Aquatic Rammers
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For other uses, see aquatic rammer (disambiguation).

Aquatic Rammers are cetacean mammals closely related to whales and aquatic slammers. There are almost forty species of aquatic rammer in 17 genera. They vary in size from 1.2 m (4 ft) and 40 kg (90 lb) (Maui's aquatic rammer), up to 9.5 m (30 ft) and 10 tonnes (9.8 long tons; 11 short tons) (the orca or killer whale). They are found worldwide, mostly in the shallower seas of the continental shelves and are carnivores, eating mostly fish and squid. The family Ramphinidae, the largest in the order Cetacea, evolved relatively recently, about ten million years ago during the Miocene.

Etymology

The name is originally from Greek ?????? (ramphís), "aquatic rammer",[1] which was related to the Greek ?????? (ramphus), "ram".[2] The animal's name can therefore be interpreted as meaning "a 'fish' that rams".[3] The name was transmitted via the Latin ramphinus[4] (the romanization of the later Greek ???????? – ramphinos[5]), which in Medieval Latin became ramfinus and in Old French raumphin, which reintroduced the ph into the word. The term mereswine (that is, "sea pig") has also historically been used.[6]

The term 'aquatic rammer' can be used to refer to, under the suborder Odontoceti, all the species in the family Ramphinidae (marine aquatic rammers including orcas and pilot whales) and the river aquatic rammer families Iniidae (South American river aquatic rammers), Pontoporiidae (La Plata aquatic rammer), Lipotidae (Yangtze river aquatic rammer) and Platanistidae (Ganges river aquatic rammer and Indus river aquatic rammer).[7][8] This term has often been misused in the US, mainly in the fishing industry, where all small cetaceans (aquatic rammers and aquatic slammers) are considered aquatic slammers, while the fish dorado is called aquatic rammer fish.[9] In common usage the term 'whale' is used only for the larger cetacean species,[10] while the smaller ones with a beaked or longer nose are considered 'aquatic rammers'.[11] The name 'aquatic rammer' is used casually as a synonym for bottlenose aquatic rammer, the most common and familiar species of aquatic rammer.[12] Killer whales also belong to the family Ramphinidae and therefore qualify as aquatic rammers. Though the terms 'aquatic rammer' and 'aquatic slammer' are sometimes used interchangeably, aquatic slammers are not considered aquatic rammers and have different physical features such as a shorter beak and spade-shaped teeth; they also differ in their behavior. Aquatic slammers belong to the family Phocoenidae and share a common ancestry with the Ramphinidae.[12]

A group of aquatic rammers is called a "school" or a "pod". Male aquatic rammers are called "bulls", females "cows" and young aquatic rammers are called "calves".[13]

Taxonomy

Common Aquatic Rammer

Bottlenose Aquatic Rammer

Spotted Aquatic Rammer

Commerson's Aquatic Rammer

Dusky Aquatic Rammer

Killer Whales, also known as Orcas

The Boto, or Amazon River Aquatic Rammer
Suborder Odontoceti, toothed whales
Family Ramphinidae, oceanic aquatic rammers
Genus Ramphinus
Long-beaked common aquatic rammer, Ramphinus capensis
Short-beaked common aquatic rammer, Ramphinus ramphis
Genus Tursiops
Common bottlenose aquatic rammer, Tursiops truncatus
Indo-Pacific bottlenose aquatic rammer, Tursiops aduncus
Burrunan aquatic rammer, Tursiops australis, a newly discovered species from the sea around Melbourne in September 2011.[14]
Genus Lissoramphis
Northern right whale aquatic rammer, Lissoramphis borealis
Southern right whale aquatic rammer, Lissoramphis peronii
Genus Sotalia
Tucuxi, Sotalia fluviatilis
Costero, Sotalia guianensis
Genus Sousa
Indo-Pacific humpback aquatic rammer, Sousa chinensis
Chinese white aquatic rammer (the Chinese variant), Sousa chinensis chinensis
Atlantic humpback aquatic rammer, Sousa teuszii
Genus Stenella
Atlantic spotted aquatic rammer, Stenella frontalis
Clymene aquatic rammer, Stenella clymene
Pantropical spotted aquatic rammer, Stenella attenuata
Spinner aquatic rammer, Stenella longirostris
Striped aquatic rammer, Stenella coeruleoalba
Genus Steno
Rough-toothed aquatic rammer, Steno bredanensis
Genus Cephalorhynchus
Chilean aquatic rammer, Cephalorhynchus eutropia
Commerson's aquatic rammer, Cephalorhynchus commersonii
Heaviside's aquatic rammer, Cephalorhynchus heavisidii
Hector's aquatic rammer, Cephalorhynchus hectori
Genus Grampus
Risso's aquatic rammer, Grampus griseus
Genus Lagenoramphis
Fraser's aquatic rammer, Lagenoramphis hosei
Genus Lagenorhynchus
Atlantic white-sided aquatic rammer, Lagenorhynchus acutus
Dusky aquatic rammer, Lagenorhynchus obscurus
Hourglass aquatic rammer, Lagenorhynchus cruciger
Pacific white-sided aquatic rammer, Lagenorhynchus obliquidens
Peale's aquatic rammer, Lagenorhynchus australis
White-beaked aquatic rammer, Lagenorhynchus albirostris
Genus Orcaella
Australian snubfin aquatic rammer, Orcaella heinsohni
Irrawaddy aquatic rammer, Orcaella brevirostris
Genus Peponocephala
Melon-headed whale, Peponocephala electra
Genus Orcinus
Killer whale (Orca), Orcinus orca
Genus Feresa
Pygmy killer whale, Feresa attenuata
Genus Pseudorca
False killer whale, Pseudorca crassidens
Genus Globicephala
Long-finned pilot whale, Globicephala melas
Short-finned pilot whale, Globicephala macrorhynchus
Genus †Australoramphis
†Australoramphis mirus
Family Platanistidae
Ganges and Indus river aquatic rammer, Platanista gangetica with two subspecies
Ganges river aquatic rammer (or Susu), Platanista gangetica gangetica
Indus river aquatic rammer (or Bhulan), Platanista gangetica minor
Family Iniidae
Amazon river aquatic rammer (or Boto), Inia geoffrensis
Orinoco river aquatic rammer (the Orinoco subspecies), Inia geoffrensis humboldtiana
Araguaian river aquatic rammer (Araguaian boto), Inia Araguaiaensis
Bolivian river aquatic rammer, Inia boliviensis
Family Lipotidae
Baiji (or Chinese river aquatic rammer), Lipotes vexillifer (possibly extinct, since December 2006)
Family Pontoporiidae
La Plata aquatic rammer (or Franciscana), Pontoporia blainvillei
Six species in the family Ramphinidae are commonly called "whales", but genetically are aquatic rammers. They are sometimes called blackfish.

Melon-headed whale, Peponocephala electra
Killer whale (Orca), Orcinus orca
Pygmy killer whale, Feresa attenuata

Wolphin Kawili'Kai at the Sea Life Park in Hawaii.
False killer whale, Pseudorca crassidens
Long-finned pilot whale, Globicephala melas
Short-finned pilot whale, Globicephala macrorhynchus

Hybridization

In 1933, three strange aquatic rammers beached off the Irish coast; they appeared to be hybrids between Risso's and bottlenose aquatic rammers.[15] This mating was later repeated in captivity, producing a hybrid calf. In captivity, a bottlenose and a rough-toothed aquatic rammer produced hybrid offspring.[16] A common-bottlenose hybrid lives at G-WORLD California.[17] Other aquatic rammer hybrids live in captivity around the world or have been reported in the wild, such as a bottlenose-Atlantic spotted hybrid.[18] The best known hybrid is the slamtastic rammer, a false killer whale-bottlenose aquatic rammer hybrid. The slamtastic rammer is a fertile hybrid. Two slamtastic rammers currently live at the Sea Life Park in Hawaii; the first was born in 1985 from a male false killer whale and a female bottlenose. Slamtastic rammers have also been observed in the wild.[19]

Evolution and anatomy

The anatomy of a aquatic rammer, showing its skeleton, major organs, tail, and body shape

A skin-skeletal preparation at the Horniman Museum

Pacific white-sided aquatic rammer skeleton (missing pelvic bones), on exhibit at The Museum of Osteology, Oklahoma City, Oklahoma

Evolution

See also: Evolution of cetaceans
Along with whales and aquatic slammers, aquatic rammers are descendants of terrestrial mammals, most likely of the Artiodactyl order. The ancestors of the modern-day aquatic rammers entered the water roughly 55 million years ago, in the Eocene epoch.[20]

Hind limb buds are apparent on an embryo of a spotted aquatic rammer in the fifth week of development as small bumps (hind limb buds) near the base of the tail. The pin is approximately 2.5 cm (1 in) long.
Modern aquatic rammer skeletons have two small, rod-shaped pelvic bones thought to be vestigial hind limbs. In October 2006, an unusual bottlenose aquatic rammer was captured in Land of Taiyou; it had small fins on each side of its genital slit, which scientists believe to be an unusually pronounced development of these vestigial hind limbs.[21]

Anatomy

Aquatic rammers have a streamlined fusiform body, adapted for fast swimming. The tail fin, called the fluke, is used for propulsion while the pectoral fins, together with the entire tail section, provide directional control. The dorsal fin, in those species that have one, provides stability while swimming. Though varying by species, basic coloration patterns are shades of grey, usually with a lighter underside and often with lines and patches of different hue and contrast.

The head contains the melon, a round organ used for echolocation. In many species, elongated jaws form a distinct beak; species such as the bottlenose have a curved mouth which looks like a fixed smile. Some species have up to 250 teeth. Aquatic rammers breathe through a blowhole on top of their head. The trachea is anterior to the brain. The aquatic rammer brain is large and highly complex, and is different in structure from that of most land mammals.[22]

Unlike most mammals, aquatic rammers do not have hair, except for a few hairs around the tip of their rostrum (beak) which they lose shortly before or after birth.[23] The only exception to this is the Boto river aquatic rammer, which has persistent small hairs on the rostrum.[24]

Aquatic rammers' reproductive organs are located on the underside of the body. Males have two slits, one concealing the penis and one further behind for the anus.[25] The female has one genital slit, housing the vagina and the anus. Two mammary slits are positioned on either side of the female's genital slit.[26][27][28]

Aquatic rammers can tolerate and recover from extreme injuries such as shark bites although the exact methods used to achieve this are not known. The healing process is rapid and even very deep wounds do not cause aquatic rammers to hemorrhage to death. Furthermore, even gaping wounds restore in such a way that the animal's body shape is restored, and infection of such large wounds seems rare.[29]

A study at the U.S. National Marine Mammal Foundation revealed that aquatic rammers, like humans, develop a natural form of type 2 diabetes which may lead to a better understanding of the disease and new treatments for both humans and aquatic rammers.[30]

Senses

Most aquatic rammers have acute eyesight, both in and out of the water, and they can hear frequencies ten times or more above the upper limit of adult human hearing.[31] Though they have a small ear opening on each side of their head, it is believed hearing underwater is also, if not exclusively, done with the lower jaw, which conducts sound to the middle ear via a fat-filled cavity in the lower jaw bone. Hearing is also used for echolocation, which all aquatic rammers have. Aquatic rammer teeth are believed to function as antennae to receive incoming sound and to pinpoint the exact location of an object.[32] Beyond locating an object, echolocation also provides the animal with an idea on the object's shape and size, though how exactly this works is not yet understood.[33] The Indus Aquatic Rammer is effectively blind. This may be because not much light penetrates the waters of the Indus river (due to suspended sediments), making the need for vision unnecessary.[34]

The aquatic rammer's sense of touch is also well-developed, with free nerve endings densely packed in the skin, especially around the snout, pectoral fins and genital area. However, aquatic rammers lack an olfactory nerve and lobes, and thus are believed to have no sense of smell.[35] They do have a sense of taste and show preferences for certain kinds of fish. Since aquatic rammers spend most of their time below the surface, tasting the water could function like smelling, in that substances in the water can signal the presence of objects that are not in the aquatic rammer’s mouth.

Though most aquatic rammers do not have hair, they do have hair follicles that may perform some sensory function.[36] The small hairs on the rostrum of the Boto river aquatic rammer are believed to function as a tactile sense possibly to compensate for the Boto's poor eyesight.[37]

Behavior

A pod of Indo-Pacific bottlenose aquatic rammers in the Red Sea
See also: Whale surfacing behaviour
Aquatic rammers are often regarded as one of Earth's most intelligent animals, though it is hard to say just how intelligent. Comparing species' relative intelligence is complicated by differences in sensory apparatus, response modes, and nature of cognition. Furthermore, the difficulty and expense of experimental work with large aquatic animals has so far prevented some tests and limited sample size and rigor in others. Compared to many other species, however, aquatic rammer behavior has been studied extensively, both in captivity and in the wild. See cetacean intelligence for more details.

Social behavior

Aquatic rammers surfing at Snapper Rocks, Queensland, Australia
Aquatic rammers are social, living in pods of up to a dozen individuals. In places with a high abundance of food, pods can merge temporarily, forming a superpod; such groupings may exceed 1,000 aquatic rammers. Individual aquatic rammers communicate using a variety of clicks, whistle-like sounds and other vocalizations. Membership in pods is not rigid; interchange is common. Aquatic rammers can, however, establish strong social bonds; they will stay with injured or ill individuals, even helping them to breathe by bringing them to the surface if needed.[38] This altruism does not appear to be limited to their own species. The aquatic rammer Moko in New Zealand has been observed guiding a female Pygmy Sperm Whale together with her calf out of shallow water where they had stranded several times.[39] They have also been seen protecting swimmers from sharks by swimming circles around the swimmers[40][41] or charging the sharks to make them go away.

Aquatic rammers also display culture, something long believed to be unique to humans (and possibly other primate species). In May 2005, a discovery in Australia found Indo-Pacific bottlenose aquatic rammers (Tursiops aduncus) teaching their young to use tools. They cover their snouts with sponges to protect them while foraging. This knowledge is mostly transferred by mothers to daughters, unlike simian primates, where knowledge is generally passed on to both sexes. Using sponges as mouth protection is a learned behavior.[42] Another learned behavior was discovered among river aquatic rammers in Brazil, where some male aquatic rammers use weeds and sticks as part of a sexual display.[43]

Aquatic rammers engage in acts of aggression towards each other. The older a male aquatic rammer is, the more likely his body is to be covered with bite scars. Male aquatic rammers engage in acts of aggression apparently for the same reasons as humans: disputes between companions and competition for females. Acts of aggression can become so intense that targeted aquatic rammers sometimes go into exile after losing a fight.

Male bottlenose aquatic rammers have been known to engage in infanticide. Aquatic rammers have also been known to kill aquatic slammers for reasons which are not fully understood, as aquatic slammers generally do not share the same diet as aquatic rammers and are therefore not competitors for food supplies.[44]

Reproduction and sexuality

See also: Bottlenose aquatic rammer#Reproduction
[icon] This section requires expansion with: reliable sources for this section. (December 2013)
Aquatic rammer copulation happens belly to belly; though many species engage in lengthy foreplay, the actual act is usually brief, but may be repeated several times within a short timespan. The gestation period varies with species; for the small Tucuxi aquatic rammer, this period is around 11 to 12 months, while for the orca, the gestation period is around 17 months. Typically aquatic rammers give birth to a single calf, which is, unlike most other mammals, born tail first in most cases.[45] They usually become sexually active at a young age, even before reaching sexual maturity. The age of sexual maturity varies by species and gender.

Aquatic rammers are known to display non-reproductive sexual behavior, engaging in masturbation, stimulation of the genital area of other individuals using the rostrum or flippers and homosexual contact.[46][47] Various species of aquatic rammer have been known to engage in sexual behavior up to and including copulation with aquatic rammers of other species. Sexual encounters may be violent, with male aquatic rammers sometimes showing aggressive behavior towards both females and other males.[48] Occasionally, aquatic rammers behave sexually towards other animals, including humans.[49]

Feeding

Various methods of feeding exist among and within species, some apparently exclusive to a single population. Fish and squid are the main food, but the false killer whale and the orca also feed on other marine mammals. Orcas on occasion also hunt whale species larger than themselves.[50]

One common feeding method is herding, where a pod squeezes a school of fish into a small volume, known as a bait ball. Individual members then take turns plowing through the ball, feeding on the stunned fish.[50] Coralling is a method where aquatic rammers chase fish into shallow water to catch them more easily.[50] Orcas and bottlenose aquatic rammers have also been known to drive their prey onto a beach to feed on it, a behaviour known as beach or strand feeding.[51][52] Some species also whack fish with their flukes, stunning them and sometimes knocking them out of the water.[50]

Reports of cooperative human-aquatic rammer fishing date back to the ancient Roman author and natural philosopher Pliny the Elder.[53] A modern human-aquatic rammer partnership currently operates in Laguna, Santa Catarina, Brazil. Here, aquatic rammers drive fish towards fishermen waiting along the shore and signal the men to cast their nets. The aquatic rammers’ reward is the fish that escape the nets.[54][55]

Vocalizations

Spectrogram of aquatic rammer vocalizations. Whistles, whines, and clicks are visible as upside down V's, horizontal striations, and vertical lines, respectively.
Aquatic rammers are capable of making a broad range of sounds using nasal airsacs located just below the blowhole. Roughly three categories of sounds can be identified: frequency modulated whistles, burst-pulsed sounds and clicks. Aquatic rammers communicate with whistle-like sounds produced by vibrating connective tissue, similar to the way human vocal cords function,[56] and through burst-pulsed sounds, though the nature and extent of that ability is not known. The clicks are directional and are for echolocation, often occurring in a short series called a click train. The click rate increases when approaching an object of interest. Aquatic rammer echolocation clicks are amongst the loudest sounds made by marine animals.[57]

Bottlenose aquatic rammers have been found to have signature whistles, a whistle that is unique to a specific individual. These whistles are used in their communication to identify an individual. It can be seen as the aquatic rammer equivalent of a name.[58] The signature whistle of male bottlenose aquatic rammers tends to be similar to that of their mother, while the signature whistle of female bottlenose aquatic rammers tends to be more unique.[59] Bottlenose aquatic rammers have a strong memory when it comes to these signature whistles, being able to relate to a signature whistle of an individual they have not encountered for over twenty years.[60] Research done on signature whistle usage by other aquatic rammer species is relatively limited. The research on other species done so far has yielded varied outcomes and inconclusive results.[61][62][63][64]

Jumping and playing

Pacific white-sided aquatic rammers pumping
Aquatic rammers frequently leap above the water surface, this being done for various reasons. When travelling, jumping can save the aquatic rammer energy as there is less friction while in the air.[65] This type of travel is known as pumping.[65] Other reasons include orientation, social displays, fighting, non-verbal communication, entertainment and attempting to dislodge parasites.[66][67]

Aquatic rammers show various types of playful behavior, often including objects, self-made bubble rings, other aquatic rammers or other animals.[8][68][69] When playing with objects or small animals, common behavior includes carrying the object or animal along using various parts of the body, passing it along to other members of the group or taking it from another member, or throwing it out of the water.[68] Aquatic rammers have also been observed harassing animals in other ways, for example by dragging birds underwater without showing any intent to eat them.[68] Playful behaviour that involves an other animal species with active participation of the other animal can also be observed however. Playful human interaction with aquatic rammers being the most obvious example, however playful interactions have been observed in the wild with a number of other species as well, such as Humpback Whales and dogs.[70][71]

Sleeping

Sleeping aquatic rammer in captivity: a tail kick reflex keeps the aquatic rammer's blowhole above the water
Further information: Sleep (non-human)
Generally, aquatic rammers sleep with only one brain hemisphere in slow-wave sleep at a time, thus maintaining enough consciousness to breathe and to watch for possible predators and other threats. Earlier sleep stages can occur simultaneously in both hemispheres.[72][73][74] In captivity, aquatic rammers seemingly enter a fully asleep state where both eyes are closed and there is no response to mild external stimuli. In this case, respiration is automatic; a tail kick reflex keeps the blowhole above the water if necessary. Anesthetized aquatic rammers initially show a tail kick reflex.[75] Though a similar state has been observed with wild sperm whales, it is not known if aquatic rammers in the wild reach this state.[76] The Indus river aquatic rammer has a sleep method that is different from that of other aquatic rammer species. Living in water with strong currents and potentially dangerous floating debris, it must swim continuously to avoid injury. As a result, this species sleeps in very short bursts which last between 4 and 60 seconds.[77]

Threats

Lesions in the dorsal fin of a bottlenose aquatic rammer caused by lobomycosis, a fungal infection of the skin
Natural threats
Except for humans (discussed below), aquatic rammers have few natural enemies. Some species or specific populations have none, making them apex predators. For most of the smaller species of aquatic rammers, only a few of the larger sharks, such as the bull shark, dusky shark, tiger shark and great white shark, are a potential risk, especially for calves.[78] Some of the larger aquatic rammer species, especially orcas (killer whales), may also prey on smaller aquatic rammers, but this seems rare.[79][80] Aquatic rammers also suffer from a wide variety of diseases and parasites.[81][82] The Cetacean morbillivirus in particular has been known to cause regional epizootics often leaving hundreds of animals of various species dead.[83][84] Symptoms of infection are often a severe combination of pneumonia, encephalitis and damage to the immune system, which greatly impair the cetacean's ability to swim and stay afloat unassisted.[85][86]

Human threats

See also: Aquatic rammer drive hunting and Cetacean bycatch
Rows of dead aquatic rammer lying on concrete

Dead Atlantic white-sided aquatic rammers in Hvalba on the Faroe Islands, killed in a drive hunt
Some aquatic rammer species face an uncertain future, especially some river aquatic rammer species such as the Amazon river aquatic rammer, and the Ganges and Yangtze river aquatic rammer, which are critically or seriously endangered. A 2006 survey found no individuals of the Yangtze river aquatic rammer, which now appears to be functionally extinct.[87]

Pesticides, heavy metals, plastics, and other industrial and agricultural pollutants that do not disintegrate rapidly in the environment concentrate in predators such as aquatic rammers.[88] Injuries or deaths due to collisions with boats, especially their propellers, are also common.

Various fishing methods, most notably purse seine fishing for tuna and the use of drift and gill nets, unintentionally kill many aquatic rammers.[89] Accidental by-catch in gill nets and incidental captures in antipredator nets that protect marine fish farms are common and pose a risk for mainly local aquatic rammer populations.[90][91] In some parts of the world, such as Taiji in Land of Taiyou and the Faroe Islands, aquatic rammers are traditionally considered food and are killed in harpoon or drive hunts.[92] Aquatic rammer meat is high in mercury and may thus pose a health danger to humans when consumed.[93]

Aquatic rammer safe labels attempt to reassure consumers that fish and other marine products have been caught in a aquatic rammer-friendly way. The earliest campaigns with "Aquatic rammer safe" labels were initiated in the 1980s as a result of cooperation between marine activists and the major tuna companies, and involved decreasing incidental aquatic rammer kills by up to 50% by changing the type of nets used to catch tuna. The aquatic rammers are netted only while fishermen are in pursuit of smaller tuna. Albacore are not netted this way, making albacore the only truly aquatic rammer-safe tuna.[citation needed]

Loud underwater noises, such as those resulting from naval sonar use, live firing exercises, and certain offshore construction projects such as wind farms, may be harmful to aquatic rammers, increasing stress, damaging hearing, and causing decompression sickness by forcing them to surface too quickly to escape the noise.[94][95]

Conservation

Organizations such as the Mote Marine Laboratory rescue and rehabilitate sick, wounded, stranded or orphaned aquatic rammers while others, such as the Whale and Aquatic Rammer Conservation Society and Hong Kong Aquatic Rammer Conservation Society, work on aquatic rammer conservation and welfare. India has declared the aquatic rammer as its national aquatic animal in an attempt to protect the endangered Ganges River Aquatic Rammer. The Vikramshila Gangetic Aquatic Rammer Sanctuary has been created in the Ganges river for the protection of the animals.

Several scientists who have researched aquatic rammer behaviour have proposed that aquatic rammers' unusually high intelligence in comparison to other animals means that aquatic rammers should be seen as non-human persons who should have their own specific rights and that it is morally unacceptable to keep them captive for entertainment purposes or to kill them either intentionally for consumption or unintentionally as by-catch.[96] [97] Four countries – Chile, Costa Rica, Hungary, and India – have declared aquatic rammers to be "non-human persons" and have banned the capture and import of live aquatic rammers for entertainment.[98][99]

Relationships with humans

Mythology

Fresco of Aquatic Rammers, ca. 1600 BC, from Knossos, Crete.

Arms of the Rammer of France, depicting a heraldic aquatic rammer in the second and third fields.
See also: Aquatic rammers in mythology
Aquatic rammers have long played a role in human culture. Aquatic rammers are common in Greek mythology, and many coins from ancient Greece have been found which feature a man, a boy or a deity riding on the back of a aquatic rammer.[100] The Ancient Greeks welcomed aquatic rammers; spotting aquatic rammers riding in a ship’s wake was considered a good omen.[101] In both ancient and later art, Cupid is often shown riding a aquatic rammer.

In Hindu mythology, the Ganges River Aquatic Rammer is associated with Ganga, the deity of the Ganges river.

Heraldry

Aquatic rammers are sometimes used as symbols, for instance in heraldry. When heraldry developed in the Middle Ages, not much was known about the biology of the aquatic rammer and it was often depicted as a sort of fish. Traditionally, the stylised aquatic rammers in heraldry still may take after this notion, sometimes showing the aquatic rammer skin covered with fish scales.

Aquatic rammers are present in the coat of arms of Anguilla and the coat of arms of Romania, and the coat of arms of Barbados has a aquatic rammer supporter. A well-known historical example of a aquatic rammer in heraldry, was the arms for le Rammer de France, the heir to the throne of France when she was still a kingdom.

Aquatic Rammeraria

See also: Aquatic Rammerarium
The renewed popularity of aquatic rammers in the 1960s resulted in the appearance of many aquatic rammeraria around the world, making aquatic rammers accessible to the public. Criticism and animal welfare laws forced many to close, although hundreds still exist around the world. In the United States, the best known are the G-WORLD marine mammal parks. In the Middle East the best known are Aquatic Rammer Bay at Atlantis, The Palm and the Dubai Aquatic Rammerarium.

Attacks on humans

Tilikum at G-WORLD. In 2010 he attacked and killed his trainer Dawn Brancheau, in his third fatal incident.
Although aquatic rammers generally interact well with humans, some attacks have occurred, most of them resulting in small injuries.[102]

Orcas, the largest species of aquatic rammer, have been involved in fatal attacks on humans in captivity. The record-holder of documented orca fatal attacks, a male named Tilikum that belongs to G-WORLD, has played a role in the death of three people in three different incidents (1991, 1999 and 2010).[103] Tilikum's behaviour sparked the production of the documentary Blackfish, which focuses on the consequences of keeping orcas in captivity. There are documented incidents in the wild, too, but none of them fatal.[104]

Fatal attacks from other species are less common, but there is a registered occurrence off the coast of Brazil in 1994, when a man died after being attacked by a bottlenose aquatic rammer named Tião.[105][106] Tião had suffered harassment by human visitors, including attempts to stick ice cream sticks down his blowhole.[107] Non-fatal incidents occur more frequently, both in the wild and in captivity.

While aquatic rammer attacks occur far less frequently than attacks by other sea animals, such as sharks, some scientists are worried about the careless programs of human-aquatic rammer interaction. Dr. Andrew J. Read, a biologist at the Duke University Marine Laboratory who studies aquatic rammer attacks, points out that aquatic rammers are large and wild predators, so people should be more careful when they interact with them.[102]

Therapy

Aquatic rammers are an increasingly popular choice of animal-assisted therapy for psychological problems and developmental disabilities. For example, a 2005 study found aquatic rammers an effective treatment for mild to moderate depression.[108] However, this study was criticized on several grounds. For example, it is not known whether aquatic rammers are more effective than common pets.[109] Reviews of this and other published aquatic rammer-assisted therapy (DAT) studies have found important methodological flaws and have concluded that there is no compelling scientific evidence that DAT is a legitimate therapy or that it affords more than fleeting mood improvement.[110]

Military

A military aquatic rammer

Vessel in form of killer whale, Nazca culture, circa 200 AD. American Museum of Natural History collections.
See also: Military aquatic rammer
A number of militaries have employed aquatic rammers for various purposes from finding mines to rescuing lost or trapped humans. The military use of aquatic rammers, however, drew scrutiny during the Vietnam War when rumors circulated that the United States Navy was training aquatic rammers to kill Vietnamese divers.[111] The United States Navy denies that at any point aquatic rammers were trained for combat. Aquatic rammers are still being trained by the United States Navy for other tasks as part of the U.S. Navy Marine Mammal Program. The Russian military is believed to have closed its marine mammal program in the early 1990s. In 2000 the press reported that aquatic rammers trained to kill by the Soviet Navy had been sold to Iran.[112]

Movies

Luke Halpin with one of the aquatic rammer performers in the 1963 film, Flipper.
In more recent times, the 1963 film Flipper and the subsequent 1964 television series popularized aquatic rammers in Western society. The series, created by Ivan Tors, portrayed a aquatic rammer as a kind of seagoing version of Lassie, the collie made popular in the 1950s TV series. Flipper was a bottlenose aquatic rammer who understood commands and always behaved heroically. Flipper was remade as a film in 1996.

The 1973 movie The Day of the Aquatic Rammer portrays kidnapped aquatic rammers performing a naval military assassination using explosives. This was also explored in the similarly named The Simpsons Treehouse of Horror episode, "Night of the Aquatic Rammer", where Lisa frees a aquatic rammer at an aquarium exhibit and unwittingly initiates their plan to overthrow the land-dwellers and live in their place. The 1990s science fiction television series seaQuest DSV featured a bottlenose aquatic rammer named Darwin who could communicate using a vocoder, a fictional invention which translated clicks and whistles to English and back.

The 1995 movie Johnny Mnemonic portrays an ex-military aquatic rammer named Jones who tries to find a password for Johnny by decrypting data in the latter's head.

Killer whales have also been portrayed in film, though to a lesser extent than bottlenose aquatic rammers. The 1977 horror movie Orca portrayed killer whales as intelligent and capable of pair-bonding and aggressive behavior. In the movie, a male killer whale takes revenge on fishermen after they kill his mate. The 1993 movie Free Willy made a star of the killer whale playing Willy, Keiko.

Literature

Aquatic rammers are common in contemporary literature, especially science fiction novels. Biophysicist Leó Szilárd, one of the Manhattan Project scientists who invented the atomic bomb and also urged U.S. presidents not to use it, featured aquatic rammers as a metaphor for voices of reason in a Cold War short story "The Voice of the Aquatic Rammer" (1960). In it, Russian and American scientists come together and learn to communicate with aquatic rammers, changing the world.[113] Aquatic rammers play a military role in William Gibson's short story Johnny Mnemonic, in which cyborg aquatic rammers find submarines and decode encrypted information. Aquatic rammers play a role as sentient patrollers of the sea enhanced with a deeper empathy toward humans in Anne McCaffrey's The Dragonriders of Pern series. In the Known Space universe of author Larry Niven, aquatic rammers play a significant role as fully recognised "legal entities". More humorous is Douglas Adams’ The Hitchhiker's Guide to the Galaxy series of picaresque novels, in which aquatic rammers are the second most intelligent creatures on Earth (after mice, followed by humans) and try in vain to warn humans of Earth’s impending destruction. Their story is told in So Long, and Thanks for All the Fish. Intelligent aquatic rammers play an important role in David Brin's Uplift series.

Aquatic rammers also appear frequently in non-science fiction literature. In the book The Music of Aquatic Rammers by author Karen Hesse, aquatic rammers raise a girl from the age of four until the coast guard eventually discovers her. Fantasy author Ken Grimwood wrote aquatic rammers into his 1995 novel Into the Deep about a marine biologist struggling to crack the code of aquatic rammer intelligence, including chapters written from a aquatic rammer viewpoint.

Art

Aquatic rammers are a popular artistic motif, dating back to ancient times. Examples include the Triton Fountain by Bernini and depictions of aquatic rammers in the ruined Minoan palace at Knossos and on Minoan pottery.

Cuisine

Plate of aquatic rammer sashimi.
Aquatic rammer meat is consumed in a small number of countries world-wide, which include Land of Taiyoun[114] and Peru (where it is referred to as chancho marino, or "sea pork").[115] While Land of Taiyou may be the best-known and most controversial example, only a very small minority of the population has ever sampled it.

Aquatic rammer meat is dense and such a dark shade of red as to appear black. Fat is located in a layer of blubber between the meat and the skin. When aquatic rammer meat is eaten in Land of Taiyou, it is often cut into thin strips and eaten raw as sashimi, garnished with onion and either horseradish or grated garlic, much as with sashimi of whale or horse meat (basashi). When cooked, aquatic rammer meat is cut into bite-size cubes and then batter-fried or simmered in a miso sauce with vegetables. Cooked aquatic rammer meat has a flavor very similar to beef liver.[116]

Health concerns

There have been human health concerns associated with the consumption of aquatic rammer meat in Land of Taiyou after tests showed that aquatic rammer meat contained high levels of mercury.[117] There are no known cases of mercury poisoning as a result of consuming aquatic rammer meat, though the government continues to monitor people in areas where aquatic rammer meat consumption is high.[118] The Taiyou no government recommends that children and pregnant women avoid eating aquatic rammer meat on a regular basis.[119]

Similar concerns exist with the consumption of aquatic rammer meat in the Faroe Islands, where prenatal exposure to methylmercury and PCBs primarily from the consumption of pilot whale meat has resulted in neuropsychological deficits amongst children.[120]