A new study suggests that the close interspecies bond that exists between humans and dogs may extend 27 000 or even 40 000 years

admin2017-04-28  28

问题     A new study suggests that the close interspecies bond that exists between humans and dogs may extend 27 000 or even 40 000 years back. That’s a【C1】______jump from 11 000 to 16 000 years ago, when dogs were【C2】______thought to have split from their wolf ancestors.
    Led by Harvard research fellow Pontus Skoglun, the authors of the study【C3】______DNA belonging to a 35 000-year-old Siberian wolf specimen. Their genomic analysis led them to【C4】______that the wolf was part of a population "that diverged from the common ancestor of present-day wolves and dogs very close in time to the【C5】______of the domestic dog lineage," according to an abstract.
    That means domesticated dogs may have been hanging out with humans during that same era, more than 20 000 years ago. The【C6】______for this finding was the discovery of the ancient bone, the abstract notes: The researchers made these【C7】______based on a small piece of bone picked up during an expedition to the Taimyr Peninsula in Siberia. Initially, they didn’t realize the bone fragment came from a wolf at all; this was only【C8】______using a genetic test back in the laboratory. But wolves are common on the Taimyr Peninsula, and the bone could have easily【C9】______to a modern-day wolf. On a hunch, the researchers decided to radiocarbon date the bone anyway. It was only then that they realized what they had: a 35 000-year-old bone from an【C10】______Taimyr wolf.
    A)ancient F)discoveries K)inventions
    B)appearance G)dramatic L)preview
    C)belonged H)examined M)previously
    D)conclude I)impetus N)seldom
    E)determined J)increasingly O)sudden
【C4】

选项

答案D

解析
转载请注明原文地址:https://kaotiyun.com/show/dMi7777K
0

最新回复(0)