SSS 2009-08-24
时间：2018-12-24 作者：英语课 分类：Scientific American(八)月
Two years ago, Duke University Medical Center researchers said that the supposedly useless appendix is actually where good gut 1 bacteria safely hide out during some unpleasant intestinal 2 conditions.
Now the research team has looked at the appendix over evolutionary 3 history. They found that animals have had appendixes for about 80 million years. And the organ has evolved separately at least twice, once among the weird 4 Australian marsupials and another time in the regular old mammal lineage that we belong to.
Darwin thought that only a few animals have an appendix and that the human version was what was left of a digestive organ called the cecum. But the new study found that 70 percent of rodent 5 and primate 6 groups have species with an appendix. And some living animals have a cecum and an appendix. If Darwin had known about species that had both organs, he probably would have revised his views of the appendix, the researchers note.
Ironically, it’s natural selection that keeps the human appendix from shrinking away completely. Because smaller ones are more likely to become infected. And keep your genes 7 out of the pool.
—Steve Mirsky
- It is not always necessary to gut the fish prior to freezing.冷冻鱼之前并不总是需要先把内脏掏空。
- My immediate gut feeling was to refuse.我本能的直接反应是拒绝。
- A few other conditions are in high intestinal obstruction. 其它少数情况是高位肠梗阻。 来自辞典例句
- This complication has occasionally occurred following the use of intestinal antiseptics. 这种并发症偶而发生在使用肠道抗菌剂上。 来自辞典例句
- Life has its own evolutionary process.生命有其自身的进化过程。
- These are fascinating questions to be resolved by the evolutionary studies of plants.这些十分吸引人的问题将在研究植物进化过程中得以解决。
- From his weird behaviour,he seems a bit of an oddity.从他不寻常的行为看来，他好像有点怪。
- His weird clothes really gas me.他的怪衣裳简直笑死人。
- When there is a full moon,this nocturnal rodent is careful to stay in its burrow.月圆之夜，这种夜间活动的啮齿类动物会小心地呆在地洞里不出来。
- This small rodent can scoop out a long,narrow tunnel in a very short time.这种小啮齿动物能在很短的时间里挖出一条又长又窄的地道来。