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 amphibians 1 developed the ability to jump before they had mastered landing
You’d think an animal that hops 2 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 gracefully 3 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 physiology 5, to two more modern frog species. Unlike their more graceful 4 cousins, the primitive 6 frogs kept their back legs straight out after they jumped. So they don’t land on their feet. Instead, they do an ungainly belly 7 flop 8, 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
- 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。
- 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。
- 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。
- 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。
- 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。
- 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。
- The boss has a large belly.老板大腹便便。
- His eyes are bigger than his belly.他眼馋肚饱。