Golden poison frog

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Golden poison frog
Schrecklicherpfeilgiftfrosch-01.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Amphibia
Order: Anura
Family: Dendrobatidae
Genus: Phyllobates
Species:
P. terribilis
Binomial name
Phyllobates terribilis
Myers  [ fr ], Daly, and Malkin, 1978 [2]

The golden poison frog (Phyllobates terribilis), also known as the golden dart frog or golden poison arrow frog, is a poison dart frog endemic from the rainforests of Colombia. The golden poison frog has become endangered due to habitat destruction within its naturally limited range. Despite its small size, this frog is considered to be the most poisonous extant animal species on the planet.

Contents

Taxonomy and etymology

The golden poison frog was described as Phyllobates terribilis in 1978 by herpetologists Charles W. Myers and Borys Malkin as well as biochemist John W. Daly; [3] the species name terribilis is a reference to the deadly toxins present in the skin secretions of this species. [2] Myers' research was based on hundreds of specimens collected on an expedition to the Quebrada Guangui and La Brea regions of the Colombian rainforest, and a breeding colony of 18 frogs established at the American Museum of Natural History. [2] [4]

Distribution and habitat

The golden poison frog is endemic to humid forests of the Pacific coast of Colombia in the Cauca and Valle del Cauca Departments in the Chocó Rainforest. [3] [5] The optimal habitat of this species is the rainforest with high rain rates (5 m or more per year), altitudes from sea level to 200 m elevation, temperatures of at least 26 °C, and relative humidity of 80–90%.[ citation needed ] It is known only from primary forest. The eggs are laid on the ground; the males transport the tadpoles to permanent pools. [1] Its range is less than 5,000 square km; destruction of this habitat has contributed to P. terribilis becoming an endangered species. [6]

Description

The golden poison frog is the largest species of the poison dart frog family, and can reach a weight of nearly 30 grams with a length of 6 cm as adults. [7] Females are typically larger than males. [4] The adults are brightly colored, while juvenile frogs have mostly black bodies with two golden-yellow stripes along their backs. The black fades as they mature, and at around 18 weeks of age the frog is fully colored. [4] The frog's color pattern is aposematic (a coloration to warn predators of its toxicity). [8] Despite their common name, golden poison frogs occur in four main color varieties or morphs: [9] [10] [11]

Yellow

The yellow morph is the reason Phyllobates terribilis has the common name golden poison frog. These frogs can be pale yellow to deep, golden yellow in color. Yellow Phyllobates terribilis specimens are found in Quebrada Guangui, Colombia. [12]

Mint green

The largest morph of Phyllobates terribilis exists in the La Brea and La Sirpa areas in Colombia; despite the name "mint green" these frogs can be metallic green, pale green, or white. [2] [12]

Orange

Orange examples of Phyllobates terribilis exist in Colombia, as well. They tend to be a metallic orange or yellow-orange in color, with varying intensity. They have been observed living near yellow specimens in Quebrada Guangui, Colombia, and it is unclear to what extent these represent an individual subpopulation or locality distinct from the yellow morph. [2]

Orange blackfoot

The orange blackfoot morph is a captive bred line established by Tesoros de Colombia, a Colombian company that aims to reduce poaching of wild dart frogs by breeding rare species and flooding the pet trade with low cost animals to decrease the value of wild specimens to poachers. [10] This morph is golden yellow to a deep orange. They have dark markings on their feet, throat, vent, and rump that range from distinct black to nearly absent or speckled grey. [10]

Ecology and behavior

Male Phyllobates terribilis 'orange blackfoot' calling Trilling terribilis.jpg
Male Phyllobates terribilis 'orange blackfoot' calling

The frog is normally diurnal; golden poison frogs live evenly spaced without forming larger congregations. [9]

Diet

This species is an unspecialized ambush hunter; an adult frog can eat food items much larger in relation to its size than most other dendrobatids. [9] [13] The main natural sources of food of P. terribilis are the ants in the genera Brachymyrmex and Paratrechina , but many kinds of insects and other small invertebrates can be eaten, specifically termites and beetles, which can easily be found on the rainforest floor.[ citation needed ] Tadpoles feed on algae, mosquito larvae, and other edible material that may be present in their environment.[ citation needed ]

Breeding

Phyllobates terribilis in a bromeliad Yellow poison dart frog at Chester Zoo.jpg
Phyllobates terribilis in a bromeliad

Males advertise to receptive females with a trilling call.[ citation needed ] Golden poison frogs are notable for demonstrating tactile courtship during reproduction, each partner stroking its mate's head, back, flanks, and cloacal areas prior to egg deposition. [14] The eggs are fertilized externally. The golden poison frogs lay their eggs on the ground, hidden beneath leaf litter. [15] Once the tadpoles emerge from their eggs, they stick themselves to the mucus on the backs of their parents. The adult frogs carry their young into the canopy, depositing them in the pools of water that accumulate in the centre of bromeliads and water-filled tree holes. [16] [14] The tadpoles feed on algae and mosquito larvae in their nursery.

Predators

Golden poison frogs are so toxic that adult frogs likely have few – if any – predators. [4] The snake species Leimadophis epinephelus has shown resistance to several frog toxins including batrachotoxin, and has been observed to eat juvenile frogs without ill effects. [2]

Toxicity

The golden poison frog is one of the most poisonous animals on the planet; these frogs produce deadly alkaloid batrachotoxins in their skin glands as a defense against predators. [16] [17] To become poisoned a predator generally must attempt to consume the frog, although this species is so toxic that even touching an individual frog can be dangerous. [16] This extraordinarily lethal poison is very rare. Batrachotoxin is found only in three poisonous frogs from Colombia (all genus Phyllobates ), a few birds from Papua New Guinea, and four Papuan beetles of the genus Choresine in the family Melyridae. [18] [19] Batrachotoxin affects the sodium channels of nerve cells. While it is unknown how the frog avoids poisoning itself, other species of poisonous frogs have been demonstrated to express a "toxin sponge" protein in blood plasma, internal organs, and muscle that binds and sequesters the toxin so as to prevent autointoxication. [20]

Mechanism

Chemical structure of batrachotoxin, the toxic steroidal alkaloid from the skin of Phyllobates Batrachotoxin skeletal.svg
Chemical structure of batrachotoxin, the toxic steroidal alkaloid from the skin of Phyllobates

Batrachotoxin binds to, and irreversibly opens, the sodium channels of nerve cells leaving the muscles in an inactive state of contraction, which can lead to paralysis, heart fibrillation, heart failure, and death. [21] The average dose carried will vary between locations, and consequent local diet, but the average wild golden poison frog is generally estimated to contain about one milligram of poison, enough to kill between 10 and 20 humans, or up to two African bull elephants. [22] [16] Smaller doses have been shown to cause seizures, salivation, muscle contractions, dyspnoea and death in mice: the subcutaneous LD50 is just 0.2 μg/kg, although low doses such as 0.01 μg/kg and 0.02 μg/kg may be lethal. [17] Myers et al. estimate that the lethal dose for humans is between 2.0 and 7.5 μg. [17]

Phyllobates species are used by native Colombians to poison their blow-gun darts Panam Embera0609.jpg
Phyllobates species are used by native Colombians to poison their blow-gun darts

Synthesis

Golden poison frogs appear to rely on the consumption of small insects or other arthropods to synthesize batrachotoxin; frogs kept in captivity fed on commercially available feeder insects will eventually lose their toxicity, and frogs bred in captivity are considered non-toxic. [9] [4] It is not clear which prey species supplies the potent alkaloid that gives golden poison frogs their exceptionally high levels of toxicity, or whether the frogs modify another available toxin to produce a more efficient variant, as do some of the frogs from the genus Dendrobates . [22] Scientists have suggested the crucial prey item may be a small beetle from the family Melyridae. At least one species of these beetles produces the same toxin found in golden poison frogs. Their relatives in Colombian rainforests could be the source of the batrachotoxins found in the highly toxic Phyllobates frogs of that region. [19] [23]

Use by indigenous people

Golden poison frogs are a very important frog to the local indigenous cultures, such as the Emberá and Cofán people in Colombia's rainforest. [4] The frog is the main source of the poison in the darts used by the natives to hunt their food. The Emberá people carefully expose the frog to the heat of a fire, and the frog exudes small amounts of poisonous fluid. The tips of arrows and darts are soaked in the fluid, and remain deadly for two years or longer. [13]

In captivity

Phyllobates terribilis in captivity Phyllobates terribilis vivarium.jpg
Phyllobates terribilis in captivity

The golden poison frog is a popular vivarium subject due to its bright color and bold personality in captivity. [10] [11] [9] Despite its dangerous toxicity in the wild, captive specimens raised without their natural food sources are non-toxic in captivity. [11] Due to their small range in the wild, poaching for the pet trade formerly represented a serious threat to the survival of the species. Due to efforts of frog breeders like Tesoros de Colombia, captive bred frogs are now widely available for the pet trade. As these specimens are legal, non-toxic, healthier, and less expensive when compared to poached animals, the demand for illegally obtained wild caught specimens has decreased. [10] Today, the IUCN estimates that the majority of golden poison frogs sold for the pet trade are legally produced from captive lines, and estimates the threat from collection for the pet trade to be small. [1]

Related Research Articles

<span class="mw-page-title-main">Poison dart frog</span> Family of amphibians

Poison dart frog is the common name of a group of frogs in the family Dendrobatidae which are native to tropical Central and South America. These species are diurnal and often have brightly colored bodies. This bright coloration is correlated with the toxicity of the species, making them aposematic. Some species of the family Dendrobatidae exhibit extremely bright coloration along with high toxicity — a feature derived from their diet of ants, mites and termites— while species which eat a much larger variety of prey have cryptic coloration with minimal to no amount of observed toxicity. Many species of this family are threatened due to human infrastructure encroaching on their habitats.

<span class="mw-page-title-main">Batrachotoxin</span> Chemical compound

Batrachotoxin (BTX) is an extremely potent cardiotoxic and neurotoxic steroidal alkaloid found in certain species of beetles, birds, and frogs. The name is from the Greek word βάτραχος, bátrachos, 'frog'. Structurally-related chemical compounds are often referred to collectively as batrachotoxins. In certain frogs, this alkaloid is present mostly on the skin. Such frogs are among those used for poisoning darts. Batrachotoxin binds to and irreversibly opens the sodium channels of nerve cells and prevents them from closing, resulting in paralysis and death. No antidote is known.

<span class="mw-page-title-main">Blue poison dart frog</span> Species of amphibian

The blue poison dart frog or blue poison arrow frog is a poison dart frog found in the "forest islands" surrounded by the Sipaliwini Savanna in southern Suriname. Its indigenous Tiriyo name is okopipi. The name "azureus" comes from its azure blue color. While first described as a valid species and usually recognized as such in the past, recent authorities generally treat it as a morph of D. tinctorius, although a few treat it as a subspecies of D. tinctorius or continue to treat it as its own species. To what extent it differs from the blue D. tinctorius in southern Guyana, adjacent Pará (Brazil) and possibly far southwestern Suriname, is also a matter of dispute, and many herpetologists, as well as many people keeping poison dart frogs in captivity, have not distinguished these, with all commonly being identified as "azureus".

<span class="mw-page-title-main">Dyeing poison dart frog</span> Species of amphibian

The dyeing poison dart frog, also known as the cobalt poison frog, tinc, is a species of poison dart frog. It is among the most variably colored and largest species of poison dart frogs, typically reaching snout–vent lengths of about 50 mm (2.0 in). It is distributed in the eastern portion of the Guiana Shield, including parts of French Guiana, Guyana, Suriname, and Brazil. These types of frogs usually like to stay in the ground as it is easier to catch prey. They tend to also stay in bodies of water like rivers or climb trees. Because of this they mostly inhabit near the Amazon Rainforest. To mate they have special rituals and leave their tadpoles in freshwater.

<span class="mw-page-title-main">Green and black poison dart frog</span> Species of amphibian

The green-and-black poison dart frog, also known as the green-and-black poison arrow frog and green poison frog, is a brightly-colored member of the order Anura native to southern Central America and Colombia. This species has also been introduced to Oahu, Hawaii in an effort to lower mosquito numbers. It is one of the most variably colored species of poison dart frogs, after D. tinctorius, Adelphobates galactonotus and some Oophaga species. From a conservation standpoint, it is considered to be of least concern by the International Union for Conservation of Nature. Within the reptile and amphibian hobby, D. auratus remains one of the most commonly kept, and easiest-to-breed, dart frogs in captivity, as well as in zoos.

<span class="mw-page-title-main">Yellow-banded poison dart frog</span> Species of amphibian

The yellow-banded poison dart frog, also known as yellow-headed poison dart frog or bumblebee poison frog, is a poison dart frog from the genus Dendrobates of the family Dendrobatidae.

<i>Phyllobates bicolor</i> Species of amphibian

Phyllobates bicolor, or more commonly referred to as the black-legged poison dart frog, is the world's second-most toxic dart frog. Under the genus Phyllobates, this organism is often mistaken as Phyllobates terribilis, the golden poison frog, as both are morphologically similar. However, Phyllobatesbicolor is identifiable by the yellow or orange body and black or dark blue forelimbs and hindlegs, hence the name black-legged dart frog. Phyllobates bicolor are commonly found in tropical forests of the Chocó region of Colombia. The diurnal frogs live along the rainforest ground near streams or puddles that form. Notably, P. bicolor is a member of the family Dendrobatidae, or poison dart frog. P. bicolor, along with the rest of the Phyllobates species, produce a neurotoxin known as a batrachotoxin that inhibits specific transmembrane channels in cells. Due to this highly deadly toxin that the frogs secrete, many indigenous groups of the Colombian rainforest have extracted the toxins to create poison tipped darts used for hunting. During the breeding period, P. bicolor emits high pitched single notes as a mating call. As in all poison dart frogs, it is common for the father of tadpoles to carry the offspring on his back until they reach a suitable location for the tadpoles to develop. P. bicolor is an endangered species according to the IUCN red list. Currently, deforestation, habitat loss, and pollution pose the biggest threat to the species. Limited conservation efforts have been attempted to prevent further damage to the species. Despite this, there are still institutions such as the Baltimore National Aquarium in Baltimore, Maryland and the Tatamá National Natural Park in Colombia that are engaged in P. bicolor conservation efforts such as captive breeding.

<i>Phyllobates</i> Genus of amphibians

Phyllobates is a genus of poison dart frogs native to Central and South America, from Nicaragua to Colombia. There are 3 different Colombian species of Phyllobates, considered highly toxic species due to the poison they contain in the wild.

Arrow poisons are used to poison arrow heads or darts for the purposes of hunting and warfare. They have been used by indigenous peoples worldwide and are still in use in areas of South America, Africa and Asia. Notable examples are the poisons secreted from the skin of the poison dart frog, and curare, a general term for a range of plant-derived arrow poisons used by the indigenous peoples of South America.

<i>Phyllobates aurotaenia</i> Species of amphibian

Phyllobates aurotaenia is a member of the frog family Dendrobatidae, which are found in the tropical environments of Central and South America. First described by zoologist George Albert Boulenger in 1913, P. aurotaenia is known for being the third most poisonous frog in the world. It is the smallest of the poison dart frogs in the Phyllobates genus and is endemic to the Pacific coast of Colombia.

<span class="mw-page-title-main">Mimic poison frog</span> Species of amphibian

Ranitomeya imitator, is a species of poison dart frog found in the north-central region of eastern Peru. Its common names include mimic poison frog and poison arrow frog, and it is one of the best known dart frogs. It was discovered in the late 1980s by Rainer Schulte who later split it up into more subspecies; describing each as a specific color morph, and sometimes having a separate behavioral pattern. The acoustics, morphs, and behavior of the species have been extensively researched.

<span class="mw-page-title-main">Lehmann's poison frog</span> Species of amphibian

Lehmann's poison frog or the red-banded poison frog is a species of frogs in the family Dendrobatidae endemic to a small part of western Colombia. Its natural habitats are submontane tropical rainforests. It is threatened by habitat loss and collection for the pet trade, and the IUCN lists it as being "critically endangered". It was named after Colombian conservation biologist Federico Carlos Lehmann.

<i>Oophaga sylvatica</i> Species of amphibian

Oophaga sylvatica, sometimes known as its Spanish name diablito, is a species of frog in the family Dendrobatidae found in Southwestern Colombia and Northwestern Ecuador. Its natural habitat is lowland and submontane rainforest; it can, however, survive in moderately degraded areas, at least in the more humid parts of its range. It is a very common frog in Colombia, but has disappeared from much of its Ecuadorian range. It is threatened by habitat loss (deforestation) and agricultural pollution and sometimes seen in the international pet trade.

<span class="mw-page-title-main">Golfodulcean poison frog</span> Species of amphibian

The Golfodulcean poison frog or Golfodulcean poison-arrow frog is a species of frog in the family Dendrobatidae endemic to Costa Rica.

<span class="mw-page-title-main">Pumiliotoxin</span>

Pumiliotoxins (PTXs), are one of several toxins found in the skin of poison dart frogs. The frog species, P. bibronii also produces PTXs to deter predators. Closely related, though more toxic, are allopumiliotoxins, (aPTXs). Other toxins found in the skin of poison frogs include decahydroquinolines (DHQs), izidines, coccinellines, and spiropyrrolizidine alkaloids. Pumiliotoxins are very poisonous in high concentrations. Pumiliotoxins are much weaker than batrachotoxins, ranging between 100 and 1000 times less poisonous. There are three different types of this toxin: A, B and C, of which toxins A and B are more toxic than C. Pumiliotoxins interfere with muscle contraction by affecting calcium channels, causing partial paralysis, difficulty moving, hyperactivity, or death. The median lethal dose of pumiliotoxins A and B is 50 μg / mouse, 20 μg / mouse respectively, while the amount of pumiliotoxin is 200 μg / frog.

The golden poison frog is a poison dart frog in the family Dendrobatidae endemic to the Pacific coast of Colombia.

<span class="mw-page-title-main">Toxic bird</span> Birds that are poisonous to touch and eat

Toxic birds are birds that use toxins to defend themselves from predators. Although no known bird actively injects or produces venom, toxic birds sequester poison from animals and plants they consume, especially poisonous insects. Species include the pitohui and ifrita birds from Papua New Guinea, the European quail, the spur-winged goose, hoopoes, the bronzewing pigeon, and the red warbler.

<span class="mw-page-title-main">Red-backed poison frog</span> Species of amphibian

The red-backed poison frog is a species of frog in the family Dendrobatidae. It is an arboreal insectivorous species, and is the second-most poisonous species in the genus, after R. variabilis. Like many species of small, poisonous frogs native to South America, it is grouped with the poison dart frogs, and is a moderately toxic species, containing poison capable of causing serious injury to humans, and death in animals such as chickens. R. reticulata is native to the Amazon rainforest in Peru and Ecuador.

<i>Phyllobates samperi</i> Species of amphibian

Phyllobates samperi, formerly known as sp. aff. aurotaenia is a new species of hypertoxic poison dart frog, once cited as the "red" form of Phyllobates aurotaenia. It resembles in size and to some extent in colouration to P. aurotaenia, but genetically it is the sister species of the "terrible" frog P. terribilis. It can be distinguished from P. aurotaenia by the absence of abundant blue or silver specks or marbling in the venter and limbs, its uniform black or bluish-black body, and its orange or red, rather than green or yellow, stripes.

<span class="mw-page-title-main">Sira poison dart frog</span> Species of amphibian

Ranitomeya sirensis or the Sira poison frog is a species of poison dart frog found in the Amazonian rainforests of northern Bolivia, westernmost Brazil (Acre), and eastern Peru.

References

  1. 1 2 3 IUCN SSC Amphibian Specialist Group (2017). "Phyllobates terribilis". IUCN Red List of Threatened Species . 2017: e.T55264A85887889. doi: 10.2305/IUCN.UK.2017-3.RLTS.T55264A85887889.en . Retrieved 12 November 2021.
  2. 1 2 3 4 5 6 Myers, C.W.; Daly, J.W. & B. Malkin (1978). "A dangerously toxic new frog (Phyllobates) used by Embera Indians of western Colombia with discussion of blowgun fabrication and dart poisoning". Bulletin of the American Museum of Natural History. 161: 307–366. hdl:2246/1286.
  3. 1 2 Frost, Darrel R. (2022). "Phyllobates terribilis Myers, Daly, and Malkin, 1978". Amphibian Species of the World: An Online Reference. Version 6.1. American Museum of Natural History. doi:10.5531/db.vz.0001 . Retrieved 8 March 2022.
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  5. ↑ Acosta-Galvis, A.R. (2014). "Phyllobates terribilis Myers, Daly, & Malkin, 1978". Lista de los Anfibios de Colombia V12.2022. batrachia.com. Retrieved 8 March 2022.
  6. ↑ "Golden Poison Frog | National Geographic". Animals. 10 September 2010. Archived from the original on 26 May 2017. Retrieved 14 May 2020.
  7. ↑ "Largest poison-dart frog species". Guinness World Records. 13 January 2014. Retrieved 2 March 2022.
  8. ↑ Summers, Kyle; Clough, Mark E. (22 May 2001). "The evolution of coloration and toxicity in the poison frog family (Dendrobatidae)". Proceedings of the National Academy of Sciences. 98 (11): 6227–6232. Bibcode:2001PNAS...98.6227S. doi: 10.1073/pnas.101134898 . ISSN   0027-8424. PMC   33450 . PMID   11353830.
  9. 1 2 3 4 5 Lötters, Stefan (2007). Poison frogs: biology, species & captive care. Frank Mutschmann. Frankfurt am Main. pp. 431–433. ISBN   978-3-930612-62-8. OCLC   174929258.{{cite book}}: CS1 maint: location missing publisher (link)
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  11. 1 2 3 Clare, John (16 May 2012). "Care Tips For The Golden Dart Frog - Reptiles Magazine" . Retrieved 27 February 2022.
  12. 1 2 Márquez, Roberto; et al. (2012). "Range extension of the critically endangered true poison-dart frog, Phyllobates terribilis (Anura: Dendrobatidae), in western Colombia". Acta Herpetologica. 7 (2): 341–345. CiteSeerX   10.1.1.845.8708 .
  13. 1 2 "Atlas Dr. Pez : Phyllobates terribilis". Archived from the original on 13 December 2007. Retrieved 11 September 2007.
  14. 1 2 "Poison frogs". Smithsonian's National Zoo. 6 June 2016. Retrieved 25 January 2022.
  15. ↑ "Poison Frog | San Diego Zoo Animals & Plants". animals.sandiegozoo.org. Retrieved 25 January 2022.
  16. 1 2 3 4 "Golden Poison Frog". American Museum of Natural History. Retrieved 24 January 2022.
  17. 1 2 3 "Dart poison frogs and their toxins". ResearchGate.
  18. ↑ Maksim V. Plikus; Maksim V.; Astrowski, Alaiksandr A. (2014). "Deadly hairs, lethal feathers – convergent evolution of poisonous integument in mammals and birds". Experimental Dermatology. 23 (7): 466–468. doi: 10.1111/exd.12408 . PMID   24698054. S2CID   205127015.
  19. 1 2 Dumbacher, John P.; Wako, Avit; Derrickson, Scott R.; Samuelson, Allan; Spande, Thomas F.; Daly, John W. (2004). "Melyrid beetles (Choresine): A putative source for the batrachotoxin alkaloids found in poison-dart frogs and toxic passerine birds". Proceedings of the National Academy of Sciences. 101 (45): 15857–15860. Bibcode:2004PNAS..10115857D. doi: 10.1073/pnas.0407197101 . PMC   528779 . PMID   15520388.
  20. ↑ Abderemane-Ali, Fayal; Rossen, Nathan D.; Kobiela, Megan E.; Craig, Robert A.; Garrison, Catherine E.; Chen, Zhou; Colleran, Claire M.; O’Connell, Lauren A.; Du Bois, J.; Dumbacher, John P.; Minor, Daniel L. (6 September 2021). "Evidence that toxin resistance in poison birds and frogs is not rooted in sodium channel mutations and may rely on "toxin sponge" proteins". Journal of General Physiology. 153 (9): e202112872. doi:10.1085/jgp.202112872. ISSN   0022-1295. PMC   8348241 . PMID   34351379.
  21. ↑ Alvarez, Mariela C.; Wiley, Mary. "Phyllobates terribilis". Animal Diversity Web.
  22. 1 2 "USATODAY.com - Most poisonous creature could be a mystery insect". usatoday30.usatoday.com. Retrieved 8 July 2016.
  23. ↑ "WonderQuest: Most poisonous animal, Contentious ethanol debate, Do fish sleep?". 30 October 2013. Archived from the original on 30 October 2013.
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