Pseudis paradoxa
Encyclopedia
Pseudis paradoxa, known as the paradoxical frog or shrinking frog, is a species of hylid frog from South America
. Its name refers to the very large—up to 25 centimetres (9.8 in) long—tadpole
(typical of the Pseudis
genus), which in turn becomes an ordinary-sized frog, only about a quarter of its former length.
Pseudis paradoxa is green coloured with dark green or olive stripes. It inhabits ponds, lakes and lagoons from northern Argentina
, through the Pantanal
, Amazon
and the Guianas
, to Venezuela
and Trinidad
, with a disjunct
in the Magdalena River watershed
in Colombia
and adjacent far western Venezuela. The female frog lays eggs among water plants; the eggs develop into giant tadpoles.
These paradoxical amphibians feed on larvae, small insects and tiny invertebrates. The Paradoxical Frog is a nocturnal animal and spends most of its life in water.
When threatened the frog uses its strong toes with an extra joint to stir up the muddy bottom and hide. The frog also uses this mechanism to find food on the bottom of lakes and ponds.
In March 2008, scientists working from the Universities of Ulster
and United Arab Emirates
released findings of a study where the synthesised version of the skin compound pseudin-2
was able to stimulate the secretion of insulin in pancreatic cells under laboratory conditions without toxicity
to the cells. This synthetic medicine would be used in the treatment of Type 2 diabetes. Pseudin compounds are thought to have some antimicrobial functions in the Paradoxical Frog.
In his book Three Singles to Adventure, Gerald Durrell
mentions collecting the tadpoles of the paradoxical frog.
The British quiz show QI
, hosted by Stephen Fry
, claimed that this frog was the only animal to have babies larger than the parent. Apart from the fact that no species could survive such an energy debt in reproducing, there are a number of species where the young grow to be larger, or to have more body mass, in adolescence than in maturity, including species with a chrysalis form and oceanic species which cease to be mobile, with the newly sessile form absorbing various body parts from its previous incarnation.
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
. Its name refers to the very large—up to 25 centimetres (9.8 in) long—tadpole
Tadpole
A tadpole or polliwog is the wholly aquatic larval stage in the life cycle of an amphibian, particularly that of a frog or toad.- Appellation :...
(typical of the Pseudis
Pseudis
Pseudis is a genus of frogs in the Hylidae family, and are found in the Guianas, Colombia, Venezuela, Trinidad, southern Brazil, Paraguay, southeastern Peru, eastern Bolivia, northeastern Argentina and Uruguay....
genus), which in turn becomes an ordinary-sized frog, only about a quarter of its former length.
Pseudis paradoxa is green coloured with dark green or olive stripes. It inhabits ponds, lakes and lagoons from northern Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...
, through the Pantanal
Pantanal
The Pantanal is a tropical wetland and one of the world's largest wetland of any kind. Most of it lies within the Brazilian state of Mato Grosso do Sul, but it extends into Mato Grosso and portions of Bolivia and Paraguay, sprawling over an area estimated at between and...
, Amazon
Amazon Basin
The Amazon Basin is the part of South America drained by the Amazon River and its tributaries that drains an area of about , or roughly 40 percent of South America. The basin is located in the countries of Bolivia, Brazil, Colombia, Ecuador, Guyana, Peru, and Venezuela...
and the Guianas
The Guianas
The Guyanas or the Guianas refers to a region in north-eastern South America which includes the following three territories:* French Guiana, an overseas department of France;...
, to Venezuela
Venezuela
Venezuela , officially called the Bolivarian Republic of Venezuela , is a tropical country on the northern coast of South America. It borders Colombia to the west, Guyana to the east, and Brazil to the south...
and Trinidad
Trinidad
Trinidad is the larger and more populous of the two major islands and numerous landforms which make up the island nation of Trinidad and Tobago. It is the southernmost island in the Caribbean and lies just off the northeastern coast of Venezuela. With an area of it is also the fifth largest in...
, with a disjunct
Disjunct distribution
In biology, a taxon with a disjunct distribution is one that has two or more groups that are related but widely separated from each other geographically...
in the Magdalena River watershed
Magdalena River Valley
The Magdalena River Valley is a valley in Colombia located within the Colombian Andes mountain ranges. The valley is specifically located between the Cordillera Central and Cordillera Oriental and crossed by the river of the same name, the Magdalena River....
in Colombia
Colombia
Colombia, officially the Republic of Colombia , is a unitary constitutional republic comprising thirty-two departments. The country is located in northwestern South America, bordered to the east by Venezuela and Brazil; to the south by Ecuador and Peru; to the north by the Caribbean Sea; to the...
and adjacent far western Venezuela. The female frog lays eggs among water plants; the eggs develop into giant tadpoles.
These paradoxical amphibians feed on larvae, small insects and tiny invertebrates. The Paradoxical Frog is a nocturnal animal and spends most of its life in water.
When threatened the frog uses its strong toes with an extra joint to stir up the muddy bottom and hide. The frog also uses this mechanism to find food on the bottom of lakes and ponds.
In March 2008, scientists working from the Universities of Ulster
University of Ulster
The University of Ulster is a multi-campus, co-educational university located in Northern Ireland. It is the largest single university in Ireland, discounting the federal National University of Ireland...
and United Arab Emirates
United Arab Emirates University
United Arab Emirates University was established in 1976, and is the oldest of the three government-sponsored institutions of higher learning in the United Arab Emirates compared to the Higher Colleges of Technology and Zayed University...
released findings of a study where the synthesised version of the skin compound pseudin-2
Pseudin
Pseudin is a peptide derived from Pseudis paradoxa.Pseudins have some antimicrobial function.There are several different forms:* pseudin-1* pseudin-2 -- has been proposed as a treatment for type 2 diabetes.* pseudin-4...
was able to stimulate the secretion of insulin in pancreatic cells under laboratory conditions without toxicity
Toxicity
Toxicity is the degree to which a substance can damage a living or non-living organisms. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell or an organ , such as the liver...
to the cells. This synthetic medicine would be used in the treatment of Type 2 diabetes. Pseudin compounds are thought to have some antimicrobial functions in the Paradoxical Frog.
In his book Three Singles to Adventure, Gerald Durrell
Gerald Durrell
Gerald "Gerry" Malcolm Durrell, OBE was a naturalist, zookeeper, conservationist, author and television presenter...
mentions collecting the tadpoles of the paradoxical frog.
The British quiz show QI
QI
QI is a British comedy panel game television quiz show created and co-produced by John Lloyd, hosted by Stephen Fry, and featuring permanent panellist Alan Davies. Most of the questions are extremely obscure, making it unlikely that the correct answer will be given...
, hosted by Stephen Fry
Stephen Fry
Stephen John Fry is an English actor, screenwriter, author, playwright, journalist, poet, comedian, television presenter and film director, and a director of Norwich City Football Club. He first came to attention in the 1981 Cambridge Footlights Revue presentation "The Cellar Tapes", which also...
, claimed that this frog was the only animal to have babies larger than the parent. Apart from the fact that no species could survive such an energy debt in reproducing, there are a number of species where the young grow to be larger, or to have more body mass, in adolescence than in maturity, including species with a chrysalis form and oceanic species which cease to be mobile, with the newly sessile form absorbing various body parts from its previous incarnation.