北美居民捕猎三文鱼的最早证据

北美居民捕猎三文鱼的最早证据

Researchers in Alaska have found the earliest known evidence that Ice Age humans in North America used salmon1 as a food source, according to a new paper published this week in the Proceedings2 of the National Academy of Sciences. The findings counter traditionally held beliefs that Ice Age Paleoindians were primarily big-game hunters. They are based on analysis of 11,500-year-old chum salmon bones found by University of Alaska Fairbanks anthropologist3 Ben Potter and colleagues at the Upward Sun River site in Interior Alaska. Excavation4 of the site has revealed human dwellings5, tools and human remains6, as well as the salmon bones.

"Salmon fishing has deep roots, and we now know that salmon have been consumed by North American humans at least 11,500 years ago," said lead author Carrin Halffman, a UAF anthropologist who helped analyze7 the fish bones with co-authors Brian Kemp of Washington State University, Potter and others.

The findings also suggest that salmon spawning8 runs were established much earlier and much farther north than previously9 thought, at the end of the Pleistocene epoch10, also known as the last Ice Age.

Ancient DNA11 and stable isotope12 analysis verified the fish remains as sea-run chum salmon that migrated upriver some 1,400 kilometers from where the mouth of the Yukon River now exists. These analyses indicate that modern salmon migrations13 may have ancient roots, dating back to at least the end of the last Ice Age.

"We have cases where salmon become landlocked and have very different isotopic14 signatures than marine15 salmon. Combining genetic16 and isotopic analyses allow us to confirm the identity as chum salmon, which inhabit the area today, as well as establish their life histories," said Potter. "Both are necessary to understand how humans used these resources."

1 salmon

n.鲑，大马哈鱼，橙红色的

参考例句：

We saw a salmon jumping in the waterfall there.我们看见一条大马哈鱼在那边瀑布中跳跃。

Do you have any fresh salmon in at the moment?现在有新鲜大马哈鱼卖吗？

2 proceedings

n.进程，过程，议程；诉讼(程序)；公报

参考例句：

He was released on bail pending committal proceedings. 他交保获释正在候审。

to initiate legal proceedings against sb 对某人提起诉讼

3 anthropologist

n.人类学家，人类学者

参考例句：

The lecturer is an anthropologist.这位讲师是人类学家。

The anthropologist unearthed the skull of an ancient human at the site.人类学家在这个遗址挖掘出那块古人类的颅骨。

4 excavation

n.挖掘，发掘；被挖掘之地

参考例句：

The bad weather has hung up the work of excavation.天气不好耽误了挖掘工作。

The excavation exposed some ancient ruins.这次挖掘暴露出一些古遗迹。

5 dwellings

n.住处，处所( dwelling的名词复数 )

参考例句：

The development will consist of 66 dwellings and a number of offices. 新建楼区将由66栋住房和一些办公用房组成。

The hovels which passed for dwellings are being pulled down. 过去用作住室的陋屋正在被拆除。 来自《简明英汉词典》

6 remains

n.剩余物，残留物；遗体，遗迹

参考例句：

He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。

The remains of the meal were fed to the dog.残羹剩饭喂狗了。

7 analyze

vt.分析，解析 (=analyse)

参考例句：

We should analyze the cause and effect of this event.我们应该分析这场事变的因果。

The teacher tried to analyze the cause of our failure.老师设法分析我们失败的原因。

8 spawning e223115a66b2213a16c438abb9a400cb

产卵

参考例句：

Encounter sites have a small chance of spawning a "Commander" NPC. 遭遇战地区有很小的几率遇到NPC指挥官。

Instantly revives your Champion at your Spawning Pool, 9 minute cooldown. 立即在出生地复活你的英雄，冷却时间9分钟。

9 previously

adv.以前，先前（地）

参考例句：

The bicycle tyre blew out at a previously damaged point.自行车胎在以前损坏过的地方又爆开了。

Let me digress for a moment and explain what had happened previously.让我岔开一会儿，解释原先发生了什么。

10 epoch

n.(新)时代；历元

参考例句：

The epoch of revolution creates great figures.革命时代造就伟大的人物。

We're at the end of the historical epoch,and at the dawn of another.我们正处在一个历史时代的末期，另一个历史时代的开端。

11 DNA 4u3z1l

(缩)deoxyribonucleic acid 脱氧核糖核酸

参考例句：

DNA is stored in the nucleus of a cell.脱氧核糖核酸储存于细胞的细胞核里。

Gene mutations are alterations in the DNA code.基因突变是指DNA密码的改变。

12 isotope

n.同位素

参考例句：

The isotope ratio is directly used for comparing oils or gases.同位素比率直接用于比较各种石油或天然气。

How to apply a radio isotope?如何运用放射性同位素？

13 migrations

n.迁移，移居( migration的名词复数 )

参考例句：

It foundered during the turmoils accompanying the Great Migrations. 它在随着民族大迁徙而出现的混乱中崩溃。 来自辞典例句

Birds also have built-in timepieces which send them off on fall and spring migrations. 鸟类也有天生的时间感应器指导它们秋春迁移。 来自互联网

14 isotopic

adj.同位素的，合痕的

参考例句：

The isotopic signatures of most ancient limestones indicated the same process. 大多数古代石灰岩的同位素特征说明了同样的过程。 来自辞典例句

Isotopic discrimination is not likely. 同位素甄别是不可能的。 来自辞典例句

15 marine

adj.海的；海生的；航海的；海事的；n.水兵

参考例句：

Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。

When the war broke out,he volunteered for the Marine Corps.战争爆发时，他自愿参加了海军陆战队。

16 genetic

adj.遗传的，遗传学的

参考例句：

It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。

Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。