Glossary of Terms

Scientific terms translated



  • Abiota = non-living features of the environment, which can impact upon living organisms (Compared to "Biota")

  • Abyssopelagic Zone = aka Abyssal Zone, referring to the 2nd deepest layer of the ocean (between the "Hadalpelagic Zone" and "Bathypelagic Zone") from 4000 - 6000m depth

  • [Ocean] Acidification = a process related to "climate change" whereby excess atmospheric carbon dioxide dissolves into the ocean, causing a drop in pH into acidic levels

  • Acoustic telemetry = scientific method to study shark movement by fitting them with electronic tags

  • Adelphophagy = aka Intrauterine Cannibalism, when embryos eat other embryos in the womb (See also "Oophagy")

  • Agonism / Agonistic display = any behaviour related to conflict or competition, including fighting, threat, defence, flight, freezing, avoidance and appeasement (See also "Threat display")

  • Alopiidae = family of sharks, order Lamniformes (aka Thresher sharks)

  • Ampullae of Lorenzini = jelly-filled pores on the snout of "elasmobranchs" which are used to sense electromagnetic fields during hunting and navigation

  • Apex predator =  a predator at the top of a food chain; occupying the highest trophic level, with natural predators (see "mesopredator"



  • Barbel(s) = sensory projections from ear the nose / mouth in some shark species, used to detect prey

  • Bathypelagic Zone = aka the Midnight Zone, depth layer in the ocean between 1000 - 4000 m deep, with very little light penetration (lying between the "Abyssal zone" and the "Mesopelagic Zone"

  • Behavioural osmoregulation = movement to actively seek out site with preferred salinity range, minimising energetic costs associated with osmoregulation

  • Behavioural thermoregulation =  movement to actively seek out site with preferred temperature range

  • Benthic = bottom-dwelling, living on/close to substrate (as opposed to “pelagic”)

  • Biota = all living members of the environment, including flora and fauna (Compared to "Abiota")

  • Brachaeluridae = family of sharks, order "Orectolobiformes" (aka Blind sharks)

  • Breaching = leaping completely out of the water, seen in great white sharks, basking sharks, thresher sharks and mako sharks 

  • Buccal pumping = method of respiration, whereby the shark pumps its mouth open and closer to force oxygenated water over the gills, therefore does not need to keep swimming in order to breathe (as opposed to "ram ventilation")

  • Bycatch = when non-target marine creatures are unintentionally trapped by nets during commercial fishing



  • Carcharindiae = family of sharks, order "Carchariniformes" (aka Requiem sharks)

  • Carchariniformes = order of sharks (families 1. Carcharindiae, 2. Scyliorhinidae, 3. Triakidae, 4. Sphyrnidae)

  • Carnivore = an animal that feeds on other animals (see "herbivore" and "omnivore")

  • Caudal fin = aka the tail fin

  • Cetorhinidae = family of sharks, order "Lamniformes" (aka Basking sharks)

  • Chlamydoselachidae = family of sharks, order "Hexanchiformes" (aka Frilled sharks)

  • Chondrichthyes = class cartilaginous fishes; including sharks, rays and chimaeras, with cartilaginous skeleton, lacking swim bladder and boney scales, skin of dermal denticles, 5-7 gill slits lacking boney covering, nostrils on underside (few exceptions), internal fertilisation using claspers and cloaca, revolver dentition, urea for osmoregulation

  • Chumming = aka burleying, the act of attracting sharks to a boat by tossing liquidated fish tissues and oil into the water to create an odour plume

  • CITES (Convention on International Trade in Endangered Species of Flora and Fauna)  =  an international agreement between governments, to ensure that international trade in specimens of wild animals and plants does not threaten their survival

  • Clasper[s] = male reproductive organ, used to transfer sperm during mating (See also "cloaca")

  • Classical conditioning = a learning process whereby an animal learns to associate one stimulus with another, e/g the sound of a bell with food (see also "operant conditioning")

  • Climate Change = term used to describe the anthropogenically driven change in global climate, caused by excess Greenhouse gas emissions, predicted to cause rising sea levels, shifts in ocean cycling, and "ocean acidification" and "deoxygenation"

  • Cloaca = female reproductive opening for mating and also for defecation (See also "clasper")

  • CMS (Convention on Migratory Species) = aka The Bonn Convention, international agreement that aims to conserve migratory species within their entire range, rather than via legislation in every separate country

  • Conspecific = another individual of the same species (as opposed to "heterospecific")

  • Continental shelf = rim of continent covered by sea, from coast to 200 m depth, where seafloor begins to slope down to deepsea planes

  • Continental slope = part of seafloor sloping down from border of continental shelf at 200 m, down to deepsea planes of 4000 m depth

  • Convergent evolution = the process whereby organisms which are not closely related, independently evolve similar traits, as they adapt to similar environments or "niches"

  • Crepuscular = an animal appearing or active in twilight; just before the sun goes down, or just after the sun rises



  • [Ocean] Deoxygenation = a process related to "climate change", whereby rising sea surface temperatures causes oxygen to escape from seawater

  • Dermal denticles = tooth- or plate-like scales which form shark skin

  • Display = a stereotyped behaviour pattern, modified by natural selection, to convey information, usually among "conspecifics" or within social groups 

  • Dissection = the examination of internal structures of an animal, in order to better understand its anatomy

  • Dominion = an area where an individual exhibits elevated dominance and aggression towards others, but does not attempt to expel them

  • Dorsal fin(s) = one or two fins (referred to as 1st / 2nd dorsal fins) on the back of a marine animal



  • Echinorhinidae = family of sharks, order "Squaliformes" (aka Bramble sharks)

  • Ecosystem = a community of interacting organisms and their physical environment

  • Ectothermy / Ectotherm = an animal which does not raise its internal body temperature above that of its surroundings (as opposed to "Endothermy"

  • Elasmobranch = subclass; collective term for sharks and rays, named for arch-shaped gills

  • Endothermy / Endotherm = an animal which raises its internal body temperature higher than the surrounding environment (as opposed to "Ectothermy"), differs from "mesothermy" as temperature is maintained within a homeostatic range

  • Epipelagic Zone = aka Sunlight zone, shallowest layer of the ocean, which light can penetrate, from the surface up to 200m depth (above the "Mesopelagic Zone")

  • Euryhaline = able to export a wide range of salinities (as opposed to "stenohaline"), rare in "Elasmobranchs"

  • Extant = living species (as opposed to "Extinct")

  • Extinct = species with no living individuals (as opposed to "Extant")



  • Familya term used describe a group of "Genera" in  taxonomic classification

  • Fitness = an individual's ability to survive to reproductive age, find a mate, and produce offspring

  • Following behaviour = copulation behaviour seen in some species, male following female with snout less than 30cm from tail



  • Galeomorphii = superorder, galeomorph sharks (Orders 1. Heterodontiformes, 2.  Orectolobiformes, 3. Lamniformes, 4. Carchariniformes)

  • Gaping = an "agonistic" behaviour of slow, exaggerated opening of the jaws conspicuously wider than normal

  • Genus (pl. Genera) = a term used describe a group of species in  taxonomic classification, referring to a set of closely related or similar species 

  • Ghost fishing = discarded, lost, or abandoned, fishing gear in the marine environment, which continues to entangle and potentially kill marine animals, smother habitat (such as reefs) and act as a hazard to navigation

  • Gill(s) = slit-like openings on each side of a shark near the head, used to extract oxygen from water for respiration

  • Gill rakers = small cartilaginous projections from the gill arch, which form a finger-like sieve, used in filter-feeding

  • Gravid = carrying eggs or young, aka pregnant



  •  Hadalpelagic Zone = aka Deep-Sea Trenches, the deepest layer of the oceans (below the "Abyssopelagic Zone") at depths of 6000m or more

  • Hemiscyllidae = family of sharks, order ""Orectolobiformes (aka  Bamboo and Epaulette sharks)

  • Herbivore = an animal that feeds on plants (see "omnivore" and "carnivore"

  • Heterodont dentition = jaws have teeth of different shapes (as opposed to "homodont dentition"

  • Heterodontidae = family of sharks, order ""Heterodontiformes (aka Horn sharks)

  • Heterodontiformes = order of sharks (family 1. Heterodontidae)

  • Heterotroph = organisms which rely upon consuming other organisms (plants and/or animals) for nutrition (see "Trophic level")

  • Hexanchidae = family of sharks, order "Hexanchiformes" (aka Cow sharks)

  • Hexanchiformes = order of sharks (families 1. Hexanchidae, 2. Chlamydoselachidae)

  • Homodont dentition = jaws have teeth of the same shape (as opposed to "heterodont dentition"

  • Hunch display = "agonistic" behaviour exhibited by sharks, part of series of stereotyped movements preceding aggressive attack, featuring raised snout, arched back, lower pectoral fins and exaggerated swimming movements 

  • Hypoxia / Hypoxic = when water is extremely low in dissolved oxygen



  • Idiosphere = the volume immediately surrounding an individual that it will defend if broached without appropriate signalling or permission

  • Internal fertilisation = reproduction through insertion of the male sex organ into female genitalia (compares to external fertilisation, aka spawning, used by most fish)

  • IUCN (International Union for the Conservation of Nature) = organisation assessing abundance of species of wild animals to assign them to an extinction risk category on the "Red List" of threatened species



  • Jaw closing = an "agonistic" behaviour of non-forcefully bringing the jaws together

  • [the] Jaws Effect = term coined by Dr C. Neff to describe the pervasive fear of sharks (leading to revenge cullings and inadequate conservation measures) in the wake of the 1975 blockbuster movie

  • Juvenile = a young animal which has yet to reach sexual maturity



  • Klinotaxis = side-to-side motion of the head in response to  stimulation (commonly a smell), allowing orientation and movement towards the stimulus by alternating exposure of sensory receptors on either side of the body (see also "tropotaxis")



  • Lamnidae = family of sharks, order "Lamniformes" (aka Mackerel sharks), including only known "endothermic" shark species 

  • Lamniformes = order of sharks (families 1. Lamnidae, 2. Mitsukurinidae, 3. Megachasmidae, 4. Cetorhinidae, 5. Alopiidae, 6. Odontaspididae)

  • Lateral line = sensory organ running parallel along each side of a fish's body, capable of detecting water displacement and changes in pressure

  • Looping = an "agonistic" display of swimming in a spiral loop



  • Mate choice = when choice of a reproductive partner is non-random, but rather based on favourable traits. Commonly "female mate choice" (when female chooses male), but also sometimes "male mate choice" (when male chooses female) or "mutual mate choice" (when both male and female choose each other) (see also "sexual selection")

  • Mechanoreception = sensory ability to detect displacements in water (see "Lateral line")

  • Megachasmidae = family of sharks, order "Lamniformes" (aka Megamouth sharks)

  • Megalodon = common name used to refer to an enormous, extinct shark species OtodusCarcharocles megalodon

  • Marine Protected Area (MPA) = an area managed to protect marine ecosystems, processes, habitats, and species, which can contribute to the restoration and replenishment of resources for social, economic, and cultural enrichment

  • Mermaid's purse = slang term used for shark / ray egg cases (see "Oviparity")

  • Mesopelagic Zone = aka Twilight Zone, relatively shallow depth layer in the ocean, from 200 - 1000 me, where light can easily penetrate (between the "Epipelagic Zone" and "Bathypelagic Zone")

  • Mesopredator = a mid-ranking predator (below the "apex predator") in the mid-  trophic levels, which typically preys on smaller animals

  • Mesothermic / Mesotherm = a relatively rare form of "endothermy" whereby an organism elevates its body temperature above that of the environment using metabolic heat, but has little to no control to maintain a specific temperature range

  • Microplastics = extremely small pieces of plastic debris from the breakdown of discarded consumer products and industrial waste

  • Mitsukurinidae = family of sharks, order "Lamniformes" (aka Goblin sharks)

  • Monophyletic group = a group of organisms which have all evolved from a common ancestor

  • Mouthing = hunting and/or investigative behaviour; whereby shark grasps an object in it’s mouth briefly, releasing it without removing flesh



  • Natal site = place of birth (often referred to in terms of "philopatry")

  • Natural selection = the process whereby organisms better adapted to their environment tend to survive and produce more offspring

  • Neonate = a new-born animal

  • Neoselachii = subcohort of cohort "Euselachii", modern sharks and rays

  • Niche = aka ecological niche, the position of a species within an ecosystem and its ecological role within that system

  • Nictiting membrane = whitish membrane which can be drawn across the eye to for protection 

  • Noise pollution = anthropogenic sound (from drilling, seismic surveys, shipping, and using radar and sonar) which causes disturbance in the marine environment

  • Nursery habitat = area where juvenile marine animals live during the first months of life because the area offers ample food and/or protection from predators

  • Nutrient translocation = the movement of nutrients from one location to another, for example, from a feeding site to a defecation site



  • Odontaspididae = family of sharks, order "Lamniformes" (aka Sandtiger sharks)

  • Omnivore = an animal that eats a variety of food of both plant and animal origin (see "herbivore" and "carnivore")

  • Ontogeny / Ontogenetic =  the developmental history of an organism

  • Operant conditioning = learning process whereby an animal learns to associate an action with either a positive (reward) or a negative (punishment) response (see also "classical conditioning")

  • Oophagy / Oophagus =  aka intrauterine cannibalism, when embryos feed on unhatched eggs while still inside the mother's uterus (See also "Adelphophagy")

  • Order = a term used describe a group of "Families" in  taxonomic classification 

  • Orectolobidae = family of sharks, order "Orectolobiformes" (aka Wobbegongs)

  • Orectolobiformes = order of sharks (families 1. Orectolobidae, 2. Rhincodontidae, 3.Stegostomatidae, 4. Parascyllidae, 5. Hemiscyllidae, 6. Brachaeluridae, 7. Ginglymostomatidae)

  • Oviparous / Oviparity = egg-laying reproduction (as opposed to "ovoviviparity" and "viviparity")

  • Ovoviviparous / Ovoviviparity = reproduction whereby fully developed young hatch from an egg within the        uterus, having absorbed their yolk sac reserves, and are birthed soon after, not supplied nutrients via placenta (as opposed to "oviparity" and "viviparity")



  • Palatoquadrate protrusion = an "agonistic" behaviour of forward extension of the upper jaw, causing it to separate from the cranium and which may bare the upper teeth 

  • Parascyllidae = family of sharks, order "Orectolobiformes" (aka Collared Carpet sharks)

  • Parturition = the process of giving birth to offspring

  • Parturition habitat = environment where females give birth to their young

  • PAT Tag = aka Pop-Up Archival Tag, type of electronic tag, used to study movement, which automatically detaches from the shark for data download

  • Pectoral fin(s) = pair of fins found on the either side after a fish's head, used for orientation when swimming and in "agonistic displays" 

  • Pelagic = living in open water (as opposed to “benthic”)

  • Philopatry =  the tendency of animals  to return / remain near a particular site / area

  • Photophore = a light-producing organ in the skin

  • Placental viviparity = reproduction whereby live young are birthed after having been supplied with nutrients via a placenta-like structure (see "viviparity")

  • Poikilothermic / Poikilotherm = an organism with a variable body temperature that tends to fluctuate with the temperature of its environment

  • Polyphyodont dentition = aka "revolver dentition", whereby an animals teeth are continually replaced throughout life

  • Principal population = main breeding population of migratory sharks (as opposed to "accessory population")

  • Pristiophoridae = family of sharks, order "Pristiophoriformes" (aka  Saw sharks)

  • Pristiophoriformes = order of sharks (family 1. Pristiophoridae)

  • Pup = term used to describe shark offspring



  • Raking = an agonistic behaviour of forcefully striking of the upper jaw teeth against a "con/heterospecific", causing injury to the receiver 

  • Ramming = an "agonistic" display where a signaller uses it’s snout to forcefully strike a receiver, often causing retreat 

  • Ram ventilation = method of respiration, whereby the shark swims forwards to keep oxygenated water running over the gills (as opposed to "buccal pumping")

  • Recruitment = term used to describe juvenile animals surviving to maturity and becoming a part of the adult population

  • Red List [of Threatened Species] = List of wild species threatened with extinction, produced by the "IUCN"

  • Repetitive aerial gaping (RAG) = an agonistic behaviour (potentially due to frustration) consisting of rhythmic, exaggerated opening and closing of the jaws above the water surface, known only in white sharks 

  • Retia mirabella = countercurrent heat-exchangers found in sharks of the "Lamniform" family, which are responsible for "endothermy" 

  • Rhincodontidae = family of sharks, order "Orectolobiformes" (aka Whale sharks)

  • Revolver dentition = "polyphyodont dentition", teeth embedded into gums (rather than jaw, as seen in bony fish) and are continuously replaced throughout life

  • Rostral teeth = hardened tooth-like structures projecting from the extended rostrum in sawfish and sawsharks

  • Rostrum = the snout of a shark, which projects out from the head



  • Salinity = amount of salt dissolved in seawater

  • Scavenger = an animal which exploits food which available (due to another predator's hunting or natural mortality) without hunting the prey themselves

  • Scyliorhinidae = family of sharks, order "Carchariniformes" (aka Cat sharks)

  • Sexual Selection = "natural selection" occurring due to preferences of sexual partners for certain features (see also "mate choice")

  • Species = a term used in  taxonomic classification, referring to a group of individuals which are capable of reproducing together

  • Sphyrnidae = family of sharks, order "Carchariniformes" (aka Hammerhead sharks)

  • Spiracle(s) = a pair of vestigial gill slits behind the eye of some sharks, used to provide oxygenated blood directly to the eye and brain through separate vasculature

  • SPOT Tag = aka Smart Position or Temperature Transmitting Tag, type of electronic tag, used to study movement, which transmits data via satellite

  • Spyhopping = a shark raising a portion of its face out of the water, in order to clear the eye/s from the surface to inspect objects

  • Squlidae = family of sharks, order "Squaliformes" (aka Dogfish sharks)

  • Squatinidae = family of sharks, order "Squatiniformes" (aka Angel sharks)

  • Squatiniformes = order of sharks (family 1. Squatinidae)

  • Squaliformes = order of sharks (families 1. Squlidae, 2. Echinorhinidae)

  • Squalomorphii = superorder, squalomorph sharks (Orders 1. Hexanchiformes, 2. Squaliformes, 3.    Pristiophoriformes)

  • Squatinomorphii = superorder, squatinomorphs (Orders 1. Squatinomorphes)

  • Stegostomatidae = family of sharks, order "Orectolobiformes" (aka Zebra sharks)

  • Stenohaline = only able to survive  a narrow salinity range (as opposed to "euryhaline"), common in "Elasmobranchs" 

  • Stomach contents analysis = scientific study of the feeding habits of fish and other animals based upon analysis of stomach contents

  • Sub-adult = an animal which has advanced beyond the "Juvenile" stage and is close to, but has yet to reach sexual maturity 

  • Substrate = the earthy material at the bottom of a marine habitat, like dirt, rocks, sand, or gravel



  • Tail slapping = an agonistic behaviour consisting of whip-like lashing of the tail at/near the surface, hitting or directing splashes towards a competitor, known in white sharks and sandtiger sharks 

  • Term size = length at birth

  • Tesserae = highly mineralised plate-like tiles, coating the surface of "tessellated cartilage" in the "Chondrichthyan" skeleton

  • Tessellated cartilage = highly mineralised cartilage found in the vertebral column and jaw of "Chondrichthyans"

  • Threat display = communicates an individual’s ill ease at the close presence of another and often remind the recipient of the signaller’s ability to inflict harm, with the goal to force the competitor to flee without resorting to fighting, so gaining access to a resource, without risk of personal injury

  • Tonic Immobility = a state of paralysis which can be induced by flipping a shark on its back or overloading the electromagnetic sense (See also "Ampullae of Lorenzini")

  • Total length (TL) = standard measure used to describe the size of sharks, measured from the tip of the "rostrum" in a straight line to the tip of the upper "caudal fin"

  • Triakidae = family of sharks, order "Carchariniformes" (aka Smoothhound sharks)

  • Trophic cascade = an ecological phenomenon triggered by the addition/removal of a species into the food chain, which results in dramatic changes to the ecosystem structure 

  • Trophic level = the group of organisms within an ecosystem which occupy the same level in a food chain (See "Primary producer", "Heterotroph", "Mesopredator", "Apex predator")

  • Tropotaxis = orientation by simultaneous comparison of olfactory stimuli from paired receptors             (see "klinotaxis").



  • UNESCO World Heritage Site = an area or site with outstanding value to humanity, which is protected and maintained for future generations to enjoy

  • Upwelling = the process of seawater rising from depth to replace surface waters with cooler, more productive (aka nutrient-rich) water



  • Vertebral band analysis = method used to estimate the age of a shark by counting the annual/biannual deposition of a new band of cartilage over the skeleton

  • Viviparous / Viviparity = reproduction birthing live young (as opposed to "oviparity" and "ovoviviparity")



  • Young-of-the-Year (YOY) = juvenile animals born within the last year


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