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英语翻译符合初中难度

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英语翻译
符合初中难度
英语翻译符合初中难度
The panda is the main points of two kinds: sichuan panda (distributed in sichuan and gansu area panda species and distribution in qinling pandas (shaanxi qinling area)
Two subspecies in shape has already formed the obvious difference, by contrast, sichuan subspecies skull head big teeth small, small head teeth qinling subspecies, sichuan subspecies head length approximate bear, qinling subspecies head round more like the cat.In addition, both the pelage differences are also very outstanding, sichuan subspecies chest for deep black, abdomen is white and lower abdominal maojian tea black, white MAO gan ceaselessly, Qinling subspecies chest for dark brown, abdomen is brown, lower abdominal maojian tea brown, white MAO gan ceaselessly.
In nature, once found many with two or more forms of the same species, in the same habitat common perched phenomenon, science called species to two states phenomenon or polymorphism, also called two form sex or pleomorphism. For giant pandas to, not only now people in the field and in the zoo will see in the pandas for black and white body color, in our numerous ancient books and books described in the giant panda, colors are "black-and-white barge", the world's natural history museum has a collection of 600-700 pandas specimens, and various scientific papers and other texts mention on the giant pandas' coats are black and white. So do you have other colors pandas? In 1985, mar 26 in shaanxi qinling foping natural protection zones of elevation is about 1200 m a river valley, found only 1 critically ill pandas, body extremely weak, later after reserve of staff and all aspects of the effort to rescue, converting and recover after foster in xian zoo and named it "Daniel," at age 13, weight more than 60 kilograms. Unusually, Danny fur is black and white, but the brown and white. This is the world body hair is brown scientific first discovered the pandas, then in 1990 and in 1991, in foping nature reserve of bamboo forest and 2 times respectively observed brown pandas 1 only adult and 1 only cubs. According to live in qinling of an old hunter said he once back in 1954 is seen in the field with a coat of the same Daniel pandas. In addition, the others had also seen in the wild giant panda, 1 only brown adult and 1 only cubs. So, in the qinling probably always exist with two different colours of giant pandas, but brown pandas and is not an independent populations. Brown hair that scientists are many animals a primitive traits of performance, so in the qinling found body color is brown and white panda is probably a atavism.From April 1986, giant pandas Daniel estrus, respectively by using during freezing semen on artificial insemination and raised in foping nature reserve of male beast "curved" mating methods to make pregnancy, and in the same year on September 13 nissan under two young, but could not survive. In April 1989 and Danny again, again with curved estrus, mating, conception that after August 31 nissan under 1 female cub, after careful nursing, luckily survive, but growth compare logy, named it "qin qin". However, Daniel produce a cub's coat are black and white alternate with, and without any brown. At present, scientists to this kind of phenomenon there are some conjecture: the first kind think brown pandas appear may be due to the effect of trace elements synthesized hair pigment in the qinling area of soil and water content of abnormal, thus affecting its hair of melanin synthesis. But if it is for this reason that the area of the produce of the giant panda population seems to should have from black to brown colour changes of various tracheid, but so far has not yet found such intermediary type; The second think brown hair is due to genetic mutation caused, but because the genetic mutation in nature and the influence of the phenomenon to appear the probability of colour is very low, The third kind think this is a kind of recessive gene homozygous results, assuming that the color of one gene for the body hair to control, the control brown hair gene is recessive. Only when both parents are carrying the gene, they parent generation possible recessive gene homozygous, thus grow a brown hair. The third kind of explanation although seems more satisfactory, but because people have the relevant information is little, so to uncover brown pandas riddle remains to further research.熊猫中主要分两种:四川大熊猫(分布在四川和甘肃一带的大熊猫种群)和秦岭大熊猫(分布在陕西秦岭一带)
两个亚种在形态上已经形成了明显差异,通过头骨对比,四川亚种头大牙齿小,秦岭亚种头小牙齿大,四川亚种头长近似熊,秦岭亚种头圆更像猫.
此外,两者的毛色差异也很突出,四川亚种胸部为深黑色,腹部为白色,下腹部毛尖黑色,毛干为白色;秦岭亚种胸部为深棕色,腹部为棕色,下腹部毛尖棕色,毛干白色.
自然界中,曾经发现不少具有两种或两种以上形态的同一物种,在同一生境中共同栖息的现象,科学上称之为物种的二态现象或多态现象,也叫做二形性或多形性.对于大熊猫来说,不仅现在人们在野外和在动物园中所见到的大熊猫为黑白相间的体色,在我国众多的古籍和医书中所描写大熊猫的颜色都是“黑白驳”,世界各国的自然历史博物馆所收藏的600-700个大熊猫标本,以及各种科学论文和其他文献上提到的大熊猫的毛色也都是黑白相间的.那么有没有其他颜色的大熊猫呢?1985年3月26日,在陕西秦岭的佛坪自然保护区内一个海拔大约为1200米的河谷中,发现了1只患有重病的大熊猫,身体极度衰弱,后来经过保护区的工作人员和各个方面的协力抢救,才转危为安,病愈以后寄养在西安动物园,取名“丹丹”,当时年龄为13岁,体重60多千克.与众不同的是,丹丹的毛色并非黑白相间,而是棕色和白色相间.这是世界上科学界首次发现体毛为棕色的大熊猫,此后于1990年和1991年,在佛坪自然保护区内的竹林中又有2次分别观察到棕色大熊猫的1只成体和1只幼仔.据居住在秦岭的一位老猎人说,他曾经早在1954年就在野外见到过一只毛色与丹丹相同的大熊猫.此外,还有其他人也曾在野外见到过棕色大熊猫的1只成体和1只幼仔.所以,在秦岭很可能一直同时存在着具有两种不同毛色的大熊猫,但棕色大熊猫并不是一个独立的种群.棕色的体毛被科学家们认为是很多动物的一种原始性状的表现,那么在秦岭发现的体色为棕色与白色相间的大熊猫很可能是它的一种返祖现象.
1986年4月,大熊猫丹丹发情期间,分别通过利用冷冻精液进行人工授精和与饲养在佛坪自然保护区的雄兽“弯弯”交配的方法使之怀孕,并于当年9月13日产下2个幼仔,但都没有成活.1989年4月丹丹再次发情时,又与弯弯交配,受孕后于当年8月31日产下1个雌性幼仔,经过精心护理,幸运地存活下来,但生长发育比较迟缓,取名“秦秦”.不过,丹丹所生育的幼仔的毛色均为黑白相间,并没有任何棕色.目前,科学家对这种现象有下面几种推测:第一种认为棕色大熊猫的出现可能是由于影响毛发色素合成的微量元素在秦岭地区的土壤、水源中含量异常,因而影响它的毛发中的黑色素的合成.但如果是这个原因,该地区所产的大熊猫种群中似乎应该有从黑色到棕色变化的各种毛色的中间类型,但迄今为止尚未发现这样的居间类型;第二种认为棕色的体毛是由于基因突变所引起的,但在自然界由于基因突变而影响毛色的现象出现的概率很低;第三种认为这是一种隐性基因纯合的结果,假设体毛的颜色由一对基因来控制,则控制棕色体毛的基因为隐性.只有当亲本双方同时携带有这种基因的时候,它们的子一代才可能出现隐性基因纯合,从而生长出棕色的体毛.第三种解释虽然似乎比较圆满,但由于人们目前掌握的有关资料还很少,所以要揭开棕色大熊猫之谜还有待于进一步的研究.