In the 19th century, passenger pigeons A A. were common sightings B. suffered a lot from storms C. lived mainly in North America D. were the largest in American history6. What do we know about de-extinction?C A. It will change the DNA of the extinct animals. B. It was first used...
these animals no longer have a safe place to live(他相信使灭绝的动物复生对地球有害。这些动物不再有一个安全的地方生活).”和“they could cause other animals to die(它们会导致其他动物死亡)”可知,Stuart Primm反对灭绝物种复活是因为他认为这些复活的动物会造成一些其他的问题。故选B。 (4)题详解: ...
C. Pollution of rivers. D. Arrival of other wild animals.29. What does the underlined word “decimate” mean in the first paragraph?A. Acquire. B. Export.C. Destroy. D. Distribute.30. What is a direct result of the Act passed in 1934?A. The stamp price has gone down. ...
Rats and other animals need to be highly at tuned to social signals from others so that can identify friends to cooperate with and enemies to avoid.To find out if this extends to non-living beings,Loleh Quinn at the University of California,San Diego,and her colleagues tested whether rats ...
【小题1】In the 19th century, passenger pigeons ___. A.were common sightings B.suffered a lot from storms C.lived mainly in North America D.were the largest in American history【小题2】What do we know about deextinction? A.It will change the DNA of the extinct animals. B.It was...
(1)Inthe19thcentury,passengerpigeons ___.A.werecommonsightingsB.sufferedalotfromstormsC.livedmainlyinNorthAmericaD.werethelargestinAmericanhistory(2)Whatdoweknowaboutdeextinction? ___A.ItwillchangetheDNAoftheextinctanimals.B.Itwasfirstusedinpassengerpigeons.C.Itisdifficulttocarryout.D.Itprovedtobeuseful...
Animals live all over the world. T here are lots of animals in 26 .You can see elep hants and 27in the grassland(草地),ca mels in the desert,monkeys and snakes in the jungle(丛林).Lions are also African,and 28in countries like T anzania.T here are also elephants in 29 like T ...
Maximum Standing Height: ~ 2.3 meters / 7.6 feetAverage Standing Height: ~ 1.9 meters / 6.2 feetNatural habitat: Northern North America, Northern EuropeTallest sub-species: Alaskan Moose Moose come in ninth place among the tallest animals on Earth. They are the by far tallest deer and can re...
There was a time long ago when a land bridge connected Asia and North America. The first settlers in North America crossed this land bridge from what is now Siberia to Alaska. The people who made this initial crossing were probably following the animals they used for food. Finally, the ocea...
Previously, scientists had thought that growth lines showed up only on the bones of cold-blooded animals, since these animals grow in fits and starts. Warm-blooded animals, like mammals and birds, are assumed to grow continuously, because they keep their temperatures up and have high metabolic ...