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
2012-03-23
26
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 presentday Somalia. Previously, scientists had thought humans first left via the Nile Valley or the Far East.
"Up fill 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 Tübingen 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. A. E. , 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“…though 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://kaotiyun.com/show/n1iO777K
0
专业英语八级
相关试题推荐
Humanrelationshavecommandedpeople’sattentionfromearlytimes.Thewaysofpeoplehavebeenrecordedininnumerablemyths,
Lastyear,whenPresidentGeorgeW.Bushannouncedthatfederalfundscouldbeusedtosupportresearchonhumanembryonicstem
In17th-centuryNewEngland,almosteveryonebelievedinwitches.Strugglingtosurviveinavastandsometimesunforgivingland
IsmailKadare,whowasrewardedtheManBooker【M1】______internationalprizeforliteraturethisyear,isthefirst
Videoconferencingisgraduallybecominganacceptedmeansinwhichtodobusiness.Foralongtimeissufferedfromtheimageo
OncefoundalmostentirelyinthewesternUnitedStatesandinAsia,dinosaurfossilsarenowbeingdiscoveredonallsevencont
AIDSisnottransmittedthroughroutine,nonintimatecontactinthehomeortheworkplace.Transmissionfromonepersontoanoth
"ShallIcomparetheetoasummer’sday?"ThisisthebeginninglineofoneofShakespeare’s______.
Theromanticimageofthetrustypostman,deliveringletterstothefarthest-flungcornersoftheland,makesthereformofpost
Whenmywife,Meg,sufferedaseverestrokethatimmobilizedherleftside,Iknewwewouldbefacingagruelingodysseyinvolvi
随机试题
当培养基内色氨酸浓度较大时,色氨酸操纵子处于_______。
某公司当前普通股股价为16元/股,每股筹资费用率为3%,其上年度支付的每股股利为2元、预计股利每年增长5%,今年的股利将于近期支付,则该公司留存收益资本成本是()。
在下列总需求的构成部分中,属于内生变量的有()。
怎样激发学生的学习动机?
请围绕“我的祖国”为大班幼儿设计主题活动,应包括三个子活动。 要求:设计一个具体的活动方案,包括活动的名称、目标、准备和主要环节。
下列关于《诗经》的表述,正确的是()。
(68):A collection of r61ated infOrmation,organized for easy retrieval.
下列给定程序中,函数fun的功能是:删除指针P所指字符串中的所有空白字符(包括制表符、回车符及换行符)。输入字符串时用“#”结束输入。请改正程序中的错误,使它能输出正确的结果。注意:不要改动main函数,不得增行或删行,也不得更改程序的结
Hesoonreceivedpromotion,forhissuperiorsrealizedthathewasamanofconsiderable______.
Thebacteriathatcauseacommonfood-borneillnessshowlowdrugresistanceinAustralia,unlikesimilarstrainsfromtheUnite
最新回复
(
0
)