that's gone bad or a batch of cookies fresh from the oven.

或者是一批剛出爐的餅乾。

The human nose can identify some 1 trillion smells, but it's just not that impressive

人類的鼻子可以識別大約1萬億種氣味，但它並不那麼令人印象深刻。

compared to many members of the animal kingdom.

與動物界的許多成員相比。

Take the elephant, for example, that trunk isn't just for grabbing peanuts, it's sniffer

就拿大象來說，那鼻子不光是用來抓花生的，它是嗅覺靈敏的人

is so powerful it can smell water from miles away. The trunks are also wildly multifunctional;

是如此強大，它可以在幾英里外聞到水的味道。樹幹也是野生的多功能。

as a straw,

作為一根稻草。

a dexterous limb, a vibration sensor, and of course, a trumpet.

一個靈巧的肢體，一個振動傳感器，當然還有一個小號。

Alright, you guys ready?

好了，你們準備好了嗎？

Which kind of begs the question, what is a nose? This isn't technically a nose.

這就引出了一個問題，什麼是鼻子？嚴格來說，這不是一個鼻子。

It's more of a bony horn.

它更像是一個骨角。

This is a nose, but it's also a voice amplifier and somehow, a feature for attracting mates.

這雖然是個鼻子，但它也是一個語音放大器，而且不知為何，它還有吸引伴侶的功能。

So by definition a nose just has to be a part of a face or facial region that contains nostrils

所以，根據定義，鼻子只要是面部或面部區域中包含鼻孔的部分就可以了。

and the organs of smell.

和嗅覺器官。

After that noses vary wildly in both aesthetics and function.

之後鼻子在美學和功能上都有很大的不同。

Now I want to talk about a nose that is not only highly sensitive, but also has the impressive

現在我想說的是一個鼻子，不僅靈敏度高，而且還擁有令人印象深刻的

ability to remember smells over long periods of time.

長時間記憶氣味的能力。

They also might be the cutest... I'm talking about dogs.

他們也可能是最可愛的... ...我說的是狗。

This is my dog Henry.

這是我的狗亨利

I think he's a chihuahua toy fox terrier mix, but he loves treats.

我想它是一隻吉娃娃玩具狐狸梗混種犬，但它喜歡吃東西。

There you go.

這就對了

But when I hold this treat up for him, Henry's not just smelling like

但當我拿著這個點心給他吃的時候，亨利不只是聞起來像...

"yep, that's a treat."

"是的，那是一種享受。"

He's smelling in layers, so Henry's smelling the wheat flour, the chicken, the yeast that

他的氣味是層層疊疊的，所以亨利聞到的是小麥粉，雞肉，酵母的氣味。

make up this treat, all separately.

組成這種待遇，都是分別。

This is why dogs can detect illegally smuggled items buried in luggage and can even find

這就是為什麼狗能檢測到埋在行李中的非法走私物品，甚至能發現。

people buried in avalanches.

埋在雪崩中的人。

So how does this work.

那麼，這是怎麼做到的呢。

Well, it all comes down to the structure of the nose and the sensory abilities of the

好吧，這一切都要歸結於鼻子的結構和感官能力。

brain, when Henry inhales his nostrils pull in air packed with molecules that contain smells.

大腦，當亨利吸氣的時候，他的鼻孔里拉進了含有氣味的分子的空氣。

A fold of tissue just inside his nostrils separates the airflow into two paths, one

鼻孔內的組織褶皺將氣流抽成兩條路，一條是... ...

for olfaction or smells, and the other one for respiration.

用於嗅覺或氣味，另一個用於呼吸。

This prevents the dog from immediately breathing out to smell like we do.

這樣就可以避免狗狗像我們一樣馬上呼吸出氣味來。

When they do exhale air exits through different slits in the sides of their nose.

當他們呼氣時，空氣從鼻翼兩側的不同縫隙中排出。

This helps pull new odors into the nose through the nostrils and allows the dog to sniff practically

這有助於將新的氣味通過鼻孔拉進鼻子，讓狗狗聞到幾乎所有的氣味。

continuously.

連續。

It also helps the dogs can identify which nostrils smell came through, so that they

它還可以幫助狗狗辨別哪一個鼻孔的氣味傳來，使它們的嗅覺更加靈敏。

can locate which direction the smell is coming from.

可以定位氣味來自哪個方向。

Pretty helpful for early dogs that needed

對早期的狗來說，相當有幫助，需要

to hunt prey in the wild, or in Henry's case, finding the treats I've been hiding around the

在野外追捕獵物，或者在亨利的情況下，找到我一直藏在周圍的食物。

house.

房子。

After inhalation and separation from the air going to the lungs, a small amount of air

吸入並與進入肺部的空氣分離後，少量的空氣。

passes over turbinates.

通過湍流。

Turbinates are these plates of bony structures that contain scent-detecting cells.

Turbinates是這些骨質結構的板塊，其中包含有氣味檢測細胞。

There's even a separate section called the vomeronasal organ, which is used primarily

甚至還有一個獨立的部分，叫做嘔吐器官，主要用於

for social interactions.

為社會交往。

So, mostly for sniffing butts.

所以，主要是用來聞屁屁的。

Dog noses are thought to contain roughly 40 times the number

狗的鼻子被認為含有大約40倍於狗的數量。

of smell receptors that humans have.

的嗅覺感受器，人類有。

More if you're looking at a highly sensitive dog like a bloodhound.

如果你要找的是像獵血犬這樣的高敏感度的狗，那就更多了。

All dogs have talented sniffers, but it's a spectrum, some breeds are definitely

所有的狗都有嗅覺天賦，但這是一個範圍，有些品種絕對是

better than others.

比別人好。

Bloodhounds actually have more scent receptors than most dogs.

獵血犬的氣味受體其實比大多數狗都多。

They also have other features that make them the famous nose-with-a-dog-attached.

它們還有其他特點，使它們成為著名的帶狗的鼻子。

In fact, those skin rolls that make bloodhounds so unique, actually help them trap and collect

事實上，那些使獵犬變得如此獨特的皮卷，其實是幫助它們捕捉和收集的。

scent particles.

氣味顆粒。

From here, the detected smells are converted into nerve impulses and sent

從這裡，檢測到的氣味被轉換成神經衝動，併發送

to the olfactory bulb in the brain.

到大腦中的嗅球。

Within the olfactory bulb, an odor image is created,

在嗅球內，就會產生氣味影像。

combining all the individual smells into a cohesive identifiable one.

將所有單獨的氣味結合成一個有凝聚力的可識別的氣味。

This is what helps dogs retain memories of scents for very long periods of time.

這就是幫助狗狗在很長時間內保留氣味記憶的原因。

There's another characteristic of a dog's nose that makes it unique; the wet and coldness of it.

狗狗的鼻子還有一個特點，那就是它的溼潤和冰涼。

This is called a rhinarium, and it's that furless skin at the end of a nose.

這叫鼻樑，就是鼻子末端那層沒有毛的皮膚。

Now scientists aren't exactly sure what function is serves.

現在科學家們還不完全確定是什麼功能。

Recent research suggests that it serves as a thermal radiation detector helping dogs

最近的研究表明，它可以作為熱輻射探測器，幫助狗。

sense heat.

感知熱量。

It could also just help scent molecules stick to the nose.

它也可能只是幫助氣味分子粘在鼻子上。

I just want to eat you up.

我只想把你吃了。

What do you think of that?

你怎麼看？

As a vet I often get asked if a dry nose is a sign of illness.

作為一名獸醫，我經常會被問到，鼻子乾燥是不是疾病的信號。

I tell them it can vary from species to species and just because your dog's nose is dry at

我告訴他們，不同的物種會有不同的情況，只是因為你的狗的鼻子乾燥，在

that time it doesn't necessarily mean that something we need to be concerned about.

那個時候不一定意味著我們需要關注的東西。

These highly sensitive noses combined with their ability to be highly trained makes dogs exceptional

這些高度敏感的鼻子，加上它們接受高度訓練的能力，使狗狗們變得非常出色。

companions for jobs that require an acute sense of smell.

對於需要敏銳嗅覺的工作來說，是個好夥伴。

I spent time with some of the best working with the Wildlife College and the Ivan Carter

我花時間與一些最好的工作與野生動物學院和伊萬-卡特。

Wildlife Conservation Alliance in South Africa.

南非野生動物保護聯盟；

They use bloodhounds trained at a very young

他們使用的獵犬是在很小的時候就開始訓練的

age to track poachers in national parks and there's even a dog that tracks orphan baby

追蹤國家公園裡的偷獵者，甚至還有一隻狗，可以追蹤孤兒寶寶的蹤跡

rhinos, so these guys can be rescued and protected.

犀牛，所以這些傢伙可以被拯救和保護。

Without these dogs we would catch poachers 4 to 6% of the time, implementing these

如果沒有這些狗，我們會在4到6%的時間裡抓到偷獵者，實施這些。

dogs where they're finding poachers 75 to 80% of the time, and they often catch them before

在那裡，他們發現偷獵者的狗75％至80％的時間， 他們往往抓住他們之前， -

rhinos been killed.

犀牛被殺。

Thanks to their incredible noses, we've been able to protect hundreds of animals from poachers

多虧了它們不可思議的鼻子，我們才得以保護數百隻動物不被偷獵者獵殺。

and rescue several baby orphan rhinos too.

並救出幾隻小犀牛孤兒。

Thanks for watching our new series Tusks to Tails.

感謝您收看我們的新系列《從牙到尾》。

I'm Dr. Evan Antin, with my dog Henry, and if there's an animal you would like us to

我是Evan Antin醫生，和我的狗Henry在一起，如果你想讓我們幫你找一隻動物的話

feature, please leave it in the comments.

功能，請在評論中留下。

We'll see you next time.

我們下次再見。