great great major bird family widespread common species europe middle_east central parts north_africa generally resident sort woodland great migrate extremely harsh winters species numerous subspecies dna studies shown subspecies distinctive great separated distinct species southern asia japanese great remains widespread species genus great distinctive bird black head neck prominent white olive yellow variation numerous subspecies predominantly summer consume wider range food items winter months including small bats like cavity usually nesting hole tree female lays eggs parents raise chicks years pair raise nests raided infested adults hunted great adapted human changes environment common familiar bird urban parks gardens great important study species taxonomy great originally described current 18th century work scientific derived latin larger great treated ranging britain japan south islands indonesia described subspecies ascribed main species groups major group subspecies europe temperate asia north africa minor group subspecies occurred southeast russia japan northern southeast asia subspecies group found iran south asia indonesia subspecies treated separate species form thought form ring species gene flow subspecies theory abandoned sequences mitochondrial dna examined finding groups distinct zones groups result secondary contact temporary period isolation study published confirmed major group distinct minor groups diverged groups million years ago divergence major groups estimated half million years ago study examined hybrids representatives major minor groups meet hybrids rare suggesting reproductive barriers groups study recommended eastern groups split new species japanese minor great taxonomy followed authorities example world bird list volume treating species went traditional classification treating separate species retaining japanese great criticism nominate subspecies great widespread range stretching scandinavia middle_east subspecies restricted restricted islands remainder major subspecies representing glacial refuge populations dominance single uniform subspecies large area suggests nominate race rapidly large area glacial hypothesis supported genetic studies suggest recent genetic followed rapid population expansion genus held species family morphological genetic studies led splitting large genus great retained comprise lineage known non reference behaviour members clade genus largest family split species considered subspecies great closest relatives white green backed southern asia hybrids outside genus rare recorded blue coal probably marsh subspecies currently recognised subspecies great described found british isles major described found europe asia minor northern eastern southern siberia northern far mid valley described found northwestern africa described found portugal southern spain described found described found described found crete described found southern italy southern greece cyprus described found lebanon israel jordan syria described found southeastern northwestern iran described found north central southwestern iran described found southern far north iran afghanistan following subspecies treated separate species described ranges east extreme north west china described found described found north west china north west siberia description great large length distinctive appearance makes easy recognise nominate race major major bluish black crown black neck throat head white ear breast bright lemon yellow broad black mid line stripe running vent dull white spot neck turning greenish yellow upper rest green tinged olive wing green rest wing bluish grey white wing bar tail bluish grey white outer tips plumage female similar male colours overall intensely black line running belly narrower broken young birds like female dull olive brown tails defined white tips variation subspecies like nominate race slightly longer bill mantle slightly deeper green white tail tips ventral mid line stripe broader belly resembles nominate form white tail yellow like nominate subspecies larger bill blue slightly paler like paler similar nominate race brighter green bright yellow little white tail darker olive grey yellow pale cream similar green pale yellow resembles previous subspecies slightly paler like nominate mantle pale yellow intermediate nominate lacks white tail plumage pale white washed grey larger white patch grey tail wings slightly smaller smaller bill longer tail situation similar related subspecies group like larger bill darker like smaller bill darker grey flanks yellow wash juvenile birds colour male bird breast shown stronger sperm way male demonstrates reproductive superiority females higher levels increase intensity yellow breast colour enable sperm better withstand onslaught free synthesized bird obtained food bright colour male demonstrates ability obtain good nutrition width male ventral stripe varies individual selected females higher quality females apparently selecting males wider stripes voice great like vocal bird types calls songs calls generally sexes male vocal female rarely calls soft single notes pit contact calls loud adult males alarm territorial disputes familiar teacher teacher likened wheel proclaiming ownership territory times english folk considered saw rain little geographic variation calls south asian groups recently split great recognise react calls temperate great explanation great wide repertoire theory eponymous hero novel dead soldiers impression fort better defended case similarly calls gives impression territory densely occupied actually theory correct birds large socially dominant breed successfully distribution movements habitat great wide distribution found europe iceland northern scandinavia including numerous mediterranean islands north_africa found morocco algeria tunisia occurs middle_east parts central asia northern iran afghanistan northern asia far east northern china great occupies range habitats commonly found open deciduous woodland mixed forests forest edges dense forests including forests usually found forest northern siberia found north_africa prefers oak forests stands cedar palm east range siberia china willow birch forest woodlands habitats group central asia low higher altitudes occupies habitats ranging dense deciduous coniferous forests open areas scattered trees great generally migratory pairs usually remain near territory year round northern parts range young birds disperse parents territory usually far populations poor harsh winters meaning groups thousand birds northern europe baltic netherlands britain far southern balkans great unsuccessfully introduced united_states birds set free near cincinnati ohio failed established suggestions excellent control measure nearly led introduction new areas particularly united_states_of_america plan implemented birds later introduced established present status unclear behaviour diet feeding great primarily summer feeding insects spiders capture foliage prey taken include bugs ants flies flies beetles flies bees breeding season prefer feed protein rich young study published found great helped reduce damage apple undergo period early development fed number spiders possibly reasons autumn winter insect prey great add seeds diet seeds fruit usually come deciduous trees shrubs include seeds beech available readily table seeds bird tables particularly severe winters consume body weight seeds forage ground particularly years high beech mast production great join winter mixed species foraging flocks large food items large seeds prey dealt hold item held feet struck bill ready eat method great minutes feeding young adults hammer heads large insects easier consume remove gut gut chick growth great combine versatility considerable intelligence ability solve problems insight learning solve problem insight trial error england great learned break foil caps milk bottles delivered homes obtain cream behaviour noted spread rapidly decades great reported killing eating bats time seen hunt bats winter bats food scarce recorded tools needle bill extract larvae hole tree individual great noted attack kill extent eat small birds feeding spots finland breeding great breeders establish breeding territories territories established late january defence begins late winter early spring territories usually successive years pair dies long brood raised successfully females likely disperse new territories nest previous year pair reason birds disperse females travelling males establish new territories great socially extra pair frequent study germany found nests contained offspring fathered parents breeding male chicks result great seasonal breeders exact timing breeding varies number factors importantly location breeding occurs january september europe breeding season usually begins march israel exceptional records breeding months october december sunlight daytime temperatures affect breeding timing study found strong timing laying peak abundance prey turn temperature individual level younger females tend start laying later older females great cavity breeding hole usually inside tree occasionally wall rock face readily nest boxes nest inside cavity built female plant grasses moss hair wool feathers number clutch large common clutch size smaller birds start laying later lower density competitors higher second tend smaller affects clutch size great offshore islands laying smaller larger eggs mainland birds eggs white red spots female duties fed male bird close disturbed timing hatching best peak availability prey manipulated environmental conditions change laying egg delaying beginning laying eggs period days chicks like hatched blind feathers begin unusual birds having plumage coloured similar parents species coloured avoid predation yellow attracts attention parents easier find low light signal fitness win parents attention patch turns white age months size bird grows chicks fed parents usually receiving food day parents provision chicks food aid nest removing difference feeding effort sexes period days chicks independent parents days feeding continue independence lasting days chicks brood long days second brood second weaker immune systems body condition lower juvenile survival rate depression occurs offspring produced result mating close relatives reduced fitness reduced fitness generally considered consequence increased expression offspring natural populations major avoided dispersal individuals birthplace reduces chance mating close relative ecology predator great young second higher risk partly hawk greater need food developing young nests great raided great spotted particularly nesting certain types nest boxes nest predators include introduced grey britain able nesting adults species biting described isolated described great central europe common nests blue great originally specialist dry crowded conditions chicken runs enabled flourish new host clown beetle beetle feeds larvae beetles remain deserted nests breed elevated temperatures produced brooding birds preferred hosts relationship humans great popular garden bird performances feeding nuts seed willingness nest boxes valuable study subject particularly useful model study evolution life history traits particularly clutch size study literature database search found articles relating major period great generally adjusted human modifications environment common better breeding success areas forest cover adapted human modified habitats common urban areas example breeding population city sheffield city half million people estimated individuals adapting human environments song observed change noise urban environments areas low frequency background noise pollution song higher frequency areas expanded range moving northwards scandinavia scotland south israel egypt total population estimated million birds range million km2 million declines population areas poorer quality habitats large range high numbers mean great considered threatened classed concern iucn red list
Great tit