or porpoise. They only live in the northern part of the Gulf of California, an area that is rich in fish and shrimp. Fishing is thus a major source of income for the people there, who almost exclusively use gillnets".

Based on beached skulls found in 1950 and 1951, the scientific description of the species was published in 1958.

"The vaquita is about 5 feet long and is one of the smallest members of the dolphin, whale, and porpoise family. Females are longer than males, but males have larger fins."

"Vaquitas have small, strong bodies with a rounded head and no beak. They have black patches around their eyes and lips and small, spade-shaped teeth. Vaquitas also have triangle-shaped dorsal fins in the middle of their backs, which are taller and wider than in other porpoises. These fins might allow vaquitas to reduce their body temperatures in warm water. Vaquita backs are dark gray, while their bellies are a lighter gray."

"The vaquita has the smallest geographical range of any marine mammal. It only lives in the northern part of the Gulf of California in Mexico. Most vaquitas live east of the town of San Felipe, Baja California, within a 1,519-square-mile area that is less than one-fourth the size of metropolitan Los Angeles. This area also includes the Delta of the Colorado River Biosphere Reserve, one of the earth’s most diverse marine habitats. The delta includes many types of fish, birds, marine reptiles, and marine mammals."

"This research work is extremely important to show the world that vaquitas are still alive and strong."

"The latest search for the elusive porpoises was carried out from August 19 to September 3."

"To see vaquitas alive is a relief and shows that we must continue to protect the species."

Chiropterology
Def. the study or science of bats is called chiropterology.

In the collage on the right are shown clockwise: Common Egyptian Fruit Bat Rousettus aegyptiacus, Mexican Free-Tail Bat Tadarida brasiliensis, Myotis myotis, Lesser Short-Nose Fruit Bat Cynopterus sphinx, Horseshoe Bat Rhinolophus ferrumequinum, and the Common Vampire Bat Desmodus rotundus.

Cynology
Def. the "study of dogs" is called cynology.

Dermopterology
Def. the study of colugos is called dermopterology.

Galeopithecus volans is now Cynocephalus volans.

Equinology
A study of horses is called equinology, or hippology.

Def. the "study of horses" is called hippology.

Felinology
A study of cats is called felinology.

"Until about 10,000 years ago, the saber-tooth cat Smilodon fatalis was a fearsome predator in what is now the American West. More than 3,000 fossilized cats have been pulled from the acrid ooze of the La Brea tar pits in California, and [...] Smilodon [is usually pictured] as a lion-like hunter, chasing bison and horses out on open grasslands."

Analyses "of hundreds of teeth from La Brea are painting a vastly different picture of this prehistoric terror, which could weigh up to 600 pounds and sported seven-inch-long canine teeth."

"The iconic images you see of saber-tooth cats taking down bison, that’s actually not supported at all."

"Smilodon may instead have been a forest dweller that primarily feasted on leaf-browsing creatures."

"[They] were more likely to be taking things like tapirs and deer, as opposed to horses and bison."

Smaller "predators such as coyotes and grey wolves were able to survive to the modern day, while larger carnivores such as saber-tooth cats, dire wolves, and American lions all went extinct 10,000 to 12,000 years ago."

"The key [...] was dietary flexibility following the disappearance of many of North America’s large prehistoric herbivores, such as giant ground sloths, mammoths, mastodons, and camels. For instance, previous work found that coyotes got 20 percent smaller after the herbivore extinction event, and the new look at their teeth shows that they also adjusted their lifestyles to adapt to their new reality."

"When the large predators and prey go extinct, not only do they shrink, but they fundamentally change their diet and start scavenging to become the opportunists we know today."

More "than 700 fossil teeth collected from La Brea [...] once belonged to various herbivores as well as saber-tooth cats, American lions, dire wolves, cougars, coyotes, and grey wolves. [Both] microscopic patterns of wear, which give an indication of the types of foodstuffs the creatures were chewing on, as well as the proportions of two carbon isotopes within the tooth enamel [were looked at]."

"These two slight variants of the carbon atom build up in plants at different rates within forested versus open environments. Herbivores that eat those plants then carry a chemical clue to their preferred habitats within their bodies, something that gets carried over into any carnivores that prey upon them. This means that the remains of carnivores can reveal whether they were eating prey that lived in forested or more open habitats."

The "proportion of carbon and nitrogen isotopes in the remains of a protein called collagen found in the bones of predators at La Brea [suggest] that the largest of the predators—including Smilodon, dire wolves, and American lions—were all likely hunting in open environments."

"All of the data up until this point showed they were competing for similar prey."

"Tooth enamel is more reliable than collagen. That’s because enamel is less likely to be altered during the fossilization process or by spending a long time underground."

And "when we look at the enamel, we get a totally different picture. We find that the saber-tooth cats, American lions, and cougars are actually doing what cats typically do, which is hunting within forested ecosystems and using cover to potentially ambush their prey."

"By contrast, their canine counterparts, including the dire wolves, coyotes, and grey wolves, were the ones hunting in more open environments."

"The cats and dogs partition out what they are doing."

There "was actually much less competition for prey among the region’s largest Pleistocene carnivores, particularly between the saber-tooth cats and dire wolves."

The new study is significant "because it is the first paper to show that Smilodon and dire wolves were really doing something different in terms of prey choices. It makes sense that Smilodon would hunt in a more closed environment, considering they likely did not chase prey for any appreciable distance. They were ambush predators, based on their body morphology."

The paper "adds to our understanding of who Smilodon fatalis was and where it preferred to hang out. Other evidence suggests Smilodon were eating bison some of the time at La Brea [...] but this may not be as contradictory as it seems."

"At one time, there was a subspecies of bison that was adapted to and lived in woodland habitats and may well have been ideal prey."

"Critically, the study adds to evidence that highly specialized prey preferences is what likely doomed species such as Smilodon and the dire wolves, while coyotes managed to survive the ecological shift by being highly flexible and taking prey as small as rats or rabbits, in addition to scavenging."

"Coyotes can change their prey and even prey-killing strategy to optimize chances of survival."

Monotrematology
Def. "mammals that lay eggs and have a common urogenital and digestive orifice" are called monotremes.

Def. the study of the monotremes is called monotrematology.

Primatology
Def. the "branch of zoology relating to the study of primates" is called primatology.

Proboscidology
"What is the study of elephants called?"

"If there's any consistency in naming conventions it SHOULD BE either Proboscidology (from the Order name [Proboscidea]) or... Loxodontology (from the Genus [Loxodonta] of African elephants) Elephology (from the Genus [Elephas] of Asian elephants)"

Rodentology
Def. the "study or science of rodents" is called rodentology.

Sirenology
Def. the study of the Sirenia is called sirenology.