The common frog or grass frog (Rana temporaria), also known as the European common frog, European common brown frog, European grass frog, European Holarctic true frog, European pond frog or European brown frog, is a semi-aquaticamphibian of the family Ranidae, found throughout much of Europe as far north as Scandinavia and as far east as the Urals, except for most of the Iberian Peninsula, southern Italy, and the southern Balkans. The farthest west it can be found is Ireland. It is also found in Asia, and eastward to Japan. The nominative, and most common, subspecies Rana temporaria temporaria is a largely terrestrial frog native to Europe. It is distributed throughout northern Europe and can be found in Ireland, the Isle of Lewis and as far east as Japan.[2]
Common frogs metamorphose through three distinct developmental life stages — aquatic larva, terrestrial juvenile, and adult. They have corpulent bodies with a rounded snout, webbed feet and long hind legs adapted for swimming in water and hopping on land. Common frogs are often confused with the common toad (Bufo bufo), but frogs can easily be distinguished as they have longer legs, hop, and have a moist skin, whereas toads crawl and have a dry 'warty' skin. The spawn of the two species also differs, in that frog spawn is laid in clumps and toad spawn is laid in long strings.
There are 3 subspecies of the common frog, R. t. temporaria, R. t. honnorati and R. t. palvipalmata. R. t. temporaria is the most common subspecies of this frog.
Description
The adult common frog has a body length of 6 to 9 centimetres (2.4 to 3.5 in).[3] In addition, its back and flanks vary in colour from olive green[2] to grey-brown, brown, olive brown, grey, yellowish and rufous.[4] However, it can lighten and darken its skin to match its surroundings.[2] Some individuals have more unusual colouration—both black and red individuals have been found in Scotland, and albino frogs have been found with yellow skin and red eyes. During the mating season the male common frog tends to turn greyish-blue (see video below). The average mass is 22.7 g (0.80 oz); the female is usually slightly larger than the male.[2]
The flanks, limbs and backs are covered with irregular dark blotches[2] and they usually sport a chevron-shaped spot on the back of their neck and a dark spot behind the eye.[4] Unlike other amphibians, common frogs generally lack a mid-dorsal band but, when they have one, it is comparatively faint.[4] In many countries moor frogs have a light dorsal band which easily distinguishes them from common frogs. The underbelly is white or yellow (occasionally more orange in females) and can be speckled with brown or orange.[2] The eyes are brown with transparent horizontal pupils, and they have transparent inner eyelids to protect the eyes while underwater, as well as a 'mask' which covers the eyes and eardrums.[2] Although the common frog has long hind legs compared to the common toad, they are shorter than those of the agile frog with which it shares some of its range. The longer hind legs and fainter colouration of the agile frog are the main features that distinguish the two species.
Males are distinguishable from females as they are smaller and have hard swellings, known as nuptial pads, on the first digits of the forelegs, used for gripping females during mating.[3][2] During the mating season males' throats often turn white, and their overall colour is generally light and greyish, whereas the female is browner, or even red.[4]
These smooth-skinned frogs can grow to an average weight of 22.7 grams and length of seven to ten centimeters (2.8-3.9 in) with colors varying from gray to green, brown, yellow, or red and may be covered in blotches.[5] The underbelly is white or yellow often with speckles.[2]
Habitat and distribution
Outside the breeding season, common frogs live a solitary life in damp wetlandniches near ponds or marshes or among long riparian grass.[6] They are normally active for much of the year, only hibernating in the coldest months.[4] In the most northern extremities of their range they may be trapped under ice for up to nine months of the year, but recent studies have shown that in these conditions they may be relatively active at temperatures close to freezing.[6] In the British Isles, common frogs typically hibernate from late October to January. They will re-emerge as early as February if conditions are favorable, and migrate to bodies of water such as garden ponds to spawn.[7] Where conditions are harsher, such as in the Alps, they emerge as late as early June. Common frogs hibernate in running waters, muddy burrows, or in layers of decaying leaves and mud at the bottom of ponds or lakes primarily with a current. The oxygen uptake through the skin suffices to sustain the needs of the cold and motionless frogs during hibernation.[2][4][8]
Common frogs are found throughout much of Europe as far north as northern Scandinavia inside the Arctic Circle and as far east as the Urals, except for most of Iberia, southern Italy, and the southern Balkans. Other areas where the common frog has been introduced include the Isle of Lewis, Shetland, Orkney and the Faroe Islands. It is also found in Asia, and eastward to Japan.[2][9]
The common frog has long been thought to be an entirely introduced species in Ireland,[7] however, genetic analyses suggest that particular populations in the south west of Ireland are indeed indigenous to the country.[10] The authors propose that the Irish frog population is a mixed group that includes native frogs that survived the last glacial period in ice free refugia, natural post-glacial colonizers and recent artificial introductions from Western Europe.[10][11]
Genetic population structure
The common frog is a very widely distributed species, being common all throughout Europe and northwest Asia. The more peripheral subpopulations of common frogs are significantly less in number, as well as less genetically variable. There is a steep genetic decline when approaching the periphery of the common frog's distribution range.[12] Additionally, genetic differentiation of common frog subpopulations tends to decrease in relation to increasing latitude.[12] The colder climates create a strong selective pressure favoring common frog populations able to behaviorally thermoregulate at a high degree.[13]
Conservation
Long-term impact of diseases
Of the many diseases affecting common frogs, one of the most deadly has been the Ranavirus, which has been responsible for causing declines in amphibian populations worldwide. Two of the main, and most deadly, symptoms caused by Ranavirus towards common frogs are skin ulcerations and hemorrhaging.[14] Mortality rates associated with the disease are very high, in some events it is observed to be over 90%.[14] Deaths caused by Ranavirus occur in all stages of common frog development and are concentrated mostly during the summer months. Overall, common frog populations affected by ranavirus experience consistent and substantial declines in population size. Recent metagenomics studies on common frogs from the United Kingdom have revealed widespread viral infections of Rana tamanavirus, a positive-sense RNA virus that is closely related to Tamana bat virus, as of yet no pathology or effect on life history traits have been observed.[15]
Impact of urbanization
Due to the widespread nature of Rana temporaria, common frogs can make their homes in both urban and rural environments. However, many of the populations living in urban environments are subject to the detrimental effects of urbanization. The construction of roads and buildings – absolute barriers to migration – has stymied gene flow and drift between urban populations of common frogs, leading to lower levels of genetic diversity in urban common frog populations compared to their rural counterparts.[16] Urban common frog populations also experience higher levels of mortality and developmental abnormality, indicative of forced inbreeding.[16]
At metamorphosis, once the tadpole's fore legs have developed, the frog does not feed for a short time. Recently metamorphosed juvenile frog mostly feed on small insects like Collembola (hexapods), Acarina (mites and ticks), and small fly larvae. Rana temporaria tadpoles, however, mostly feed on algae and decomposed plants,[17] but once their hind legs develop, they become carnivorous.[18]
Adults
The common frog takes its place as an unspecialized and opportunistic feeder wherever it is located. In other words, common frogs will consume whatever prey that is most available and easy to capture.[19] This usually means that the common frog feeds by remaining idle and waiting until a suitable prey enters the frog's domain of capture. As a corollary, this also means that the common frog's diet changes depending on the season where the associated prey become the most abundant. In the summer, the common frog's diet mostly consists of adult crane flies and the larvae of butterflies and moths. To a slightly lesser extent, common frogs will feed on woodlice, arachnids, beetles, slugs, snails, and earthworms.[20][17][21][22] In addition, common frogs will typically feed on bigger prey as they become larger. Therefore, newly developed common frogs are limited to smaller insect prey, whereas larger frogs are able to consume a wide range of insects. Common frogs will hide in damp places, such as in the water, during the day, and at night, they will begin searching for food.
Reproduction and mating patterns
During the spring the frog's pituitary gland is stimulated by changes in external factors, such as rainfall, day length and temperature, to produce hormones which, in turn, stimulate the production of sex cells – eggs in the females and sperm in the male. The male's nuptial pad also swells and becomes more heavily pigmented.[23] Common frogs breed in shallow, still, fresh water such as ponds, with spawning commencing sometime between late February and late June, but generally in April over the main part of their range.[4]
Competition among males
Like its close cousin, the moor frog (R. arvalis), R. Temporaria does not exhibit territoriality which leads to lack of physical fighting among males. During breeding season, male common frogs undergo a period of a few days (less than 10 days) where they display rapid and frenzied breeding behavior,[24] during which the purpose of the male is to quickly find and mate with as many female frogs as possible. Higher rates of mating success in males typically have longer thumbs than single males,[25] which allows them to have a better grip on females.
Mating interactions
Around three years after being born, the common frog will return to its original site of birth and release a mating call. Males will be the first to arrive at the pond and await females as they enter. During this period of pre-female competition, the pond is significantly male dominant, and there is a large amount of intrasexual competition taking place.[25] The shallow portion of the pond, which is more suitable for egg laying, is more predominantly occupied by the larger males. However, once the females arrive, this territoriality quickly dissipates and male-female amplexed pairs are free to migrate wherever in the pond. Additionally, once engaged in an amplexus, it is rare for single males to attempt to displace or "take over" the paired male.[25]
It is also important to note the effect of size on a male common frog's mating strategies. Smaller frogs, during the pre-spawning period get displaced from the shallow areas of the pond. Therefore, they circumvent this issue by searching for females on the land or in areas of the pond where they first arrive.[24] Meanwhile, the larger frogs occupy the spawning site, where they encounter more amplexed pairs and therefore rely on their ability to displace amplexed males to secure a mate.[24] However, the frequency of these takeovers is not consistent.
Life cycle
Female common frog clutch sizes range from a few hundred up to 5,000 eggs. Many of these eggs form large aggregates that serve to thermoregulate as well as protect the developing embryo from potential predators. By bunching the eggs together, it raises the temperature of the embryo compared to the surrounding water, which is important because the rate of tadpole development is faster in higher temperatures.[26] Additionally, the eggs are typically laid in the shallower regions of the pond to prevent hypoxia-induced fatality of the embryos.[26]
It normally takes 2–3 weeks for the eggs to hatch. Afterwards, common frog larvae group up into schools where they help each other feed off of algae and larger plants, as well as avoid predators.[27] By June and July, most tadpoles will have metamorphosized, and the remaining time until winter is used to feed and grow larger.[27] Only the largest frogs will survive the winter, which places a large emphasis on rapid development until then. In fact, a common frog's rate of development correlates with temperature. In lower temperature regions, common frogs will hatch earlier and metamorphosize sooner than common frogs living in warmer climate regions.[27] Sexual maturity occurs only after three years, and common frogs will typically live between six and eight years.[26]
Development in the presence of predators
The presence of a predator in the early development of the tadpole has an effect on its metamorphosis traits. For instance, it can lead to a longer larval period and a smaller size and mass at metamorphosis.[28] Once the predator is removed, the growth rate of the tadpole returns to, or even exceeds, baseline. This influence of predator threat is only significant during early tadpole development.[28]
One of the common frog's most pervasive predators is the red-eared slider (Trachemys scripta elegans), which is a very invasive species of turtle.
Thermoregulation
As an ectotherm, the common frog is very reliant on temperature as it directly influences their metabolism, development, reproduction, muscle ability, and respiration. As such, common frogs at mid and high elevations have developed a unique set of strategies to survive in cold climates. In fact, it is due to the common frog's ability to thermoregulate so effectively that the species has been able to become so pervasive across a multitude of environments and climates, living as far north as the Arctic Circle in Scandinavia, which is further north than any other amphibian in the region.[13] Contrary to Lithobates sylvaticus (wood frogs), common frogs do not have the ability to freeze protect themselves by increasing their levels of blood glucose to serve as a cryoprotectant.[13] As a result, common frogs must rely on behavioral thermoregulation by seeking out warm microhabitats (such as in the soil or between rocks) during wintertime. Additionally, common frogs will commonly hibernate throughout the winter season in groups to provide bodily heating.[13]
Social behavior
Similar to other anuran species (Bufo americanus and Rana sylvatica), Rana temporaria are able to naturally discriminate others of its kind. Post-embryonic interaction with conspecifics is not necessary to induce associative behavior for common frogs as an adult. Rather, once common frog tadpoles have reached a certain age, they gain a strong innate associative tendency.[29]Rana temporaria tend to aggregate as the result of environmental pressures, such as temperature or predators.[30]
Common frogs have an important place in human ecology by controlling the insect populations. In particular, their consumption of mosquitos and other crop-damaging insects has been especially valuable. In addition, Rana temporaria, due to their ecological pervasiveness and relative abundance, have become a common laboratory specimen.[31]
Farming
R. temporaria are farmed.[33] Miles et al. 2004 provide improved ingredients for manufacturers of pellet food for farmed common frogs.[33]
Due to the spread of diseases such as ranavirus, the UK based amphibian charity Froglife advised the public to avoid transporting frogspawn, tadpoles or frogs from one pond to another, even if these are close by.[34] It has also been recommended not to place goldfish or exotic frog species in outdoor ponds as this could have a negative effect on the frog population.
References
^ abKuzmin, S., Ishchenko, V., Tuniyev, B., Beebee, T., Andreone, F., Nyström, P., Anthony, B.P., Schmidt, B., Ogrodowczyk, A., Ogielska, M., Bosch, J., Miaud, C., Loman, J., Cogalniceanu, D., Kovács, T. & Kiss, I. (2009). Rana temporaria (errata version published in 2016). The IUCN Red List of Threatened Species 2009: doi:10.2305/IUCN.UK.2009.RLTS.T58734A11834246.en
^Dunlop, David (26 February 2004). "Common Frog final"(PDF). Lancashire BAP. Archived from the original(PDF) on 27 September 2007. Retrieved 9 August 2007.
^ abTeacher, A. G. F.; Cunningham, A. A.; Garner, T. W. J. (10 June 2010). "Assessing the long-term impact of Ranavirus infection in wild common frog populations: Impact of Ranavirus on wild frog populations". Animal Conservation. 13 (5): 514–522. doi:10.1111/j.1469-1795.2010.00373.x. S2CID85889833.
^ abStojanova, A.; Mollov, I. (2008). "DIET AND TROPHIC NICHE OVERLAP OF THE MOOR FROG (Rana arvalis Nilsson, 1842) AND THE COMMON FROG (Rana temporaria L., 1758) FROM POLAND". S2CID83200707. {{cite journal}}: Cite journal requires |journal= (help)
^Houston, W. W. K. (October 1973). "The food of the Common frog, Rana temporaria, on high moorland in northern England". Journal of Zoology. 171 (2): 153–165. doi:10.1111/j.1469-7998.1973.tb02212.x. ISSN0952-8369.
^Trakimas, Giedrius; Jardine, Timothy D.; Barisevičiūtė, Rūta; Garbaras, Andrius; Skipitytė, Raminta; Remeikis, Vidmantas (6 July 2011). "Ontogenetic dietary shifts in European common frog (Rana temporaria) revealed by stable isotopes". Hydrobiologia. 675 (1): 87. doi:10.1007/s10750-011-0804-3. S2CID39126267.
^Griffiths, R. A.; Foster, J. P. (August 1998). "The effect of social interactions on tadpole activity and growth in the British anuran amphibians ( Bufo bufo , B. calamita , and Rana temporaria )". Journal of Zoology. 245 (4): 431–437. doi:10.1017/S0952836998008061.
Alexander SkarsgårdSkarsgård tahun 2016LahirAlexander Johan Hjalmar Skarsgård25 Agustus 1976 (umur 47)Stockholm, SwediaPekerjaanAktorTahun aktif1984–sekarangAnak1Orang tuaStellan Skarsgård (bapak) Alexander Johan Hjalmar Skarsgård (lahir 25 Agustus 1976) adalah aktor asal Swedia. Lahir di Stockholm, putra dari aktor Stellan Skarsgård, ia mulai berakting pada usia tujuh tahun tetapi berhenti pada usia 13 tahun. Setelah bertugas di Angkatan Laut Swedia, Skarsgård kembali ke duni…
Polish/German embryologist, physiologist, and neurologist For his grandson, see Robert Remak (mathematician). Robert RemakRemak c. 1850-1855Born12 July 1815Posen, PrussiaDied29 August 1865 (1865-08-30) (aged 50)Bad Kissingen, BavariaAlma materUniversity of BerlinKnown forEctoderm, mesoderm and endodermScientific careerFieldsEmbryologyPhysiologyNeurologyDoctoral advisorFerdinand Georg FrobeniusHermann Amandus Schwarz Robert Remak (26 July 1815 – 29 August 1865) was an …
У этого термина существуют и другие значения, см. Чайки (значения). Чайки Доминиканская чайкаЗападная чайкаКалифорнийская чайкаМорская чайка Научная классификация Домен:ЭукариотыЦарство:ЖивотныеПодцарство:ЭуметазоиБез ранга:Двусторонне-симметричныеБез ранга:Вторичн…
This article relies largely or entirely on a single source. Relevant discussion may be found on the talk page. Please help improve this article by introducing citations to additional sources.Find sources: 1995 South Ribble Borough Council election – news · newspapers · books · scholar · JSTOR (December 2022) Main article: South Ribble Borough Council elections Elections to South Ribble Borough Council were held on 4 May 1995. The whole council was up for …
Play written by Simon Gray Cell MatesPoster original West End productionWritten bySimon GrayDate premiered16 February 1995Place premieredAlbery Theatre, LondonOriginal languageEnglishGenreDramaOfficial site Cell Mates is a play by Simon Gray. It opened at the Albery Theatre, London on 16 February 1995,[1] starring Stephen Fry and Rik Mayall, with Gray himself directing. Despite having performed successfully for several weeks during the pre-London warm-up dates in Guildford and Watford th…
ScandalImmagine tratta dalla sigla della serie televisivaTitolo originaleScandal PaeseStati Uniti d'America Anno2012-2018 Formatoserie TV Generedrammatico, politico, thriller Stagioni7 Episodi124 Durata40-45 min (episodio) Lingua originaleinglese Rapporto16:9 CreditiIdeatoreShonda Rhimes Interpreti e personaggi Kerry Washington: Olivia Pope Tony Goldwyn: Fitzgerald Thomas Grant III Darby Stanchfield: Abby Whelan Guillermo Díaz: Diego Huck Muñoz Katie Lowes: Quinn Perkins Columbus Short…
Town in Devon, England Not to be confused with Oakhampton in New South Wales, Australia. Human settlement in EnglandOkehamptonBaptist Chapel, Fore Street, built 1889OkehamptonLocation within DevonPopulation5,922 (2011)OS grid referenceSX5895• London201 miles (323 km)Civil parishOkehamptonDistrictWest DevonShire countyDevonRegionSouth WestCountryEnglandSovereign stateUnited KingdomPost townOKEHAMPTONPostcode districtEX20Dialling code01837PoliceDevon …
American fast food restaurant chain For other uses, see White Castle (disambiguation). White Castle Management Co.White Castle Building No. 8, originally built in 1936 in Minneapolis, Minnesota, and later remodeled. The castle-like features mimic Chicago's Water Tower Pumping Station. White Castle no longer operates this building, which is currently an antique shop.Trade nameWhite CastleCompany typePrivateIndustryRestaurantsGenreFast foodFoundedSeptember 13, 1921; 102 years ago …
Belgian carom billiards player Jozef Philipoom Philipoom in 2013 (1964-05-27) 27 May 1964 (age 59) Medal record Men's three-cushion billiards Representing Belgium World Championship 1995 Grubbenvorst Three-cushion European Championship 1995 Prague Individual World Cup 1996/2 Porto Individual 2009/1 Sluiskil Individual 2009/5 Hurghada Individual Jozef Bel Philipoom (born 27 May 1964)[1] is a Belgian carom billiards player.[2][3][4] He won at the UMB Worl…
RAD54B المعرفات الأسماء المستعارة RAD54B, RDH54, RAD54 homolog B (S. cerevisiae), RAD54 homolog B معرفات خارجية الوراثة المندلية البشرية عبر الإنترنت 604289 MGI: MGI:3605986 HomoloGene: 8240 GeneCards: 25788 علم الوجود الجيني الوظيفة الجزيئية • RNA helicase activity• DNA translocase activity• ربط دي إن إي• GO:0004003 DNA helicase activity• nucleotide binding• نشاط هيد…
German rower (born 1964) For the Danish novelist, see Thomas Lange (novelist). For people of a similar name, see Thomas Lang (disambiguation). Thomas LangeLange in 1987Personal informationBorn (1964-02-27) 27 February 1964 (age 60)Eisleben, East GermanyHeight1.89 m (6 ft 2 in)Weight89 kg (196 lb)SportSportRowingClubSV Halle, Halle an der Saale Medal record Men's rowing Representing East Germany Olympic Games 1988 Seoul Single sculls World Championships 1983 Du…
HH The Emir Sheikh(صاحب السمو الأمير والشيخ)Rashid bin Saeed Al Maktoumراشد بن سعيد آل مكتوم Presiden Uni Emirat ArabReign10 September 1958 – 7 Oktober 1990PendahuluSaeed IIPenggantiMaktoum IIIPerdana Menteri Uni Emirat ArabMasa jabatan25 April 1979 – 7 Oktober 1990PresidenZayed bin Sultan Al NahyanWakilHamdan bin Mohammed Al NahyanMaktoum bin Rashid Al MaktoumPendahuluMaktoum bin Rashid Al MaktoumPenggantiMaktoum bin Rashid Al MaktoumW…
Lowland Scottish clan Clan RutherfordMottoNec sorte, nec fato (Neither by chance nor fate)[1]ProfileRegionScottish Borders[2]DistrictJedburgh[2]Clan Rutherford no longer has a chief, and is an armigerous clanHistoric seatRutherford Castle[2]Hunthill Castle[2]Eggerston Castle[2] Clan branches Rutherford of Rutherford (historic chiefs)[3]Rutherford of Chatto and Hunthill (senior cadets)[3]Rutherfurd of Edgerston[3] Clan Ruther…
يفتقر محتوى هذه المقالة إلى الاستشهاد بمصادر. فضلاً، ساهم في تطوير هذه المقالة من خلال إضافة مصادر موثوق بها. أي معلومات غير موثقة يمكن التشكيك بها وإزالتها. (مارس 2016) عز الدين تقسيم إداري البلد سوريا التقسيم الأعلى ناحية مركز الرستن تعديل مصدري - تعديل عز الدين …
Untuk untuk klub Liga Utama Rusia lainnya dari Krasnodar, lihat FC Kuban Krasnodar. Artikel ini bukan mengenai FC Krasnodar-2000. KrasnodarNama lengkapФутбольный клуб Краснодар(Klub Sepak Bola Krasnodar)JulukanByki (The Bulls), Hitam-HijauBerdiri22 Februari 2008; 16 tahun lalu (2008-Feb-22)StadionStadion Krasnodar, Krasnodar(Kapasitas: 33.000)PemilikSergey GalitskyKetuaSergey GalitskyManajerOleg KononovLigaLiga Utama Rusia2015–16ke-3Situs webSitus web resmi klu…
Optical system with resolution performance at the instrument's theoretical limit Memorial in Jena, Germany to Ernst Karl Abbe, who approximated the diffraction limit of a microscope as d = λ 2 n sin θ {\displaystyle d={\frac {\lambda }{2n\sin {\theta }}}} , where d is the resolvable feature size, λ is the wavelength of light, n is the index of refraction of the medium being imaged in, and θ (depicted as α in the inscription) is the half-angle subtended by the optical ob…
State electoral district of New South Wales, Australia Byron was an electoral district of the Legislative Assembly in the Australian state of New South Wales created in 1913, replacing Rous, and named after Cape Byron. With the introduction of proportional representation in 1920, Byron absorbed Lismore and Clarence and elected three members. With the end of proportional representation in 1927, it was redivided into the single-member electorates of Byron, Lismore and Clarence. In 1988, Byron was …
Mall of KudusLokasiKudusAlamatJl Simpang Tujuh, Demaan, Kota Kudus, Kudus, Jawa TengahTanggal dibuka2001; 23 tahun lalu (2001)PemilikPemkab KudusJumlah lantai4ParkirHalaman Mal Kudus atau Mall of Kudus (disebut juga MOK) adalah salah satu mal yang terletak di Desa Demaan, Kecamatan Kota Kudus, Kabupaten Kudus. Mal yang berdiri pada tahun 2001 ini terletak di sudut timur Alun-Alun Kudus, atau lebih dikenal sebagai Simpang Tujuh Kudus.[1][2] Mal ini terdiri dari empat lantai y…