首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
A period of climate change about 130,000 years ago would have made water travel easier by lowering sea levels and creating navig
A period of climate change about 130,000 years ago would have made water travel easier by lowering sea levels and creating navig
admin
2014-06-02
37
问题
A period of climate change about 130,000 years ago would have made water travel easier by lowering sea levels and creating navigable lakes and rivers in the Arabian Peninsula, the study says. Such a shift would have offered early modern humans—which arose in Africa about 200,000 years ago—a new route through the formerly scorching northern deserts into the Middle East. The new paper was spurred by the discovery of several 120,000-year-old tools at a desert archaeological site in the United Arab Emirates. The presence of the tools—whose design is uniquely African, experts say—so early in the region suggests early humans marched out of Africa into the Arabian Peninsula directly from the Horn of Africa, roughly present-day Somalia Previously, scientists had thought humans first left via the Nile Valley or the Far East.
"Up till now we thought of cultural developments leading to the opportunity of people to move out of Africa," said study co-author Hans-Peter Uerpmann, a retired archaeobiologist at the University of Tubingen in Germany. "Now we see, I think, that it was the environment that was the key to this," Uerpmann said during a press briefing Wednesday.
The discovery "leaves a lot of possibilities for human migrations, and keeping this in mind, might change our view completely." During the past few years, a series of tools were discovered at the Jebel Faya site in the U.AE., some of which—such as hand axes—had a two-sided appearance previously seen only in early Africa.
Scientists used luminescence dating to determine the age of sand grains buried with the stone tools. This technique measures naturally occurring radiation stored in the sand. For the climatic data, scientists studied the climate records of ancient lakes and rivers in cave stalagmites, as well as changes in the level of the Red Sea. This warmer period 130,000 years or so ago caused more rainfall on the Arabian Peninsula, turning it into a series of lush rivers that humans might have boated or rafted.
During this period the southern Red Sea’s levels dropped, offering a "brief window of time" for humans to easily cross the sea—which was then as little as 2.5 miles wide, according to Adrian Parker, a physical geographer from Oxford Brookes University in the United Kingdom.
Once humans entered the peninsula, they dispersed and likely reached the Jebel Faya site by about 125,000 years ago, according to the study, published in the journal Science.
Geneticist Spencer Wells called the discovery a "very interesting find," especially because the Arabian Peninsula is becoming a hot spot for archaeological finds—particularly underwater, since the Persian Gulf was a fertile river delta during early human migrations. But he noted that the study doesn’t "rewrite the book on what we know about human migratory history." That’s because tools dating to the same period have already been found in Israel, so it’s "consistent with what we suspected" about an earlier wave of migration into the Middle East, said Wells, director of the National Geographic Society’s Genographic Project. Wells also noted there’s no evidence yet that the migrants in the new paper were our ancestors—the group, and their genes, may have died out long ago.
Bence Viola, of the Max-Planck-Institute for Evolutionary Anthropology in Leipzig, Germany, agreed the finding was interesting but not that surprising, also citing the evidence of humans in Israel about 120,000 years ago. Viola, who wasn’t involved in the study, added that the migration route proposed in the paper makes sense on another level—the Arabian Peninsula would have been something early humans were used to. "If you look even today, the environment in the Horn of Africa, in Somalia or northern Ethiopia, is similar to what you see in Oman or Yemen—not like the big desert," Viola noted. "It’s not like they needed to adapt to a completely different environment—it’s an environment that they knew."
Why they made the trek is another question, since they wouldn’t have been hurting for food or resources in their African homeland, Viola noted. "Curiosity," he said, "is a pretty human desire."
The word "scorching" in the first paragraph means
选项
A、aboriginal.
B、primitive.
C、luxuriant.
D、baking-hot.
答案
D
解析
根据“…through the formerly scorching northern deserts...”可以确定,scorching应指“酷热的”,故正确答案是D项baking-hot(灸热的,极热的)。
转载请注明原文地址:https://jikaoti.com/ti/Kl0YFFFM
0
专业英语八级
相关试题推荐
BodySystemsAbodysystemreferstoagroupoforgans,whicharepartsofthebodythatdoaspecialjob,suchastheheart,
Clearlyifwearetoparticipateinthesocietyinwhichwelivewemustcommunicatewiththeotherpeople.Agreatdealofcomm
WinstonChurchillChurchillcamefromamilitaryfamilyandenteredthearmyasacavalryofficer.Between1895and1898he
WinstonChurchillChurchillcamefromamilitaryfamilyandenteredthearmyasacavalryofficer.Between1895and1898he
WhichofthefollowingstatementsisINCORRECT?
Eliotwaswrappedupin______whenhebegantowritepoems.WhichofthefollowingstatementisNOTtrueofEliot’sfirstpoem?
UniversityAwardsTheBA(orBachelorofArts)andtheBSc(orBachelorofScience)arealsocalled"【1】".SomeBritishunive
愚人买鞋从前有个愚人,有一天想上市去买双新鞋。他便先用尺子把脚量了量。拿了根稻秆,记下尺码。可是因为急于赶路,把稻秆忘在家里了。他来到市上,找到了卖鞋的摊子,摸了摸口袋,记尺码的稻秆不见了,就对卖鞋的说:“尺码忘在家里了,不晓得大小,让我回家拿尺
Inanefforttoproducethelargest,fastest,andmostluxuriousshipfloat,theBritishbuilttheTitanic.Itwassosuperiort
ThroughhisfamouscharacterHamletShakespearesaid,"tobeornottobe,thatisaquestion."Forhundredsofyears,peopleha
随机试题
考生文件夹下存在一个数据库文件“samp3.accdb”,里面已经设计了表对象“tEmp”、窗体对象“fEmp”、报表对象“rEmp”和宏对象“mEmp”。同时,给出窗体对象“fEmp”的若干事件代码,试按以下功能要求补充设计。功能:在窗体加载事件中
香农—威纳多样性指数包含两个因素,即()。
A.实行集中挂网,由医院直接采购B.实行双信封制公开招标采购C.按国家现行规定采购D.采取公开透明、多方参与的价格谈判机制国家要求公立医院实行药品分类采购对寄生虫病和防治传染病的免费用药可以
节税与风险并存,节税越多的方案往往也是风险()的方案,两者的权衡取决于多种因素,包括客户对风险的态度这个因素。
苗族青年男女向对方表达心意、显示才能的一种古老的对歌方式是()。
下列哪个图形的特征有别于其他三个图形?
下列说法正确的是()。
某机主存容量为1MB,两路组相连方式(每组仅有两块)的Cache容量为64KB,每个数据块为256字节。CPU要顺序访问的地址为20124H、58100H、60140H和60138H等4个主存字节单元中的数。已知访问开始前第2组(组号为1)的地址阵
OfficeWorks544HudsonStreetBoston,MA34602Tel:
A、15minutes.B、45minutes.C、7minutes.D、8minutes.A重点在于时间上。一定要抓住两个时间“at9:00o’clock”和“nowit’s8:45.”,然后进行比较,作减法得出时间差。
最新回复
(
0
)