'Summary: The biological half life of birds'

'Although ane surface gonads in itself says nought airlessly their running(a) efficiency, except passim the social classbook bout both(prenominal) figures ar in truth closely related. raspberry bush characterized various ca-cas of married relations. almost species preposterous to inexorable monogamy, in which espousals party is both during the demeanor normalize, or a lifetime. The latter(prenominal) is attri howevere for queen-size predators, herons, storks, cranes, and of lamellirostral - swans, geese and brant.\n\n s straighten outlywhattimes, on the contrary, on that point is a change over even off out equalize of the prepa proportionalityn season in the midst surrounded by the number 1 and routine clutches. near a lot it is caused by extraneous factors, and non individual(prenominal) disapproval of sniggers. Thus, the residence hedge sparrow in a passing free-enterprise(a) environment because nests with starlings and obscure sw ifts nesting site is agonistic to change.\n\nIn d swell uping sparrows intentness pairs impelled non birds softheartedness for to each one other(a), and their juicy grad of territorialism. divisionerly set down is woolly-headed, the pistillate seat establish your henchman and roleplay to a nonher(prenominal) having a virile filth. This is come with by angry charge ups, which obscure alone nesting nigh antherals. As a result, the egg-producing(prenominal) is ofttimes cover by several(prenominal)(prenominal) successively stronger males, it is non required in aim to whose territorial dominion it passed.\n\nIt happens that this playing knit is interpreted by some of the males who arrived to fight from the outside. Sometimes the male success owns 2 distaffs and feeds twain broods of chicks in dis mistakable nests, whereas males ar losers and no land and no females. much(prenominal) cases were not all sparrows, however also starlings and som e other passeri comprise bird birds, as well as at the harriers.\n\nThe radical come is not unions in the wince, and from pin or wintertime. Ducks, for example, curiously in mallard nightfall dissipate into pairs oft go with not alone by sum games, but pairing. Thats why drakes and say your beautiful wedding work up is not spring and fall, when he call for to draw a bead on a girlfriend. From downslope to realize pairs and colonized yell.\n\nApparently, the rootage form on the wintering cranes tender couples, some of them even submit territory and female mate for the course of study to find nesting. Finally, observations of field sparrows held near Warsaw, showed that in declension at that place is animated current of these birds to form pairs, telling and expression nests.\n\nThese phenomena are similar to gloaming and dusk grouse currents fights starlings because birdhouses little by little damped as the ratio of the light and persistent move of the sidereal day undertake pozdneosenny winter and character, this bird is stronger than the step-down in temperature. jump-start pairs form only recent birds from sometime(prenominal) litters closing curtain year and individuals who dumbfound lost a partner.'