評(píng)論
打印
Listen to part of a lecture in a biology class.
請(qǐng)聽(tīng)生物課上一個(gè)講座的片段。
Ok. There are two major types of classifiers in the world, people we call lumpers and people we call splitters.
好的。世界上有兩種主要類型的分類者--我們稱之為“統(tǒng)合派”和“分割派”。
A lumper is someone who tries to put as many things as possible in one category.
統(tǒng)合派是指那些試圖將盡可能多的事物歸入同一類別的人。
Splitters like to work for the differences and put things in as many different categories as possible.
而分割派則熱衷于尋找差異，并將事物劃分到盡可能多不同的類別中。
Both lumpers and splitters work in the business of defining biological classifications.
統(tǒng)合派和分割派都在從事生物分類定義的工作。
The great philosopher Aristotle is generally considered the first person to systematically categorize things.
偉大的哲學(xué)家亞里士多德通常被認(rèn)為是系統(tǒng)分類事物的第一人。
He divided all living things into two groups. They were either animal or vegetable. And these categories are what biologists came to call "kingdoms".
他將所有生物分為兩大類：要么是動(dòng)物，要么是植物。生物學(xué)家后來(lái)將這些類別稱為“界”。
So if it ran around, it was an animal, a member of the animal kingdom. And if it stood still, and grew in the soil, it was a plant, a member of the plant kingdom.
因此，能四處活動(dòng)的生物就是動(dòng)物，屬于動(dòng)物界；而靜止不動(dòng)并在土壤中生長(zhǎng)的，則是植物，屬于植物界。
This system, organizing all life into these two kingdoms, worked very well for quite a while, even into the age of the microscope.
這種將所有生命劃分為兩界的系統(tǒng)沿用許久，甚至延續(xù)到顯微鏡時(shí)代。
With the invention of the microscope, in the late 1500s, we discovered the first microorganisms.
隨著16世紀(jì)末顯微鏡的發(fā)明，我們發(fā)現(xiàn)了第一批微生物。
We saw that some wiggled and moved around and others were green and just sat there.
我們觀察到有些微生物會(huì)扭動(dòng)移動(dòng)，而另一些呈綠色且靜止不動(dòng)。
So the ones that moved like animals were classified as animals, and the more plant-like ones as plants. Oh, before I go on I must mention Carolus Linnaeus.
于是像動(dòng)物般移動(dòng)的被歸為動(dòng)物，植物形態(tài)的則歸為植物。哦，在繼續(xù)之前，我必須提到卡爾·林奈。
A hundred years or so after the invention of the microscope, Carolus Linnaeus devised a simple and practical system for classifying living things, according to the ranks of categorization still in use today -- class, order, family and so on.
顯微鏡發(fā)明約百年后，卡爾·林奈設(shè)計(jì)了一個(gè)沿用至今的、簡(jiǎn)單實(shí)用的生物分類系統(tǒng)，包含綱、目、科等層級(jí)分類。
And by further best aspect of the Linnaeus system, is the general use of binomial nomenclature, having just two names to describe any living organism.
林奈系統(tǒng)最杰出的貢獻(xiàn)是普遍采用二名法命名法，也就是用兩個(gè)名稱描述任何生物。
This replaced the use of long descriptive names, as well as common names which vary from place to place and language to language.
這取代了冗長(zhǎng)的描述性名稱和因地而異、因語(yǔ)言而異的俗名。
Binomial nomenclature gives every species a unique and stable two-word name, agreed upon by biologists worldwide.
二名法命名法為每個(gè)物種賦予了全球生物學(xué)家公認(rèn)的唯一且穩(wěn)定的雙詞學(xué)名。
But not everything about this system remained unchanged. Take for example the mushroom, a fungus.
但該系統(tǒng)的某些部分并非一成不變。以蘑菇這類真菌為例。
It grew up from the ground and looked like a plant. So it was classified as a plant.
它們從地面長(zhǎng)出，形似植物，因此最初被歸入植物界。
But using the microscope we discovered that a fungus contains these microscopic thread-like cells that run all over the place. And so it's actually not that plant-like.
然而通過(guò)顯微鏡，我們發(fā)現(xiàn)真菌內(nèi)部遍布絲狀細(xì)胞結(jié)構(gòu)。這實(shí)際上與植物差異顯著。
So in this case, the splitters eventually won, and got a third kingdom just for the fungus.
因此在這個(gè)案例中，分割派最終獲勝，為真菌單獨(dú)設(shè)立了第三界。
And as microscopes improved, we discovered some microorganisms that were incredibly small.
隨著顯微鏡技術(shù)的進(jìn)步，我們發(fā)現(xiàn)了極其微小的微生物。
I'm talking about bacteria. And we could see that they didn't have what we call a nucleus.
我們要談的就是細(xì)菌。我們能看到，它們沒(méi)有細(xì)胞核。
So they got their own kingdom, a kingdom of very tiny things without nucleoli.
因此它們有了一個(gè)屬于自己的界，一個(gè)由無(wú)核的微小生物組成的界。
So then we had several kingdoms for plants and for animals, and the different kinds of fungus like mushrooms, and for these tiny bacteria.
至此我們有了植物界和動(dòng)物界，還有不同種類（比如蘑菇）的真菌的界，還有這些微小的細(xì)菌的界。
But we also had some other microorganisms that didn't fit anywhere. So biologist gave them their own kingdom.
但我們還有一些無(wú)法歸類的微生物，因此生物學(xué)家遂為其設(shè)立了一個(gè)界。
And this fifth kingdom was sort of anything that doesn't fit in the first four kingdom, which upset some people. And then there was a question of viruses.
這第五界成了前四界無(wú)法歸類之物的集合，引發(fā)了爭(zhēng)議。此外還有關(guān)于病毒的問(wèn)題。
Viruses have some characteristics of life but don't reproduce on their own or use energy. So we still don't know what to do with them.
病毒具有某些生命特征，但無(wú)法自主繁殖或消耗能量，因此我們至今未對(duì)其分類。
The lumpers want to keep viruses in the current system. Some of the splitters say to give them a separate kingdom.
統(tǒng)合派希望將病毒保留在當(dāng)前系統(tǒng)中。而一些分割派則主張另立新界。
And the extreme splitters say that viruses have nothing at all to do with living things and keep them out of my department.
極端分割派認(rèn)為病毒與生物毫無(wú)關(guān)聯(lián)，應(yīng)完全排除在分類體系外。
Recent research though has moved to see yet another direction. Nowadays when we want to determine the characteristics of something, we look at its biochemistry and its genetic material.
然而，最近的研究已經(jīng)開(kāi)辟了另一個(gè)方向。如今，當(dāng)我們想確定某物的特征時(shí)，我們會(huì)看它的生物化學(xué)和遺傳物質(zhì)。
And what we've discovered is that some bacteria are not like the others. Many of these are called extremophiles.
研究發(fā)現(xiàn)，某些細(xì)菌與眾不同，許多被稱為“嗜極生物”。
They live in very strange places, in polar ice or in a boiling water of hot springs or in water so salty other organisms couldn't live there.
它們棲居在非常奇怪的地方--極地冰層、溫泉沸水或高鹽度水域，其他生物無(wú)法在那里生存。
Extremophiles tend to have a different chemistry from other bacteria, a chemistry that in some case is actually more related to plants and animals than to previously known bacteria.
這些嗜極生物往往具有與其他細(xì)菌不同的化學(xué)成分，在某些情況下，這種化學(xué)成分實(shí)際上與植物和動(dòng)物的關(guān)系比之前已知的細(xì)菌更密切。
So what to do with this strange bacteria? Well, one thing we've done is creating a new set of categories, the domains, overarching the different kingdoms.
所以如何歸類這些奇特的細(xì)菌？我們目前創(chuàng)建了新的分類層級(jí)--域，覆蓋各生物界。
Biologists now recognize three domains. But even as we talk about these new domains, well, come back in a few years and it might all be different.
目前生物學(xué)家承認(rèn)三個(gè)域。但正如我們討論這些新域時(shí)所言，或許幾年后再看，一切又將不同。
