揽瓜阁俱乐部第三期 Day14 2020.08.02
【人文科学-考古】 Clues to the earliest known bow-and-arrow hunting outside Africa have been found （672字 精读 必做篇）
People hunted with bows and arrows in a rainforest on a South Asian island starting around 48,000 years ago, a new study suggests.
Small bone artifacts with sharpened tips unearthed in a Sri Lankan cave represent the earliest evidence of bow-and-arrow use outside Africa, says a team led by archaeologist Michelle Langley of Griffith University in Brisbane, Australia.
Microscopic analyses of 130 of those bone points revealed surface cracks and other damage caused by high-speed impacts, likely because these artifacts were used as arrowheads, Langley and her colleagues conclude June 12 in Science Advances. Notches and wear at the bottom of the bone points indicate that they were attached to thin shafts. But the finds, from sediment in Fa-Hien Lena cave dating to between 48,000 and 34,000 years ago, are too short and heavy to have served as tips of blowgun darts, the investigators contend. Bow-and-arrow hunting at the Sri Lankan site likely focused on monkeys and smaller animals, such as squirrels, Langley says. Remains of these creatures were found in the same sediment as the bone points.
Evidence increasingly points to hunting with bows and arrows in Africa more than 60,000 years ago, says Marlize Lombard, an archaeologist at the University of Johannesburg who wasn't involved in the study. “I would not be surprised to see [bow-and-arrow] hunting associated with any Homo sapiens group after about 65,000 years ago, regardless of location,” Lombard says.
Lombard, however, reserves judgment on the Sri Lankan bone points until high-resolution CT scans are used to probe for damage from high-speed impacts inside the artifacts. That technique helped to determine that a more than 60,000-year-old bone point previously unearthed in South Africa was probably an arrowhead, a team including Lombard reported in the May 15 Quaternary Science Reviews.
Archaeologist Ryan Rabett of Queen's University Belfast in Northern Ireland calls the new study of Sri Lankan bone points “suggestive but not definitive” evidence of bow-and-arrow hunting. It's possible, he says, that bone points were attached to multi-pronged spears that were thrown or thrust at fish. Remains of fish were also found in ancient Fa-Hien Lena sediment.
Losing arrows while hunting in dense Sri Lankan forests would have presented a major challenge to ancient people, Rabett adds.
Other finds in Fa-Hien Lena cave, including bone implements possibly used to make clothes and nets as well as shell beads, indicate that a distinctive set of complex behaviors emerged deep in the Stone Age as people reached densely forested parts of South Asia, Langley and her colleagues say. A couple of pointed bones display no signs of having been attached to a shaft and possibly held bait while fishing or functioned as barbs in netted animal traps, Langley says. Another 29 bone artifacts appear to have been used to make clothes or nets out of animal skins or plant fibers.
Evidence of symbolic behavior at the site comes from three beads made from seashells and another three beads fashioned out of pieces of a red pigment called ochre. Single-holed ochre pieces might have been strung together as way to store them for future use rather than as ornaments, Langley says. Excavated chunks of red, yellow and silver pigment were likely used to decorate bodies or objects, she adds.
The artifacts support the idea, based mainly on archaeological finds in Africa, that complex behavior equivalent to that of people today emerged early in Homo sapiens evolution, 100,000 years ago or more, and involved finding ways to thrive in novel environments, Langley argues. What human evolution researchers often refer to as “modern” behavior “is all about flexibility and adaptability to a wide range of situations,” she says.
Until hominid fossils are found at Fa-Hien Lena, it's hard to say who occupied the site, says New York University archaeologist Justin Pargeter. H. sapiens, Neandertals and Denisovans inhabited parts of Asia and some Pacific islands, and periodically interbred, when bone points were being made at Fa-Hien Lena. “It may be too soon to conclude that this story is all about ‘modern' humans,” Pargeter says.
Source: Science News
【人文科学-心理】 The psychology behind irrational decisions （639字 4分23秒 听力 必做篇）
先做听力再核对原文哦~
听力视频下载链接及提取码：
链接：https://pan.baidu.com/s/14-NRxoRGi7IAhYRR_XsBJw
提取码：bsm4
Let's say you're on a game show. You've already earned $1000 in the first round when you land on the bonus space. Now, you have a choice. You can either take a $500 bonus guaranteed or you can flip a coin.
If it's heads, you win $1000 bonus. If it's tails, you get no bonus at all. In the second round, you've earned $2000 when you land on the penalty space. Now you have another choice. You can either take a $500 loss, or try your luck at the coin flip. If it's heads, you lose nothing, but if it's tails, you lose $1000 instead. If you're like most people, you probably chose to take the guaranteed bonus in the first round and flip the coin in the second round. But if you think about it, this makes no sense. The odds and outcomes in both rounds are exactly the same.
So why does the second round seem much scarier? The answer lies in a phenomenon known as loss aversion. Under rational economic theory, our decisions should follow a simple mathematical equation that weighs the level of risk against the amount at stake. But studies have found that for many people, the negative psychological impact we feel from losing something is about twice as strong as the positive impact of gaining the same thing. Loss aversion is one cognitive bias that arises from heuristics, problem-solving approaches based on previous experience and intuition rather than careful analysis.
And these mental shortcuts can lead to irrational decisions, not like falling in love or bungee jumping off a cliff, but logical fallacies that can easily be proven wrong. Situations involving probability are notoriously bad for applying heuristics. For instance, say you were to roll a die with four green faces and two red faces twenty times. You can choose one of the following sequences of rolls, and if it shows up, you'll win $25. Which would you pick? In one study, 65% of the participants who were all college students chose sequence B even though A is shorter and contained within B, in other words, more likely.
This is what's called a conjunction fallacy. Here, we expect to see more green rolls, so our brains can trick us into picking the less likely option. Heuristics are also terrible at dealing with numbers in general. In one example, students were split into two groups. The first group was asked whether Mahatma Gandhi died before or after age 9, while the second was asked whether he died before or after age 140. Both numbers were obviously way off, but when the students were then asked to guess the actual age at which he died, the first group's answers averaged to 50 while the second group's averaged to 67.
Even though the clearly wrong information in the initial questions should have been irrelevant, it still affected the students' estimates. This is an example of the anchoring effect, and it's often used in marketing and negotiations to raise the prices that people are willing to pay. So, if heuristics lead to all these wrong decisions, why do we even have them? Well, because they can be quite effective. For most of human history, survival depended on making quick decisions with limited information. When there's no time to logically analyze all the possibilities, heuristics can sometimes save our lives.
But today's environment requires far more complex decision-making, and these decisions are more biased by unconscious factors than we think, affecting everything from health and education to finance and criminal justice. We can't just shut off our brain's heuristics, but we can learn to be aware of them.
When you come to a situation involving numbers, probability, or multiple details, pause for a second and consider that the intuitive answer might not be the right one after all.
Source: TED
【笔记格式要求】
精读笔记格式要求： 1.总结文章中心大意 2.总结分论点或每段段落大意 3.摘抄印象深刻或者觉得优美的句子 4.总结文章中的生词 5.记录阅读时间、总结时间、总时间
精听笔记格式要求： 1.逐句听写整篇文章 2.对照原文修改听写稿，标记出错原因 3.总结文章中心大意 4.总结精听过程中的生词 5.记录听写时间、总结时间、总时间
泛听笔记格式要求： 1.听整篇文章，总结文章中心大意 2.对照原文，总结泛听过程中的重点生词 3.记录泛听次数、总时间
这里也给大家三点学习小建议哦~ 精读：如遇到读不懂的复杂句，建议找出句子主干，分析句子成分，也可以尝试翻译句子来帮助理解~ 精听：建议每句不要反复纠结听，如果听 5 遍都没听出来，那就跳过，等完成后再回听总结原因，时间宝贵，不要过于执着哦~ 泛听：每次听全文，边听边记录，不要逐句听或中间暂停，如果听 5 遍都没听懂，那就对照原文总结大意和原因，时间宝贵，不要过于执着哦~
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发表于 2020-8-1 22:08:03
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