Thanks to Brilliant for supporting this episode of SciShow.
感谢Brilliant网站对本集《科学秀》的支持
Go to Brilliant.org/SciShow to learn how you can take your math skills to the next level!
快去Brilliant.org/SciShow学习怎样提升你的数学能力吧！
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狗狗们生长得有多快？
It’s pretty obvious that dogs age faster than we do.
显而易见 狗狗比人类生长得快多了
Like, you might have heard that your dog’s age
比如 你也许听说过
is their human years multiplied by seven.
狗狗的实际年龄相当于人类年龄的七倍
But that is just, like, a made up myth…thing.
不过 这个说法其实是捏造的
And we have looked at it scientifically,
而如果用更科学的方式来看待这个问题
and what we have discovered is weirder and more interesting than you might think:
我们得到的发现比你以为的更古怪有趣
Your dog is aging both more quickly—and more slowly.
狗狗生长的速度 其实既快又慢
How old your dog is in human years might seem like a meaningless question.
研究狗狗所对应的人类年龄看似没什么意义
But veterinarians can use that kind of comparison
但通过这种比较
to determine what kind of care their patients’ need.
兽医能够知道他们的病患需要何种照料
Because, in many ways, dog bodies age much like human ones do.
因为狗狗身体的生长在各个方面都和人类很相似
Like, they develop gray hair,
比如 它们也会长白发
and their limbs and joints stop working well.
四肢和关节也会变得不听使唤
(Not that I would know anything about that!)
不过我现在可从没切身体会过这些情况噢
But the speed at which dogs get old is very different from us:
但狗狗生长的速度和人类具有很大差异
they actually age much faster during the first part of their lives!
实际上 它们只在狗生的第一阶段里生长迅速
To get an estimate for how fast,
为了估算出其具体速度
back in 1953, a French researcher lined up
1953年时 法国一位研究者
major life events in humans and dogs—
列出了人类和狗狗生命中的主要事件
so, things like puberty and death.
比如青春期和死亡时间这种
From that, he proposed that
他从中得出结论
puppies age 15 to 20 times faster than people!
幼犬的生长速度是人类的15到20倍
Like, a one year-old dog is roughly equivalent to a 15 year-old person.
也就是说 狗狗的一岁大致相当于人类的十五岁
Once they fully mature, however, their aging slows down.
不过 狗狗们一旦成年 生长速度就会慢下来
And eventually, he thought aging levels out to about a one in five—
他最终认为 成年期的生长速度比是1比5
for every year that passes, dogs age as much as we do in five years.
即狗狗每年的生长速度相当于人类的五年
But in a paper published in 2020,
但加州大学圣地亚哥分校医学院的研究者们
researchers from the UCSD School of Medicine
在2020年发表了一篇论文
showed that dogs age even faster than that
他们认为狗狗的生长速度其实比那还快
— and then, slower.
接着就慢下来了
This insight came from looking at measurable marks on DNA
通过观察DNA上随时间变化的可观测标记
that change over time.
他们得出了这一结论
These marks are called methylation marks
这些标记被称为甲基化标记
because they’re made by the addition of a methyl group:
因为添加了甲基
a carbon atom surrounded by hydrogens.
即一个碳原子外环绕着氢原子
Adding a methyl group to DNA
在DNA上加入一个甲基
can affect whether the genes in that area are active,
可以影响该区域内基因的活跃情况
so patterns of methylation marks across the genome
因此 整个基因组上甲基化标记的模式
change with things like age and disease.
会随年龄增长和疾病等因素而变化
So, the researchers decided to use these patterns to more precisely determine
研究者遂决定利用这些模式来更精确地研究
how dog years translate to human ones.
狗狗年龄与人类年龄的相互转化
Specifically, they examined the methylation patterns of 104 Labrador retrievers
确切地说 他们研究了104只拉布拉多搜寻犬的甲基化模式
—from few-week-old puppies to 16-year-old dogs.
年龄从几周大到16岁不等
And they compared them to the patterns from humans of varying age,
将拉布拉多犬的甲基化模式与同年龄人类进行比对
paying especially close attention to developmental milestones in both species.
密切关注两个物种间的发育节点
Turns out a one-year-old lab’s body has actually aged
结果发现实验中1岁的拉布拉多犬已经
about as much as a 30 year-old human’s!
相当于人类的30岁
After about seven years, though,
不过大约7年之后
this slows to roughly 1.6 human years of aging per dog year.
狗狗的发育减慢 1年约等于人类的1.6年
So, they age much slower than we thought once they become senior puppers.
所以狗狗成年后的生长速度比我们想象的要慢得多
Those exact numbers might not work for every dog, of course.
当然这些确切的数字可能并不适用于每只狗狗
Previous research suggested that breed and size can impact aging.
先前研究表明 狗狗的品种和体型大小都会影响生长速度
So, the researchers will need to examine more dogs,
所以科研人员们需要研究更多的狗狗
and potentially come up with breed-specific age comparisons.
然后才可能得出各品种间生长速度的比较
Still, these results give us a much better sense of the rate at which dogs are aging.
但这些结果使我们对狗狗的生长速度有了更直观的了解
And that knowledge may help veterinarians better diagnose and treat
在未来 这些知识可以帮助兽医更好地诊断和治疗
age-related conditions in them in the future.
狗狗们年龄相关的问题
It may mean they should be testing for some things
比如 这可能意味着在狗狗生命的早期
or providing certain therapies earlier in life, for instance.
就应该进行一些检测或提供某些治疗
So even if it seems goofy to think of your four year-old doggo as middle-aged,
虽然把你4岁的狗狗当作一个中年人这似乎很愚蠢
measuring your pup in human years isn’t a silly exercise.
但是以人类的年龄去衡量你的狗狗并不愚蠢
It could help your furry friend live a longer, healthier life.
这可以帮助你的好朋友活得更长寿更健康
You know, all this talk about aging rates and how they change over time
我们谈到的生长速度和它们随着时间的变化
has got me thinking I could use a bit of a math refresher.
让我觉得有必要复习数学了
And luckily, that’s something today’s sponsor, Brilliant, can help with.
幸运的是 我们的赞助商Brilliant可以提供这些帮助
They have more than 60 fun, interactive courses that cover topics in science,
他们有60多种有趣的互动式课程 涵盖科学
computer science, and of course, math.
计算机科学 当然也有数学
Their new Math History course is really fun.
他们最新的数学历史课非常有趣
You basically travel back in time
你会回到过去
to learn mathematical concepts alongside the mathematicians that figured them out!
与发现那些数学概念的数学家们一起学习数学
And speaking of doing the math, right now, the first 200 people to sign up at Brilliant.org/SciShow
说到学习数学 现在前200名注册Brilliant.org/SciShow的用户
will get 20% off an annual Premium subscription!
可以得到20%的包年订阅折扣
So if you like math and saving money,
如果你喜欢数学并想省钱的话
you’ll probably want to head over there soon.
你可得赶紧去注册啦
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