Infants and Apes Remember Things Similarly
Infants and apes apparently1 adopt the same tactics（1） for remembering where things are, but as children develop their strategies change, a new study shows.
The findings might reveal in part how the minds of our distant ancestors shifted gears（2） to embark2（3） on the road toward humanity.
There are two basic strategies animals use to remember where things are. Either they remember a thing's features, such as whether it was a banana, or they remember its place in space, such as left.
All animals scientists have tested seem to employ both strategies. However, if experiments are rigged（4） such that animals had to choose between the tactics, some species, such as chickens and toads（5）, prefer a feature-based strategy. Others, such as fish and dogs, favor a place-based strategy.
Researcher Daniel Haun at the Max Planck Institute for Evolutionary4 Anthropology5 in Leipzig, Germany and his colleagues investigated orangutans（6）, gorillas（7）, bonobos（8）, chimpanzees（9） and humans. They wanted to see whether humanity and its closest relatives all adopted the same strategies for remembering where things are. Any changes in strategy between species or within species would shed light on how they all evolved.
At the Leipzig Zoo, the scientists hid rewards such as grapes, banana slices or toy animals under either a hollow piece of wood, an imitation（10） bird's nest or an artificial hollow rock.
At times, the rewards were concealed8（11） under the same object they were hidden beneath previously9, whose place had changed. A feature-based strategy would best find these coveted10 items.
At other times, the rewards were hidden at the same place they were concealed before, but under a different object. A place-based strategy would best discover these items.
When human infants are a year old, they favor place-based strategies like all the other great ape species do. This suggests human and ape brains start out the same, at least when it comes to remembering where things are. The most recent common ancestors between humans and all the other great apes date back to about 15 million years ago, suggesting this common preference has been part of our brain structures since at least then.
However, three-year-old children preferred a feature-based strategy. The researchers noted11 this shift in strategy coincided with a period when humans are first drawn12 into social life and acquire skills such as spoken language.
1. tactics：战术、方案
2. gear：齿轮
3. embark：登上
4. rig：操纵
5. toad3：癞蛤蟆
6. orangutans：猩猩，一种大型的树栖类人猿，产于波罗门和苏门答腊，有稀疏的红棕毛皮、非常长的臂且无尾
7. gorilla6：大猩猩，栖居在赤道非洲的最大的类人猿，体型粗壮，头发非常粗，呈深棕色或黑色
8. bonobo：产于非洲刚果河以南的倭黑猩猩
9. chimpanzee：黑猩猩产于非洲热带区域的一种长有长长的黑毛群居类人猿，有一些栖于树上的生活习惯且表现出与人类一样的行为与高等的智商
10. imitation：仿造物
11. conceal7：隐藏
一项新的研究显示，孩子和猿用同样的办法来记忆物品所在的地方，但当孩子们越长越大，他们的办法就会改变。
这类发现或许能在一定量上说明大家的远祖是怎么样转舵走上人性的道路。
动物记忆物品地方的办法有两种。一种是通过记忆物品的特征，比如它是不是是一个香蕉；另一种则是通过记忆物品所在的空间地方，比如是不是在左侧。
受测的科学家们会同时采取两种办法。但在同样的实验中，动物们则会选择其中一种，一些物种，比如鸡和蟾蜍会选择特征记忆法。其他的，比如鱼和狗更喜欢空间记忆法。
德国莱比锡普朗克演化人类学研究所研究职员丹尼尔焕和同事们分别对猩猩、大猩猩、倭黑猩猩、黑猩猩和人类进行了研究。他们期望知道人类会不会和他们近期的亲戚选择同样的记忆办法。不同物种之间和同一物种间的办法改变都能说明演化的过程。
在莱比锡动物园，科学家们把如葡萄、香蕉片、动物玩具等奖品放入空木头、假鸟窝或者人造空石头里面。
当研究职员用同样的掩饰物藏匿奖品，只不过改变了它们的地方的时候，善用特征记忆法的动物比较容易找到这类诱惑的奖品。
当研究职员没移动物品，只不过改变了藏匿物品的掩盖物的时候，善用空间记忆法的动物则能非常快发现物品。
一岁左右的孩子和猿类一样选择空间记忆法。这说明至少在物品地方记忆方面，人类和猿类大脑刚开始是一样的。可证明的人类和猿类拥有一同祖先的近期时间是1500万年前，也就是说至少从那个时候起，人类和猿类就拥有同样的记忆办法。
但，三岁的孩子就会选择特征记忆法。研究职员说这种转变正与人类刚刚踏入社会生活相对应，那个时候大家掌握了不少技能，比如说话。
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