What is a species?

New species of lifeforms are being discovered and described on our planet every single day -- but, when we talk about a species, what are we really referring to? Turns out, the answer is... complicated.
This video is by no means comprehensive. Species concepts are some of the most complex and, at times, controversial topics in biology. This video ought to serve as your window down into the rabbit hole. If you're interested in this sort of thing, check out some of the articles below!
Why should we care about species?
www.nature.com/scitable/topicp...
'A list of 26 species 'Concepts''
scienceblogs.com/evolvingthoug...
The 'Open Tree of Life'
tree.opentreeoflife.org/opent...
Amorous turtles:
rsbl.royalsocietypublishing.or...
'Virgin Birth' by shark confirmed; second case ever
www.sciencedaily.com/releases...
big BIG BIG thanks to Drs Caleb McMahan, Olivier Rieppel, and Joyce Havstad for helping this script come together. Your feedback was much appreciated!
Thanks to Matthew Young and everyone else at The Macaulay Library at the Cornell Lab of Ornithology for the meadowlark calls and footage!
Video footage c/o Timothy Barksdale, Jay W. McGowan, and audio by Wilbur Hershberger.
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Come hang out in our Subreddit: / thebrainscoop
Twitters: @ehmee
Facebook: / thebrainscoop
Tumblr: thebrainscoop.tumblr.com
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Producer, Writer, Creator, Host:
Emily Graslie
Producer, Editor, Camera, Graphics:
Brandon Brungard
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This episode is supported by and filmed on location at:
The Field Museum in Chicago, IL
(www.fieldmuseum.org)
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[@besmart]

This is a beast of a topic, and you explained it wonderfully. Very good work!

[@thebrainscoop]

+It's Okay To Be Smart Thanks, Joe!

[@CrankyPantss]

+thebrainscoop I agree. That was a very complicated issue. Well done, as always!

[@nightfqlls_]

your channel is great :)

[@iwillsurvive6156]

Yo.

[@thebrainscoop]

Don't even get me started on the ontological positions of 'species' as they exist in four-dimensionalism

[@Edu_Selva]

+thebrainscoop Amazing video as always.

[@dj_kp437]

+thebrainscoop I saw you at W.I.S.E and I automatically fell in love with you ( not awkwardly ) Thank you for inspiring me!

[@greensteve9307]

+thebrainscoop: Great vid! I love how in Origin of the Species it was pointed out that you can have three sub-species, A-B-C, where B can breed viably with C or A. However, if B goes extinct then A and C are now considered Species not Sub-species, as they can't interbreed

[@theskv21]

Please do start!

[@markholm7050]

Yes, do it!

[@deadeaded]

There's a very good mathematical reason that "species" can't be given a formal definition. Any partition on a set (a.k.a. a classification) is mathematically equivalent to an associated equivalence relation, which is necessarily transitive. If you want parents and children to be the same species, it immediately follows that all organisms are the same species.

[@ragnkja]

+deadeaded Excellent point.

[@lavitorroja2632]

I'm so incredibly late but how doesn't this disprove the whole concept of species ?

[@darkxerneasopenings9135]

Because we need some way of organizing and identifying different organisms from each other.

[@missinglincoln]

I am honoured to be part of the same species as Emily Graslie.

[@frankblangeard8865]

And assuming that the offspring would be fertile.

[@doctorkracko]

and thats just the biological species concept

[@caloocanboy5800]

same

[@caravantea]

I love how good you are at not only explaining what the concept is, but why we should care. Thanks for all your hard work!

[@RDHeath]

The bit that gets me about the evolutionary tree is that it all goes back to one original 'species'. Hence, life came about once. Just once. Then it replicated itself

[@thebrainscoop]

+Robert Heath isn't that just wild

[@moonanddarkness]

+Robert Heath In the strict sense of the phrase, not really... well... it's complicated, you could say it was a collection of proto-life organisms, that had different characteristics and that were already exchanging information among themselves, in other words species and natural or (chemical) selection predates life. Therefore by the time that L.U.C.A. (last universal common ancester) originated, he was one among a whole collection of other organisms which still passed chunks of information among themselves, if you ever look at those phylogenetic trees you will see that the oldest parts of its branches don't just "split" but also combine among themselves. L.U.C.A. is just an extension of this behaviour which as I said started before we considered those organisms to be alive. Can we point out to a single organism which is directly responsible for everything? Sure, but this organism was never alone, in the same sense that the "first" human wasn't.

[@RDHeath]

Nyx & Hemera that was really interesting thank you. I'd never truly considered the chemical evolution before, and I've just done some reading on the topic since you spurred my curiosity. So yeh, thanks! :)

[@chillbro1010]

+Robert Heath Life probably came about millions, billions, or trillions of times but failed. Eventually, one "life" might have made it 100 or even 1000 years before dying out again. Then finally, a "life made it 1,000 years, then 1,000 more, and so on until today.

[@RDHeath]

Connor Hill hadn't thought of that

[@johncarpe]

Again, the truth resists simplicity. Great video!

[@danielleg2687]

Wow! As a biology student currently taking a Speciation course, you have done a fabulous job at summarizing the main topics! Gosh I love your videos, thank you for doing such a wonderful job! Keep them coming!

[@margaretguillory]

The production values of your videos are just outstanding. Thanks so much for putting them out there. I learn something from every one.

[@llpBR]

Every word in this video showed how you love what you study. This is so nice to see!

[@Zeyev]

You discussed animals but plants are so much more randy. They not only breed across "species" boundaries but there are intergeneric hybrids. Arrrggghhh.

[@elfboi523]

+Zeyev It gets especially weird with species in the genus Rubus - blackberries, raspberries, cloudberries, etc. There's an awful lot of species, although many might just be natural hybrids...

[@Silverizael]

+Zeyev Also, what happens with the tree when humans purposefully create new species? Like triticale, which is a hybrid of wheat and rye. Normally, these two species cannot hybridize and produce fertile offspring. They are also in completely different genus. However, by using a mutagenic chemical called colchicine, humans were able to induce polyploidy in one of the two being hybridized and that resulted in an even genome and, thus, fertile hybrid. And triticale was born. Does this count as a new species? It's been used for decades now and is very widespread.

[@elfboi523]

Silverizael Well, it happens in nature, but it's extremely rare. And of course it's a new species.

[@Silverizael]

elfboi523 It just seems like the scientific community is very hesitant to qualify anything we have been involved in making as a separate species. It seems that the idea that we have a significant effect on nature and its development is hard for some to come to grips with.

[@elfboi523]

Silverizael Well, at least most domestic animals aren't separate species, they're just artificial subspecies of wild ones - although several wild ones are extinct now, like the ancestors of our cattle. When it comes to plants, however, most of those are so radically different from their wild ancestors that they're definitely not the same species anymore. Just look at maize.

[@nathanong]

I'm actually in the "species definition" section of On the Origin of Species, and this helps clear things up tremendously. Thanks!

[@Orangensaftmann]

I really loved the way you simplify such a complex matter :) And all your other videos, showing the human and fun behind science!

[@xoxoNateJennyxoxo]

Slightly hilarious that I was only studying the concept of species (even talked about Meadowlarks) a couple of weeks ago in my uni course. Maybe I should suggest this video to my lecturer for next year's lecture on it.

[@thebrainscoop]

+xoxoNateJennyxoxo Please do! (and let me know what they think :D )

[@RickSchwartz]

As always - An excellent educational and fun video!

[@GuilhermeCarvalhoComposer]

Brilliant, brilliant stuff. Yet another video that could hold the channel up all by itself. I really loved it. :)

[@somanshbudhwar]

Video production and content quality is a solid 5/7. Subscribed.

[@prjkaur]

I love how articulate you are. You are a fantastic science educator, in part due to your communication skills. Thanks for the great video on evolutionary concepts.

[@crawfordbrown75]

Emily Graslie I adore what you do, and just promise you will keep on doing it. You have such a unique channel and it's by far one of my absolute favourite science channels. I wish Hank Green would promote you more, you deserve more subscribers.

[@Draxis32]

This channel has become the greatest biology haven in youtube. I wish the Green brothers would summon you Emily to remake SciShow Biology, because with this kind of accurate, well rounded content you produce, I have no doubts you could feed much more brains than the ones you already do here.

[@blackpride354]

are you saying hank and john videos are erroneous?

[@Draxis32]

+Anonymous Unknown Not at all. I am saying that Emily could take a much broader section of Biology(up to college level for sure), unlike the Green brothers who mostly stay at the high school level, something that bothers me quite a lot.

[@FilbieTron]

Hey Emily! Nice video, you did a really good job at going into the nitty gritty of the mess of what species are sometimes. You said the word sustainability and it reminded me of a talk I went to a few weeks ago. The speaker mentioned that the word has lost a lot of meaning because it gets tossed around so much in popular culture now. Maybe you could help elucidate the concept similar to what you did here! ❤

[@IngeborgEngh]

So cool that you also raise the more difficult and philosophical questions in biology :-)

[@noahvcat9855]

This was both entertaining and very interesting for me to watch and now I shall put this information to the test for my Science exam!

[@ClockworkGriffin]

This video is fantastic. I mean I always enjoy this channel, but this video in particular, I very much liked.

[@Supernaturalist1]

THANK YOU! This simplistic definition of species has pissed me off for ages! I knew several examples of fertile cetacean hybrids when this was originally taught to me. Being taught something you know is over simplified is so frustrating! Love that you've gone in depth into this :)

[@ndbiet]

Make episodes about plant species too!

[@1stGruhn]

Being a biology major and a photographer I've always thought of this problem as the difference between a frame and the video from which you got it. You can call the frame a "species" but its still part of a larger whole: the movie. Life is always changing, even current species are changing. The problem is not only in defining past life or even nailing down current life... its a perpetual problem.

[@katherinekragtorp8720]

Beautifully explained - definitely adding it to the supplemental video list I'll be giving my Animal Biology students next semester. Thanks, Emily!

[@Botruc]

Great video! You seem very enthousiastic about the subject and you communicated it very well!

[@redwolfjoy]

Wonderful video! I have a better understanding of why different terms are used when describing a species.

[@torlack]

This was a very good video. Thanks

[@Leophred]

Thank you thebrainscoop. This format works very well. I really enjoyed this video.

[@DanaLeeGibson]

Emily makes me feel good about being stupid. Its comforting to know someone out there is so smart and keeping track of all this stuff.

[@moonanddarkness]

+Dana Lee Gibson You are not stupid, according to Emily she knew pretty much the same information you did when starting to research this video, this doesn't mean she was stupid, this means that she lacked the knowledge on the subject, everyone lacks knowledge over different things, there is no one that just knows it all, intelligence is just our ability to comprehend new information when we face it and incorporate it with our previous knowledge, you aren't stupid for not knowing physics or biology you are ignorant of those topics, but as I said, we are all ignorant in different things, the day we stop bragging about our knowledge and simply pass this information in a humble way while recognizing that we can all learn something from each other we will be able to have conversations without being arrogant or feeling that someone is being arrogant for teaching us something we don't know. I learn stuff from all sorts of people all the time and I grown to appreciate the fact that I can learn something new from almost every single person I encounter.

[@chameleonhound]

Where is the mural that you're standing in front of? It looks really cool, and I'd love to see it in its entirety!

[@sherylhosler9487]

I just received a Tree of Life poster as a gift - I'm going to use it as a background in my videos! :)

[@MatthewSchellGaming]

Funny how the Eastern and Western Meadowlark are so similar yet different species. However you have a vast variety of dogs under one umbrella.

[@rdizzy1]

+Matthew Schell At some point in the future though, if we continue along the same path, these dogs will indeed be different sub-species or species. What is odd about dogs is that, they have such massive differences between breeds, that if they were all extinct millions of years ago, paleontologists (while looking at the fossils)would definitely consider them many different species, instead of breeds of one individual species.

[@joshuamedina7215]

Dogs are all one species because they are all able to breed with each other, if not on their own, then with human intervention. Secondly they all fill the same ecological roles.

[@jaschabull2365]

+Joshua Medina Do they really though? Dachshunds can hunt badgers, while great Danes can't, sheepdogs are used to heard sheep, whereas chihuahuas aren't too useful at that, etc.

[@communistgoatboy]

This was highly enlightening. I now have a much better appreciation for the difficulty in classifying species.

[@CairoFahrenheit]

Awesome video thanks!

[@JoshGister]

+thebrainscoop Clear, concise, and great flow between definitions. Great video, thanks!

[@thomasr.jackson2940]

One thing I wish would be discussed more is why folks obsess so much with putting organisms in such sharply defined categories. Oh sure, it is enormously complicated and you have to organize things somehow to hope to understand it. But as you point out, no one system even works for everything. And the lines aren't sharp, and even if they are now for some or most species, there necessarily was a time in evolutionary history when they weren't. I can understand sharp lined taxonomy as a card catalogue, but it just seems obsessive to want to fit everything in a neat box scientifically. This is especially weird in microbiology where not only is non sexual reproduction the norm, but species regularly exchange genetic information. Like you said, it's all one tree.

[@capofromdabronx6162]

Love listening to her talk 😍😍

[@Xatavor]

Excellent video.

[@Pottery4Life]

One of your better videos, Emily. Thx.

[@r.b.4611]

Great video Em. Spot on.

[@Oldsphere]

If I remember well there're some animals that can form a "ring interbreeding chain". An animal A can interbreed with an animal B, B can interbreed with C but C cannot interbreed with A. According to Biological species concept... what the hell is going on?! Defining things is a hard work... However, you made a great classification of the classification techniques used to classify animals. Big fan of your work!

[@Skip6235]

Also, a big problem with taxonomy (and it's not their fault), is semantics. We are trying to describe things using our limited language. We are also trying to describe groups of individuals in a continuum

[@farmvillepolice]

Great video, Emily. Your hard work paid off.

[@kimmycheyenne]

excellent video!

[@shaunbenton9810]

As always, great video

[@jonasmuller1880]

Interesting and encouraging video:)! It's good to learn some of the theories behind nature once in a while.

[@WireMosasaur]

That mural is amazing. Narwal vs. giant octopus! Adorable baby rhino! Flying bat-eating jellyfish!

[@kirstenmeltesen315]

Emily, how do you prepare for you videos? Do you memorize everything, or read off a script? How much background knowledge do you have going in?

[@thebrainscoop]

+KM Meltesen My background on this topic was pretty weak since going into it this video I thought it was a fairly straight-forward question. So, I had to have lots of conversations with lots of researchers around the building to get a feel for the direction of the video, and I had to define my own goal for it. My goal was that, after watching this, people would have a broader understanding of some of the complications in traditional naming conventions, and an increased appreciation for the complexities of life. If that is what happened, then yay! Goal accomplished. That part of it is important because I couldn't easily go to a researcher and say, "I want this video to be a comprehensive overview of all species concepts." That's not even feasible, nor would it be a well-watched video. It'd... be like an hour-long thing leaving you with more questions than answers. I read a ton of papers on species concepts, went back to our researchers, asked more questions. In meetings, I take lots of notes. Once I had a script I was happy with, I sent it around to get feedback. Then, I incorporate that and tweak stuff. Finally, it's uploaded into an app and I can read the whole thing off of a teleprompter, but by that point I've reworked it so many times I've got chunks memorized anyway. I love The Brain Scoop because it really puts me in a position to learn new things, and forces me to understand them well enough that the information can be disseminated to the public. I was nervous about this video because it's dense, and species concepts are highly controversial in biology. But so far, I haven't received any scathing reviews from colleagues or academics. I am absolutely joyous and proud of what I've done. There is a great sense of accomplishment after doing something like this. :)

[@TheDiabeticChicken]

+thebrainscoop To be honest, I am always left with more question than answers when I watch your channel. But that is why I love watching it. It sparks my curiosity.

[@Schmunzel57]

Next time a video about molecular evolution?

[@jamparker969]

thebrainscoop I've been fascinated with this since I first found out about the platypus in 1st grade. Thanks for educating me!!

[@karleybioanthro]

Awesome video! Could you possibly do an episode all about viruses?

[@evilgenus145]

The background is beautiful in this video. Is it new? or have I just not noticed. Props to the person who painted it.

[@blundershelf]

Great explanation! It certainly helped this biology student :)

[@UnPuntoCircular]

Beautiful video Emily

[@kevintsien]

In your day to day sciencing, do situations where a very precise, albeit a slightly rigid definition of species is required for the science to on arise much?

[@fenfire90]

Wow, I love the comments here! We not only are enthusiastic about biology, but also colours, sounds, math and many more just from this video. So awesome, folks!

[@konraddax3659]

Brainscoop is back! I've been waiting for this! Horray!

[@boyfriend6821]

i really like the "pop pop pop" noise when the texts pops up.

[@oliverhulesch3922]

The description of species as hypothesis at (1:15) was a real eye opener for me, thank you so much for that

[@srinivasar6421]

Very informative

[@jigglemore]

Great video, thank you!

[@silverharloe]

sad all the links cut off early in the description :(

[@thebrainscoop]

+silver Harloe Fixed!

[@bamusbiogenius8738]

Thank you !

[@WB3t0]

Thank you Emily,this is one of your top best videos. It´s like the most controversial question of all time xD Thank you for helping all of the cientific community with your divulgation.

[@jacobdrum]

I love this video. Wish the online Trees of Life were a bit more user-friendly.

[@dasilvaleandro21]

Very nice channel, like from Brazil.

[@MisterTingles]

Wow, this was such a comprehensively researched and presented video! **sigh** Why can't we all be as smart as Emily...

[@olivierk3024]

I subscribed for the dissections, can you make some more of those videos?

[@qorilla]

+Olivier Koot I guess the Field Museum doesn't really like it that much and they think it doesn't fit their image if there's too much gore. The early episodes had this raw and sarcastic and fresh feel to them that has now become just this generic inspirational "science popularization for the whole family, yaay!"

[@SerenityReceiver]

At first I thought this video sounds quite basic but then I learned :)

[@hugofreitasfreitas1047]

great video keep it up

[@calvinball1]

I can't geek out hard enough over how cool this video is for me in my current intellectual journey with Taxonomy!!!!

[@jj-so3og]

Thanks you

[@connorhalleck2895]

This is my favorite episode I've seen on here in a long time, I love it, please make more like this!!

[@mwold98]

Really interesting! x

[@revdj]

Wow. I learned a lot. Thank you!

[@BalletPotter]

Wow! Such a great video, I learned sooooo much thank you!

[@BalletPotter]

Although this could be in part because I was not required to take bio in high school :)

[@erictaylor5462]

Considering that most other animals most likely classify things into only three groups (food, not food and bad, BAD thing) our obsession with making so many classes of things and naming EVERYTHING is pretty weird. Bad, BAD things? those are the things that put you into the "food" category, or at least those scary things that could kill you.

[@alebassmusic]

That's an interesting approach. It would mean a wolf and an active volcano fall into the same category in the eyes of a cute little rabbit, right?

[@MartaniPanganSehat]

Thank you

[@tomcagle2262]

Emily, I am an aide. To my old eyes some of your symetry has changed, you may want to bring this up with your primary physician at next check up. Love your work and sense of humor.

[@nabanaveed4011]

wonderful video I love it

[@Rhobyn]

It seems to me like simple working hypotheses, as most things in language. A simple dogma for the sake of communication. What I wonder, is when the point comes, when our decendants decide that they are different enough from us to reclassify themselves. (And if they will be a bit more creative than to just keep adding sapiens.)

[@MichaelKiddRocks]

very cool video

[@aperturegamerSAC]

Do more insect and bug videos those are always the best

[@Belizle86]

one of my absolute favorite KZbin channels. Keep up the great work Emily and the whole Brainscoop team!

[@morganmae8396]

You looked really cute in this video! Very informative! I love biology, but my diff courses in high school have me burned out and hating my passions. These videos keep me going, thank you!

[@laurenphelps2871]

do you identify as a lumper or a splitter? and in your field/experience/life, how have you seen lumpers v splitters pan out? since h. naledi, i've been really interested and conflicted about speciation within genera. and do you agree with how some groups define species based on ecological and population needs? like, with some monkeys they reclassify populations as different species once they form smaller groups and travel to different areas so they can be put on the endangered animal list and get more attention but they can still breed successfully

[@StevenForditude]

Love this. The evolution exhibit at the Field is my favorite.

[@thebrainscoop]

Mine too!!!

[@ridhimasingh5381]

I understood everything while it was being explained but forgot everything 2 seconds after the video ended

[@pramitbanerjee]

what is the purpose of species level differentiation? if we are having so much trouble, why not create more arbitary terms that defines these new characteristics

[@miaamargareta]

+pramitbanerjee Defining and differentiating between species is important in being able to study organisms so that everyone knows what animal you're talking about. I think the fact that we have so many different definitions of a species shows that we can't find a single one which holds true for EVERY species we know about. As Emily pointed out, there are always exceptions! :)

[@Zalaneax]

Yesss. I needed this. Going to a very religious med school can get exhausting when professors like to blatantly refuse evolution and go on about it in the middle of lecture when it has absolutely nothing to do with the class. I needed some Darwin in my life right about now.

[@markholm7050]

Time to change schools. Professors who knowingly lie to you about the basics are not to be trusted about anything!

[@whereisangie]

great video emily! i love how smoothly you segued between definitions.

[@richa16x]

Polar bears sometimes go to the mainland where they indeed sometimes mate with brown bears and they even eat berries while there are no berries on the north pole.

[@amandasanchez8089]

I'd love to see the blooper reel for this video

[@addaithomas8438]

Thanks

[@Christine34562]

I JUST took an exam with all of this information on it and more for my ecology class. If you had just posted it a yesterday. 😅

[@keithdurant4570]

Absolutely brilliant Emily and the next time I hear someone mention "kind" I will have them watch this...kiddo your wonderful

[@MegaEpicLlama]

+Keith Durant Someone: "Keith, you're so kind" Keith: "WATCH IT, WATCH IT NOW!"

[@arbre4all]

This is awesome!!!

[@johnclavis]

Oh my goodness Emily you are TEH AWESOMESAUCE!