晚育趋势将使女性生育年龄增大
文章来源:未知 文章作者:meng 发布时间:2010-07-31 02:00 字体: [ ]  进入论坛
(单词翻译:双击或拖选)

The fashion for having children later in life could lead to women becoming more fertile in their 40s and beyond, scientists have suggested.

科学家指出,现在的晚育趋势将让未来女性40岁以后的生育能力增强。

As many women wait until they are older to give birth, only those with longer lasting1 fertility(多产,肥沃) genes2 will be successful.

That means the average length of fertility will grow as their genes will be passed on to their children.

The study from the University of Sheffield shows that previously3 women would marry early and if widowed were too old to remarry thus favouring early childbirth in women.

But today's reluctance5(勉强,不情愿) to settle down and reproduce until later in life could lead to fertility beginning to favour older women.

The researchers studied marriage patterns to trace the survival and marriage histories of 1,591 women.

Using 18th and 19th century Finnish records – a time when almost everyone got married and divorce was strictly6 forbidden.

They found that women aged7 30 to 35 were the most likely to be married. Those that wed4 wealthy husbands were married at a younger age but to relatively8 older men, meaning family sizes were bigger but with an increased risk of widowhood.

The researchers say that this high chance of widowhood, coupled with low remarriage prospects9 for older widows with children, limited the percentage of women in the population with the opportunity to reproduce at older ages.

Duncan Gillespie, from the university's Department of Animal and Plant Sciences said that in today's society however, women do not start childbearing(分娩,生子) until an older age as marriage is often delayed.

He said: "As a result of this, the natural selection maintaining young-age fertility might weaken and the relative strength of natural selection on old-age fertility could increase, something that could potentially lead to improvements in old-age fertility over many generations.”



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1 lasting IpCz02     
adj.永久的,永恒的;vbl.持续,维持
参考例句:
  • The lasting war debased the value of the dollar.持久的战争使美元贬值。
  • We hope for a lasting settlement of all these troubles.我们希望这些纠纷能获得永久的解决。
2 genes 01914f8eac35d7e14afa065217edd8c0     
n.基因( gene的名词复数 )
参考例句:
  • You have good genes from your parents, so you should live a long time. 你从父母那儿获得优良的基因,所以能够活得很长。 来自《简明英汉词典》
  • Differences will help to reveal the functions of the genes. 它们间的差异将会帮助我们揭开基因多种功能。 来自英汉非文学 - 生命科学 - 生物技术的世纪
3 previously bkzzzC     
adv.以前,先前(地)
参考例句:
  • The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。
  • Let me digress for a moment and explain what had happened previously.让我岔开一会儿,解释原先发生了什么。
4 wed MgFwc     
v.娶,嫁,与…结婚
参考例句:
  • The couple eventually wed after three year engagement.这对夫妇在订婚三年后终于结婚了。
  • The prince was very determined to wed one of the king's daughters.王子下定决心要娶国王的其中一位女儿。
5 reluctance 8VRx8     
n.厌恶,讨厌,勉强,不情愿
参考例句:
  • The police released Andrew with reluctance.警方勉强把安德鲁放走了。
  • He showed the greatest reluctance to make a reply.他表示很不愿意答复。
6 strictly GtNwe     
adv.严厉地,严格地;严密地
参考例句:
  • His doctor is dieting him strictly.他的医生严格规定他的饮食。
  • The guests were seated strictly in order of precedence.客人严格按照地位高低就座。
7 aged 6zWzdI     
adj.年老的,陈年的
参考例句:
  • He had put on weight and aged a little.他胖了,也老点了。
  • He is aged,but his memory is still good.他已年老,然而记忆力还好。
8 relatively bkqzS3     
adv.比较...地,相对地
参考例句:
  • The rabbit is a relatively recent introduction in Australia.兔子是相对较新引入澳大利亚的物种。
  • The operation was relatively painless.手术相对来说不痛。
9 prospects fkVzpY     
n.希望,前途(恒为复数)
参考例句:
  • There is a mood of pessimism in the company about future job prospects. 公司中有一种对工作前景悲观的情绪。
  • They are less sanguine about the company's long-term prospects. 他们对公司的远景不那么乐观。
TAG标签: children women genes fertile
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