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■ The tree swallow(Tachycineta bicolor)
■ The tree swallow(Tachycineta bicolor)
https://en.wikipedia.org/wiki/Tree_swallow
The tree swallow (Tachycineta bicolor) is a migratory bird of the family Hirundinidae. Found in the Americas, the tree swallow was first described in 1807 by French ornithologist Louis Vieillot as Hirundo bicolor. It has since been moved to its current genus, Tachycineta, within which its phylogenetic placement is debated. The tree swallow has glossy blue-green upperparts, with the exception of the blackish wings and tail, and white underparts. The bill is black, the eyes dark brown, and the legs and feet pale brown. The female is generally duller than the male, and the first-year female has mostly brown upperparts, with some blue feathers. Juveniles have brown upperparts, and a grey-brown-washed breast. The tree swallow breeds in the US and Canada. It winters along southern US coasts south, along the Gulf Coast, to Panama and the northwestern coast of South America, and in the West Indies.
The tree swallow nests either in isolated pairs or loose groups, in both natural and artificial cavities. Breeding can start as soon as early May, although this date is occurring earlier because of climate change, and it can end as late as July. This bird is generally socially monogamous (although about 8% of males are polygynous), with high levels of extra-pair paternity. This can benefit the male, but since the female controls copulation, the lack of resolution on how this behaviour benefits females makes the high level of extra-pair paternity puzzling. The female incubates the clutch of two to eight (but usually four to seven) pure white eggs for around 14 to 15 days. The chicks hatch slightly asynchronously, allowing the female to prioritize which chicks to feed in times of food shortage. They generally fledge about 18 to 22 days after hatching. The tree swallow is sometimes considered a model organism, due to the large amount of research done on it.
An aerial insectivore, the tree swallow forages both alone and in groups, eating mostly insects, in addition to molluscs, spiders, and fruit. The nestlings, like the adult, primarily eat insects, fed to it by both sexes. This swallow is vulnerable to parasites, but, when on nestlings, these do little damage. The effect of disease can become stronger as a tree swallow gets older, as some parts of the immune system decline with age. Acquired T cell-mediated immunity, for example, decreases with age, whereas both innate and acquired humoral immunity do not. Because of its large range and stable population, the tree swallow is considered to be least concern by the International Union for Conservation of Nature. In the US, it is protected by the Migratory Bird Treaty Act of 1918, and in Canada by the Migratory Birds Convention Act. This swallow is negatively affected by human activities, such as the clearing of forests; acidified lakes can force a breeding tree swallow to go long distances to find calcium-rich food items to feed to its chicks.
Taxonomy and etymology
The tree swallow was described as Hirundo bicolor by Louis Pierre Vieillot in his Histoire naturelle des oiseaux de l'Amérique Septentrionale, published in 1807.[2] It was then placed in its current genus Tachycineta when Jean Cabanis established it in 1850.[3] In 1878, Elliott Coues suggested that the tree swallow, at the very least, be put in its own subgenus, Iridoprocne, on the basis of its plumage, along with the white-winged swallow, Chilean swallow, white-rumped swallow, and mangrove swallow.[4] By 1882, he had upgraded this to a full genus.[5] Some authors continued to use this classification, with the addition of Tumbes swallow; however, genetic evidence supports the existence of a single genus, Tachycineta. The tree swallow is also called the white-bellied swallow for its white underparts.
The generally accepted genus name is from Ancient Greek takhykinetos, "moving quickly", and the specific bicolor is Latin and means "two-coloured".[8] The other genus name, Iridoprocne, comes from the Greek iris, meaning rainbow, and Procne, a figure who supposedly turned into a swallow.
How exactly the tree swallow is related to other members of Tachycineta is unresolved. In studies based on mitochondrial DNA, it was placed basal (meaning it was the first offshoot in the species tree) within the North American-Caribbean clade consisting of the violet-green swallow, golden swallow, and Bahama swallow.[9][10] Although mitochondrial DNA is advocated as a better indicator of evolutionary changes because it evolves quickly, analyses based on it can suffer because it is only inherited from the mother, making it worse than nuclear DNA from multiple loci at representing the phylogeny of a whole group.[11] A study based on such nuclear DNA placed the tree swallow in the most basal position within Tachycineta as a whole (as a sister group to the rest of the genus).
The tree swallow has a length between about 12 and 14 cm (4.7 and 5.5 in) and a weight of approximately 17 to 25.5 g (0.60 to 0.90 oz). Wingspan ranges from 11.8 to 13.8 in (30-35 cm).[13] The male has mostly glossy blue-green upperparts, the wings and tail being blackish. The underparts[14] and the cheek patch are white,[7] although the underwing coverts are grey-brown.[14] The bill is black, the eyes dark brown, and the legs and feet pale brown.[7] The female is duller in colour than the male, and sometimes has a brown forehead.[14] The second-year[note 1] female also has brown upperparts, with a variable number of blue feathers; some third-year females also retain a portion of this subadult plumage.[15] According to a 1987 study, this likely allows a younger female to explore nest sites, as the resident male is usually less aggressive to a subadult female.[16] A 2013 study found that the resident female was less aggressive towards second-year female models when they were presented separately from older models. Why the female eventually replaces its subadult plumage is unknown; it may allow males to assess female quality, as pairs mate assortatively based on plumage brightness.[17] The juvenile tree swallow can be distinguished by its brown upperparts and grey-brown-washed breast.
※ From Wikipedia(자료 출처 : 위키 백과)
■ 人生(인생)
人生事(인생사) 先後(선후) 緩急(완급) 輕重(경중)이 있습니다.
우리네 人生(인생)은 아무도 대신 살아 주거나 누구도 대신 아파 주거나 죽어 줄 수가 없는 것입니다.
어디든지 갈 수 있을 때 가지 않으면 가고 싶을 때 갈 수가 없고 무엇이든지 할 수 있을 때 하지 않으면 하고 싶을 때 할 수가 없는 것입니다.
奇跡(기적)은 아무에게나 어디서나 함부로 일어나지 않습니다.
우리가 어릴 때는 꿈과 희망을 먹고 자랐지만 성인이 되면 計劃(계획)과 實踐(실천) 만이 존재할 뿐입니다.
마음 가는 대로 잘 생각하고 判斷(판단)해서 몸 가는 대로 行動(행동) 하고 實踐(실천)하며 하고 싶은 대로 하고 살면 될 것입니다.
다만, 嚴重(엄중)한 現實(현실)앞에 우선순위를 어디에 어떻게 둘 것인가에 愼重(신중)을 기해서 責任(책임)과 義務(의무)를 다해야 할 것입니다.
人生事(인생사) 刹那(찰나)와 彈指(탄지)에 지나지 않습니다.
지금 이 순간, 最善(최선)입니까?
인생의 眞理(진리)는 오직 살아 있어야 되는 것입니다.
그러기 위해서는 오로지 건강하세요.
가족의 健康(건강)과 가정의 幸福(행복)을 축원합니다.
늘 고맙습니다.
19991212(陰1105) SUN
Mundy Sung
■ 生活사진
생활寫眞은 일상의 사소한 발견입니다.
삼라만상(森羅萬象)은 곧 사진의 훌륭한 소재라고 생각합니다.
늘 가지고 다니는 휴대 전화기나 손 안에 쏙 들어가는 똑따기 사진기만으로도 누구나 크게 공감하고 많이 동감하는 이야기를 만들 수가 있을 것이라 믿습니다.
더 없는 사랑과 꾸밈없는 정성으로 인시공(人時空)을 담아내어 소중한 추억으로 오래토록 간직하게 되기를 희망합니다.
‘사진은 빛의 예술이자 역사의 기록이다’
생활寫眞에 대하여 이렇게 거창한 말까지 앞세울 필요는 전혀 없을 것 같습니다.
진실과 진심으로 있는 대로 보고 진정과 최선을 다하여 보이는 대로 담아내면 그것이 곧 예술이자 역사가 될 것입니다.
보다 많은 사진 인구의 저변 확대를 기대합니다.
가족의 건강과 가정의 행복을 祝願(축원)합니다.
오로지 건강하세요.
늘 고맙습니다.
20121212(陰1029) WED
Mundy Sung
■ CAMERA : SONY DSC-HX90V(똑따기 사진기)
■ The tree swallow(Tachycineta bicolor)
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