Encore: Babies and toddlers know that swapping saliva is a sure sign of love

Encore: Babies and toddlers know that swapping² saliva³ is a sure sign of love

Transcript⁴

A study suggests babies are aware that people who are willing to share saliva, through kissing or sharing spoons, have especially close relationships. (Story aired on ATC on Jan. 20, 2022.)

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SCIENCE

Even babies and toddlers know that swapping saliva is a sure sign of love

STEVE INSKEEP, HOST:

You maybe know that saying, it ain't worth spit. Well, this story is worth spit because it's about spit. It's about people who share saliva, something you do if you eat off the same spoon or kiss. It's usually a sign that two people are emotionally close. Babies are fountains of drool, so a study examined their views of sharing saliva. Here's NPR's Nell Greenfieldboyce.

NELL GREENFIELDBOYCE, BYLINE⁵: Did you ever see that "Seinfeld" episode where Elaine likes a guy and wants to ask him out on a date?

(SOUNDBITE OF TV SHOW, "SEINFELD")

JULIA LOUIS-DREYFUS: (As Elaine Benes) But then he wiped his hand on the top of the bottle when I offered him water.

(LAUGHTER)

JASON ALEXANDER: (As George Costanza) Well, that doesn't mean anything.

LOUIS-DREYFUS: (As Elaine Benes) Are you kidding? That's very significant. If he was interested in me, he'd want my germs. He'd just crave⁶ my germs.

GREENFIELDBOYCE: It's only funny because it's true.

ASHLEY THOMAS: And the question is sort of, well, how do you know that?

GREENFIELDBOYCE: Ashley Thomas is a researcher at MIT.

THOMAS: Is it something that you know because of years and years of experience with these types of interactions? Or is it something that even infants and toddlers, who have very little experience with these types of interactions, also know?

GREENFIELDBOYCE: To find out, she and some colleagues tested babies and toddlers. The kiddos watched videos of puppet shows. In one, a woman rolls a ball back and forth⁷ with a blue, fuzzy puppet. Then another woman feeds the puppet.

THOMAS: By taking a bite of an orange slice and letting the puppet take a bite of the orange slice and then taking another bite of that same orange slice.

GREENFIELDBOYCE: At the end of the video, the puppet is between these two women and starts to cry.

(SOUNDBITE OF BABY CRYING)

GREENFIELDBOYCE: And it turns out infants and toddlers looked first and looked longer at the woman who'd shared food and saliva. It's like they expected her to do something. That was intriguing⁸, but maybe what mattered was sharing food, not saliva. So the researchers did a study with no food. This time, two different puppets interacted with one woman. The woman shared saliva with only one of the puppets.

THOMAS: The saliva-sharing interaction involved the woman putting her finger in her mouth, putting her finger in the puppet's mouth and then putting her finger back in her mouth.

GREENFIELDBOYCE: With the other puppet, she just touched its forehead and touched her own forehead. Later on, when the woman appeared to be unhappy...

THOMAS: We find that they expect the puppet who had had that mouth-to-mouth interaction to be the one to respond to the woman's distress⁹.

GREENFIELDBOYCE: The researchers report these findings in the journal Science along with the results of another experiment in older children. Five-to-7-year-olds were told about a kid who was sharing stuff - food, toys. And they were asked who the kid was more likely to share with, a friend or a family member. For stuff that could easily be divvied up, there was no difference.

THOMAS: But when it comes to saliva-sharing items, like sharing an ice cream cone¹⁰ or using the same spoon, then kids think that the kid is more likely to share with family.

GREENFIELDBOYCE: Of course, older kids are often explicitly¹¹ told not to swap¹ saliva with others, especially during this pandemic. But how do babies get clued into all this? Alan Fiske is an anthropologist¹² at UCLA. He believes babies are born primed to understand certain basic kinds of human relationships. In one of them, people are socially and functionally¹³ equivalent, and saliva-sharing signals that.

ALAN FISKE: It is a way of connecting bodies or making bodies the same in some respect. And that's the crucial thing.

GREENFIELDBOYCE: He says there's other ways to make bodies feel the same, like close cuddling or sex or even ritually becoming blood brothers, so there's nothing magic about spit.

Nell Greenfieldboyce, NPR News.

(SOUNDBITE OF WILD NOTHING SONG, "PARADISE")

1 swap   

n.交换；vt.交换，用...作交易

参考例句：

• I will swap you my bicycle for your radio.我想拿我的自行车换你的收音机。
• This comic was a swap that I got from Nick.这本漫画书是我从尼克那里换来的。

2 swapping   

交换，交换技术

参考例句：

• The slow swapping and buying of horses went on. 马匹的买卖和交换就是这样慢慢地进行着。
• He was quite keen on swapping books with friends. 他非常热衷于和朋友们交换书籍。

3 saliva   

n.唾液，口水

参考例句：

• He wiped a dribble of saliva from his chin.他擦掉了下巴上的几滴口水。
• Saliva dribbled from the baby's mouth.唾液从婴儿的嘴里流了出来。

4 transcript   

n.抄本，誊本，副本，肄业证书

参考例句：

• A transcript of the tapes was presented as evidence in court.一份录音带的文字本作为证据被呈交法庭。
• They wouldn't let me have a transcript of the interview.他们拒绝给我一份采访的文字整理稿。

5 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

6 crave   

vt.渴望得到，迫切需要，恳求，请求

参考例句：

• Many young children crave attention.许多小孩子渴望得到关心。
• You may be craving for some fresh air.你可能很想呼吸呼吸新鲜空气。

7 forth   

adv.向前；向外，往外

参考例句：

• The wind moved the trees gently back and forth.风吹得树轻轻地来回摇晃。
• He gave forth a series of works in rapid succession.他很快连续发表了一系列的作品。

8 intriguing   

adj.有趣的；迷人的v.搞阴谋诡计(intrigue的现在分词)；激起…的好奇心

参考例句：

• These discoveries raise intriguing questions. 这些发现带来了非常有趣的问题。
• It all sounds very intriguing. 这些听起来都很有趣。 来自《简明英汉词典》

9 distress   

n.苦恼，痛苦，不舒适；不幸；vt.使悲痛

参考例句：

• Nothing could alleviate his distress.什么都不能减轻他的痛苦。
• Please don't distress yourself.请你不要忧愁了。

10 cone   

n.圆锥体，圆锥形东西，球果

参考例句：

• Saw-dust piled up in a great cone.锯屑堆积如山。
• The police have sectioned off part of the road with traffic cone.警察用锥形路标把部分路面分隔开来。

11 explicitly   

ad.明确地，显然地

参考例句：

• The plan does not explicitly endorse the private ownership of land. 该计划没有明确地支持土地私有制。
• SARA amended section 113 to provide explicitly for a right to contribution. 《最高基金修正与再授权法案》修正了第123条，清楚地规定了分配权。 来自英汉非文学 - 环境法 - 环境法

12 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。

13 functionally   

adv.机能上地，官能地

参考例句：

• Objective To explore occlusion reconstruction by computer aided design (CAD) with functionally-generated pathway (FGP). 目的探索借助功能性？记录(functionally-generated pathway,FGP)技术进行口腔固定修复体计算机辅助设计(Computer aided Design,CAD)生理性建？的方法。 来自互联网
• In this respect, the proceeding was functionally similar to a comparative licensing adjudication. 在这一点上，手续在作用上即类似于比较许可证发放的裁断。 来自英汉非文学 - 行政法