Earth and Sky:Spider Widows 蜘蛛寡妇

Spider Widows 蜘蛛寡妇

Spiders give many of us the shivers, though they usually leave people alone. Sometimes these spectacular predators¹ instead prey² on each other. Learn more about when spiders serve themselves as dinner -- today on Earth and Sky.

JB: This is Earth and Sky. We recently visited the Austin Children's Museum in Texas to record your science questions. Here's one from Ben Rosselet.

Ben Rosselet: Why does a black widow kill its husband after it helps make babies?

DB: Ben, another way to think of this is to ask, "Why do some males allow themselves to be killed by females?" Some scientists think it's common for female spiders to try to eat males either before or after mating. Since spiders are zealous³ predators, females might unintentionally prey on males .

JB: Then there's the Australian red back widow -- a species of black widow. Dr. Maydianne Andrade of the University of Toronto at Scarborough found that males only have a slim chance of finding future mates, and about 80% perish unsuccessfully in the process. Indeed, it's so critical for them to mate with the first female they encounter, that males have actually evolved self-sacrifice behaviors.

DB: After mating begins, the male red back somersaults around, launching his tasty abdomen⁴ directly into the jaws⁵ of the female. Meanwhile, as he's being eaten, he fertilizes⁶ the female.

DB: It turns out that for the Australian red back widow, males that are wholly consumed are more successful at mating and father more baby spiders than those that aren't. And that's our show for today. With thanks to the National Science Foundation, we're Block and Byrd for Earth and Sky.

1 predators   

n.食肉动物( predator的名词复数 )；奴役他人者（尤指在财务或性关系方面）

参考例句：

• birds and their earthbound predators 鸟和地面上捕食它们的动物
• The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》

2 prey   

n.被掠食者，牺牲者，掠食；v.捕食，掠夺，折磨

参考例句：

• Stronger animals prey on weaker ones.弱肉强食。
• The lion was hunting for its prey.狮子在寻找猎物。

3 zealous   

adj.狂热的，热心的

参考例句：

• She made zealous efforts to clean up the classroom.她非常热心地努力清扫教室。
• She is a zealous supporter of our cause.她是我们事业的热心支持者。

4 abdomen   

n.腹，下腹(胸部到腿部的部分)

参考例句：

• How to know to there is ascarid inside abdomen?怎样知道肚子里面有蛔虫？
• He was anxious about an off-and-on pain the abdomen.他因时隐时现的腹痛而焦虑。

5 jaws   

n.口部；嘴

参考例句：

• The antelope could not escape the crocodile's gaping jaws. 那只羚羊无法从鱷鱼张开的大口中逃脱。
• The scored jaws of a vise help it bite the work. 台钳上有刻痕的虎钳牙帮助它紧咬住工件。

6 fertilizes   

n.施肥( fertilize的名词复数 )v.施肥( fertilize的第三人称单数 )

参考例句：

• The male sperm fertilizes the female egg. 雄性的精子使雌性的卵子受精。 来自辞典例句
• When the male reproductive cell fertilizes the female reproductive cell a zygote is formed. 当男性生殖细胞与女性生殖细胞发生受精时，就形成了一个合子。 来自辞典例句