【英语时差8,16】鸟类荷尔蒙映射其生活策略2

 Researchers wondered if corticosteroid variability was somehow related to life strategies. Would birds like the short lived great Tit, which lays twelve eggs at a time, have different hormone¹ levels than the Spotted² Ant bird which lays only two eggs and lives as long as eighteen years? Researchers collected blood samples from many bird species in North America and Panama, and used additional research data to compare corticosteroid levels to life strategies. They measured both baseline and stress induced hormone levels, and found that species with long life spans had lower baseline hormone levels, but higher stress induced levels than short lived species. Scientists think there is a physiological³ reason for this. Hormone levels are costly⁴ to maintain. The “hares” of the bird world pay that cost because they have few chances to have offspring. They can’t afford to make a mistake. The “tortoises”, on the other hand, have more breeding time and don’t need to keep their hormones⁵ on alert continuously. Instead, they wait until the threat is present and then ramp⁶ up their hormone levels. It’s all a matter of strategy.

1 hormone   

n.荷尔蒙，激素，内分泌

参考例句：

• Hormone implants are used as growth boosters.激素植入物被用作生长辅助剂。
• This hormone interacts closely with other hormones in the body.这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。

2 spotted   

adj.有斑点的，斑纹的，弄污了的

参考例句：

• The milkman selected the spotted cows,from among a herd of two hundred.牛奶商从一群200头牛中选出有斑点的牛。
• Sam's shop stocks short spotted socks.山姆的商店屯积了有斑点的短袜。

3 physiological   

adj.生理学的，生理学上的

参考例句：

• He bought a physiological book.他买了一本生理学方面的书。
• Every individual has a physiological requirement for each nutrient.每个人对每种营养成分都有一种生理上的需要。

4 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。

5 hormones   

n. 荷尔蒙，激素 名词hormone的复数形式

参考例句：

• This hormone interacts closely with other hormones in the body. 这种荷尔蒙与体內其他荷尔蒙紧密地相互作用。
• The adrenals produce a large per cent of a man's sex hormones. 肾上腺分泌人体的大部分性激素。

6 ramp   

n.暴怒，斜坡，坡道；vi.作恐吓姿势，暴怒，加速；vt.加速

参考例句：

• That driver drove the car up the ramp.那司机将车开上了斜坡。
• The factory don't have that capacity to ramp up.这家工厂没有能力加速生产。