原来青蛙还不会落地就先学会了跳跃(有声)

Frogs from an ancient lineage reveal that the amphibians¹ developed the ability to jump before they had mastered landing

You’d think an animal that hops² would know how to land. But for a kind of frog, that’s not the case. Imagine trying to catch a frog. You reach and they jump, only to land gracefully³ on their feet a few feet away.

It was thought that all frogs moved this way. They'd push off with their back legs, and then once in flight, rotate the limbs forward. Then they landed fore-limbs first. But researchers compared frogs of the family Leiopelmatidae, which still sport an ancient physiology⁵, to two more modern frog species. Unlike their more graceful⁴ cousins, the primitive⁶ frogs kept their back legs straight out after they jumped. So they don’t land on their feet. Instead, they do an ungainly belly⁷ flop⁸, and then struggle to get to their feet and jump again. The finding is in the journal Naturwissenschaften.

The scientists say that the back-leg push-off must have evolved first, with the ability to rotate and land softly evolving later. Although the bad landers are still around, their more controlled relatives appear to be better at making longer trips, foraging for food and, most importantly, avoiding other animals that have an interest in frog legs—for dinner
 

1 amphibians   

两栖动物( amphibian的名词复数 )； 水陆两用车； 水旱两生植物； 水陆两用飞行器

参考例句：

• The skin of amphibians is permeable to water. 两栖动物的皮肤是透水的。
• Two amphibians ferry them out over the sands. 两辆水陆两用车把他们渡过沙滩。

2 hops   

跳上[下]( hop的第三人称单数 )； 单足蹦跳； 齐足（或双足）跳行； 摘葎草花

参考例句：

• The sparrow crossed the lawn in a series of hops. 那麻雀一蹦一跳地穿过草坪。
• It is brewed from malt and hops. 它用麦精和蛇麻草酿成。

3 gracefully   

ad.大大方方地；优美地

参考例句：

• She sank gracefully down onto a cushion at his feet. 她优雅地坐到他脚旁的垫子上。
• The new coats blouse gracefully above the hip line. 新外套在臀围线上优美地打着褶皱。

4 graceful   

adj.优美的，优雅的；得体的

参考例句：

• His movements on the parallel bars were very graceful.他的双杠动作可帅了!
• The ballet dancer is so graceful.芭蕾舞演员的姿态是如此的优美。

5 physiology   

n.生理学，生理机能

参考例句：

• He bought a book about physiology.他买了一本生理学方面的书。
• He was awarded the Nobel Prize for achievements in physiology.他因生理学方面的建树而被授予诺贝尔奖。

6 primitive   

adj.原始的；简单的；n.原(始)人，原始事物

参考例句：

• It is a primitive instinct to flee a place of danger.逃离危险的地方是一种原始本能。
• His book describes the march of the civilization of a primitive society.他的著作描述了一个原始社会的开化过程。

7 belly   

n.肚子，腹部；(像肚子一样)鼓起的部分，膛

参考例句：

• The boss has a large belly.老板大腹便便。
• His eyes are bigger than his belly.他眼馋肚饱。

8 flop   

n.失败(者)，扑通一声；vi.笨重地行动，沉重地落下

参考例句：

• The fish gave a flop and landed back in the water.鱼扑通一声又跳回水里。
• The marketing campaign was a flop.The product didn't sell.市场宣传彻底失败，产品卖不出去。