There’s No Such Thing As “Warm-” Or “Cold-” Blooded

The concept of warm-blooded and cold-blooded animals is outdated because there are actually tons of different animal thermoregulation strategies.
LEARN MORE
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To learn more about this topic, start your googling with these keywords:
- Thermoregulation: the strategy through which the body maintains its internal temperature.
- Endotherm: an animal that generates most of its heat internally.
- Ectotherm: an animal that relies on environmental heat sources.
- Mesotherm: an animal with an intermediate heat generating strategy.
- Poikilotherm: an animal whose internal temperature varies considerably.
- Heterotherm: an animal that sometimes keeps its body temperature the same and sometimes lets it vary.
- Homeotherm: an animal whose internal temperature does not change much.
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REFERENCES
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Tøien, Ø., Blake, J. & Barnes, B.M. Thermoregulation and energetics in hibernating black bears: metabolic rate and the mystery of multi-day body temperature cycles. J Comp Physiol B 185, 447-461 (2015). doi.org/10.1007/s00360-015-08...
Paladino, F.V., O’Connor, M.P., Spotila, J.R. 1990. Metabolism of Leatherback Turtles, Gigantothermy, and Thermoregulation of Dinosaurs. Nature. Vol.344;858-860. REtrieved from: www.nature.com/articles/344858a0
Morrissette, J.M. (2003). Characterization of ryanodine receptor and Ca2+-ATPase isoforms in the thermogenic heater organ of blue marlin (Makaira nigricans). Journal of Experimental Biology, 206(5), 805-812. Retrieved from: pubmed.ncbi.nlm.nih.gov/12547...
Polymeropoulos, Elias. (2022) Personal Communication. University of Tasmania. www.utas.edu.au/profiles/staf...

[@MinuteEarth]

Check out our store at dftba.com/minuteearth We just released new PINS and STICKERS and a MAGNET, all featuring science stories that inspire love and curiosity about our wonderful planet!

[@alto7183]

Buen video, me imagino también los bordes de los animales biológicos mamíferos de hervivoro, omnivoros y carnívoros sean entonces una escala de grises mínimo en habitables biológicas para sobrevivir como este ejemplo, no me extrañaría ver entonces a futuro similitudes entre especies inteligentes biológicas mamíferos afines como startreck con los vulcano y los caitian en ejemplo burdo, ya ni hablar entre mentalistas naturales de cada especie inteligente biológica, como la segunda fundacion de Isaac assimov y dune de frank herbert las bene jeserit sugerencia.

[@highalpine7321]

Pacific Coast Trail.. Fact Check or Proof Read Much?? Your a phony

[@purplenebula8451]

Do an update on the spotted hyena hierarchy. I have emailed you the newer one. Female spotted hyenas don't dominate males because of aggression but because of social support and most males are immigrants. Males can also become in a high-ranking position if they're related to a high-ranking mother. A male can lead his clan. Immigrant males can also lead the clan if the high-ranking males die. Females can also be low ranking if they leave their clan

[@mdakhladhussain581]

Hello sir What is the natural year-round climate?

[@InfernalPasquale]

As a science teacher, it's because there is SO MUCH to learn. In this example, you are teaching young children about the basics of taxonomy, so when they advance to the next level, which is a bit more nuanced and complicated, they will have a greater chance of understanding it. This continues at each step in the learning process. Even undergraduate science is still sometimes completely wrong and often only partially correct.

[@juliaf_]

"Assume a spherical cow in a vacuum" Sometimes to learn something, it has to be simplified to the point where it's useless for anything but learning, so that later you can correct it little by little until it starts to become useful again :)

[@TaliesinMyrddin]

Part of why "it's first-grade science" is so infuriating to hear. It doesn't mean it's the most fundamental, core, objectively solid piece of science relating to the subject, it means it's the most parsed-down, simplistic interpretation developed solely to teach children what they need to get to university where they are told to forget what they know apart from how to learn

[@xXJ4FARGAMERXx]

@@TaliesinMyrddin in first grade we learned that 3 - 5 doesn't exist, now we know it's -2. Which is more correct? First grade or now?

[@TaliesinMyrddin]

@@xXJ4FARGAMERXx I'm not entirely sure what point you're aiming to make, but yeah, school children are taught a limited view of topics and when they start learning higher level versions of the subjects it becomes murkier and depends on what you're talking about. In physical terms you can't subtract five apples from three apples because there's no such physical thing as a negative apple, but if you're looking at it from an accounting perspective you can say you have -2 apples because you owe someone two

[@glitchnz]

Further to simplifying subjects into discrete boxes, we do the same with 'truth' itself, ie we like to think of 'scientific facts' as right or wrong. The truth is always a lot more complicated, there is no objective way to categorize animals, because the universe simply doesn't do this. So the 'correctness ' if any taxonomic system is entirely subjective and depends on context. It is no more useful to say 'animals are not simply just warm or cold blooded', than it is to say 'real pizzas don't have pineapple' KZbinrs play on this to form click baity titles, as it allows them to justify saying something a lot of people believe to be true is actually false. The reality is that it is not objectively true or false, rather, given a particular context it is more or less accurate. We teach children less accurate descriptions of the world as it makes it easier to grasp certain concepts more quickly, this gives schools the opportunity to teach a broad range of material instead of spending large amounts of time focusing on specialized subject material that may be of no use to a given child in later life.

[@WanderTheNomad]

Loved the greater message about resisting the human tendency to see things in black and white

[@idioticlight]

All my homies hate binary systems

[@deleted-something]

Yea

[@poenpotzu2865]

So would their be a spectrum based system between conditions of life and death. Or is that one of the few actual binary systems?

[@idioticlight]

@@poenpotzu2865 id say spectrum. Viruses are confusing and when somebody dies is arguabel from heart stopping to brain activity mostly ceasing to completely ceasing.

[@martinsmolik2449]

Parallels with human gender are quite obvious. I will show this video to my trans-denying friends, as a gentle introduction of non-binarity of most things natural.

[@andrebenites9919]

I remember looking at similar discussions when talking about "mesothermic" animals (which really means, they are "in between"/in the median between endothermic ("warm blooded") and exothermic (cold-blooded). On that category (mesothermic animals) there are some species of fish with high metabolism, some dinossaurs (which makes sense, since they are between reptiles (cold-blooded) and birds (warm blooded). And it is a lovely way to point out how speacially in biology, there are many cases that don't fit our categorizations perfectly, and also a very large number of different strategies for the same goal.

[@alveolate]

not a biologist, but i suspect the term 'mesotherm' will end up mostly being a placeholder for outliers rather than an actual formal category -- since the entire category really should be refined anyway. it feels like a stopgap to help folks who're stuck in the old paradigm move on to the more accurate understanding we now have. mainly because... almost every animal with some deviance from the old hot/cold-blooded paradigm could be considered a mesotherm.

[@lonestarr1490]

"Whatever you think of as a dichotomy is almost always a spectrum." (John Green)

[@jkjkrandom]

As with most things in bio it's a spectrum not a binary.

[@jkjkrandom]

@@alveolate there are a bunch of terms under mesotherm for different specific types, like there's one for what bears do, one for what tuna do and more I can't remember rn

[@SouthernEli]

Dinosaurs aren't between reptiles and birds. Birds are theropod dinosaurs that managed to be the only dinosaurs that survived the KT extinction to the present day.

[@MrARock001]

I was suprisingly old before I learned that "carnivores" don't actually exclusively eat meat. Even the frightening term "hypercarnivore" just means an animal that gets more than 70% of its dietary requirements from meat.

[@MD.Akib_Al_Azad]

Wait what? I thought they only ate grass to fight parasites

[@hamzahkhan8952]

wait, they don't? i thought their digestive system could not properly handle (large amounts of) plants? also, where do they get the other 30+% of their dietary requirements?

[@teaartist6455]

@@hamzahkhan8952 Plants themselves are a very vague category in terms of describing the nutritional value offered by various parts of plants. For example, nuts, tubers or berries are not the same as leaves or grasses in terms of how easy it is to gain energy from them and what kind of energy they provide. One of them has fairly accessible energy in form of starches, sugars or oils, the other has very little energy that can be accessed without specialized symbiotic bacteria like cows and such have. Think eating salad leaves vs. eating bread and peanut butter. (One may even argue for splitting up plant eating the way we have split up eating meat vs. eating plants into eating parts of plants with very easily accessible energy mostly vs. eating a lot of roughage.) A lot of facultative carnivores (that is, animals that get a lot of their food from meat but that aren't hyper specialized for it) (Depending on how specific you are they may also be called meso- or hypocarnivores) like foxes and bears would eat a lot of berries, fruit, tubers, seeds as well as flowers and fresh, tender shoots (so, a lot like us, just with a bit more meat). A lot of these are comparatively high in fairly easily accessible energy or, in the latter case, may provide other benefits (like micronutrients). There's also the issue of insects sometimes not being considered "meat" or "animals" for reasons that are social rather than scientific, which further muddies the waters. (Though in terms of comparison, it makes more sense to compare obligate carnivores to more run-of-the-mill ones than "Hypercarnivores" since the latter describes an animal that gets most of their nutrition from the meat of other critters - which is to say, a pattern in dietary habits rather than a limit - while obligate carnivore describes one that is unable to get much nutrition from many/most of the plant sources they would have available to them at all.)

[@Manuel73618]

​@@hamzahkhan8952dogs loves nuts and grass, for example

[@hamzahkhan8952]

@@Manuel73618i didnt know that. thx for the info

[@zenebean]

Life is all spectrums and complexity. Our tendency to put things into hard categories is a useful tool when first learning about something, but then too many never embrace curiosity to look closer and see how fuzzy those boundaries are.

[@oliverwilson11]

It's a useful tool at all stages of learning about something. The process of embracing curiosity and looking closer is really just the process of dividing things into finer and finer categories

[@jasonreed7522]

I think of it like light and color, sure the truth is that light is just electromagnetic radiation oscillating on a continuous spectrum of frequencies and the colors we see are a result of the precise mixing of these frequencies. But that doesn't make it less useful to slap some broad categories on it for things like red, blue, radio, UV-A, ect. Both for teaching how to describe the world, and for knowing what effects wavelengths in the general category's range will have. (The difference between blue 450nm and 451nm is basically imperceptible, but between Blue and UV-C is very important as one lets you see and the other gives you cancer) Basically I don't see a reason why just because something is a spectrum we can't also put some categories for parts of the spectrum as those categories are useful even if lacking in some of the nuances.

[@Merlincat007]

Yep. Many get close-minded. Gender and sexuality are prominent examples. Many people learned as kids that there are only men and women and that it's only normal for them to love heterosexually - and then they took that as gospel and refused to follow our changing societal awareness.

[@murph_mustela]

Can I ask, were you into Guardians of Ga'hoole as a kid?

[@zenebean]

@@murph_mustela good stuff, but it did get weird as the books kept going. Owl magic is intricate stuff. Wish more movies looked as good as the one it got

[@afhdfh]

That's why we call them poikilotherm and homeotherm nowadays. One group relies mainly on their metabolism to keep their core temparature a certain heat for long periods of time and the others don't. That way, it's quite easy to categorize them into these two groups.

[@adrianblake8876]

The terms you gave are actually the vertical axis of the chart, so a sea turtle is an exothermic homeotherm, while a hedgehog is an endothermic poikilotherm...

[@Archimedes.5000]

It's literally just different words for the same thing...

[@afhdfh]

@@Archimedes.5000 no, they're not. Look up the definition and be surprised. ;)

[@Archimedes.5000]

@@afhdfh *Endotherm:* organism that gets most of it's heat from internal processes (implicitly having control over them) *Homeotherm:* organism that can maintain it's temperature in wide range of outside conditions (implicitly producing most of the energy) So yeah, same thing. The reason why "homeotherm" is the preferred term for some is because "endotherm" conflicts with the thermodynamics definition

[@Alveonadra]

Finaly someone who understands biology

[@luketurner314]

I think a part of this is keeping things simple for younger children that might not be ready for the nuances of how things really work. Similar to the topic of an episode of StarTalk about the shape of the Earth: a sphere, but more specifically an oblate spheroid... that's not perfectly smooth because of mountains, valleys, and such. I think it's more a matter of resolution and specificity. But, as adults I agree it is not a good idea to continue thinking things are as simple as black and white

[@ruolbu]

Which is where the problem lies. Our minds are less flexible as adults and the further we push back learning the intricacies of reality the more you get people who are just unable or unwilling to adjust and relearn. I think it's valuable to teach kids that things are complex from the get go, as long as there is no expectation that they have to get everything right. Boiling it down is fine, but the occasinal reminder that everything is not that simple really helps trains kids to be more open minded about new topics later in life.

[@theangrysuchomimus5163]

@@ruolbu I don’t think it’s such a good idea to teach complex topics to kids from the get go. Like imagine trying to teach algebra and calculus to a 6 years old or asking them how thermodynamics works.

[@CamoEnjoyer]

Disagree that splitting animals into cold-blooded and warm-blooded is particularly simpler. Saying that animals vary in how much heat they produce and how much their temperature can change isn't particularly more difficult. Simlarly, saying that Earth is "pretty close to" a sphere would be simple while also being true

[@no_bitches420]

​@@theangrysuchomimus5163 Math is different from biology though. You need to first learn basics to understand calculus and other things. With this example of warm and cold blooded animals, it would be easier to teach about it being more nuanced from the start. It isn't very hard to understand that Marlins would like to keep their heads warmer than the rest of their bodies.

[@Fred-tz7hs]

The earth is the most sphere like object on the planet, that's how smooth it is. Calling it anything but a sphere is like denying the existence of geometrical objects in general. If earth is not a sphere, it may as well be flat

[@hangukhiphop]

I think the categories are still useful because cold-blooded animals haven't evolved an endocrine basis for body heat, in the hypothalamus to be exact. Any cold or warm-blooded animal can boost their body temperature by exerting themselves, so the bee and fish examples don't really check out. Also there's value in simplification, which comes at a very low cost in this case. It's just not efficient to approach this in granular terms unless your job depends on it or it's for hobby's sake.

[@jimmynesbit1803]

I don’t know much about the other animals but I know for a fact sea turtles can get cold stunned basically hypothermia in waters below 10C so witch isn’t that cold at all for water. So I don’t understand where he got the information that their body temperature doesn’t change in colder bodies of water.

[@PixJunior]

​@@jimmynesbit1803jump in a cold water pool and see if your complex body wont get hypothermia

[@Fernando_Cabanillas]

I think that while it is true that it is true that things rarely fit into 2 absolute categories, this video misses the point in the classification of warm-cold blooded animals, which is their ability to generate enough heat internally to passively regulate their temperature. Some of the examples such as with penguins and hibernating animals is taking one characteristic of specific animals and using it to refute "disprove" a specific different characteristic. I agree more critical thinking is needed, but i disagree with this video.

[@Gandhi_Physique]

I wasn't really thinking much but I think I agree. It isn't so much than animal temp fluctuates, it is a question of can the creature produce it's own heat or not? There is some grey area though as evidenced by the creatures that shiver to warm parts but the rest is up to environment. In a lot of cases the dichotomy works though.

[@Appletank8]

it would depend on their environment, wouldn’t it? A human would look cold blooded to a polar bear in the artic.

[@Gandhi_Physique]

@@Appletank8 Uh, no. People would still produce their own heat, it just wouldn't be enough to stop them from dying.

[@Fernando_Cabanillas]

@@Appletank8 in a sense, yes, yet at that point we are going into extreme cases and taking creatures out of their regular habitat

[@johnsober]

Yeah, like warm blooded and cold blooded isn't about actual temperature of the animal (bears an hedgehogs in this video) as much as it is about _how_ they regulate their temperature (warm blooded animals produce it). And using the naked mole rat, the tuna and the bumblebee are more commentary on the fact that all categories animals don't fit into one box which isn't exactly news; I'm pretty sure I've always had to learn about exceptions to rules or trends. I get the sentiment of the video, but they kinda chose a pretty bad way to exemplify and illustrate that sentiment.

[@LukeAps]

Simple categorisation is needed to allow people to communicate quickly and efficiently. Not everything is a damn failure.

[@RCynic75]

Man, what a satisfying video for someone like me who always wondered why this distinction felt so arbitrary to me.

[@SirFloofy001]

I was taught warm blooded were animals that produced enough internal heat to not need external heat normally. Cold blooded animals still produce heat just not quite enough all the time.

[@Swagpion]

That makes sence, and I thought of making a similar comment, but saw they put 2 boxes for diet and had to make a correction.

[@Neme112]

Well, even warm-blooded animals need external heat. For example, we can't survive in freezing conditions. Yes, we can generate internal heat, but only a certain amount. So I'd say the only question is *how much* external heat an organism needs, and that's a spectrum, not a yes or no.

[@juanausensi499]

@@Neme112 Exactly. And every animal produces some internal heat.

[@CGaboL]

As someone who had a hedgehog as a pet recently (sadly passed away of wobbly hedgehog syndrome a few months ago). Placing hedgehogs high and to the left sounds about right.

[@SupaDanteX]

Ah yes, the good old "What you learned 3 years ago was kinda mostly wrong, please allow me to clarify", repeat multiple times through schooling stages / levels / grades.

[@bruh1_11]

I mean that's how education works. You start with simpler concepts even if they aren't entirely correct. People figured it would be a better way to educate kids then straight up facing them with college level science. Imagine trying to teach a kid that doesn't know anything about atoms, the hybridization theory.

[@Mostlyharmless1985]

The last bit, i kinda disagree on. It is useful to relate an animal to how it's environment affects it. It's pretty crucial if you keep things like fish or reptiles.

[@dex6316]

And how does that relate to being warm/cold-blooded. As a human I can only survive within a relatively narrow temperature band without external thermoregulation aids. Maybe you just need to know the environment that an animal thrives in when making an artificial habitat for it.

[@Mostlyharmless1985]

@@dex6316 it relates to cold and warm blooded animals in that a 68 degree house is more than comfortable for you but deathly cold for tropical fish because while you use your metabolism to maintain the proper body temperature in 68 degrees, a tropical fish can not, because it is cold blooded. I really hate having to explain the very basic idea being expressed here to glasses pushing “well ackshually” nerds. It’s a generalization and a useful one at that.

[@Gandhi_Physique]

@@Mostlyharmless1985 I am not comfortable in 68° house lol. 74° is good though. I am meant to hang out with my tropical fish brethren lol

[@JoeTaber]

Great exposition on the range of animal body heat strategies, I'm surprised at the complexity and diversity! But writing off categories altogether throws the baby out with the bathwater; categories can still be *useful* even in the presence of exceptions. It all depends on the level of resolution and your expectations. A better perspective would allow the categories to exist and provide useful generalizations to people that only require a coarse resolution description, while noting that there are exceptions and the categories get fuzzier as you look closer.

[@alveolate]

sure, but the actual definitions of warm/cold-blooded just have a strong tendency to mislead non-specialists. this basic terminology is still taught at grade school science, which may lead to unintended consequences, like children having a sort-of built-in bias against reptiles as pets because they're "cold-blooded", or parents thinking they need to leave warming pads on overnight for reptile pets to "help" them (they can overheat and lose sleep, which would rapdily deteriorate reptile pet health). we can start with these terms/categories, but immediately follow up with clearer explanations. the reality is that the whole warm/cold-blooded dichotomy has been taught to so many generations of the general public that most adults probably still have the wrong idea about it. the need to clear up these misconceptions might be greater than the need to keep the bathwater baby.

[@zacozacoify]

I agree that simple models/simplifications are often helpful and shouldn’t be avoided completely.

[@KitagumaIgen]

Yes exactly - because a 3 minutes and 35 second long explanation is far far far too complex and totally impossible for an 8th-grader to grasp.

[@qwertyTRiG]

The map is not the territory: if a model isn't simplified, it's not useful as a model.

[@KitagumaIgen]

@@qwertyTRiG True, we should always remember that "all models are false some are useful", or to paraphrase Einstein: Everything should be made as simple as possible, but not simpler.

[@Arrowhead311]

Happy Halloween

[@MinuteEarth]

Hope you had a spooktacular night!

[@Arrowhead311]

😂😂

[@LeonardChurch33]

You guys really understand your audience. That first frame is a nostalgia trip.

[@waxkun]

I'm fascinated with the amount of kindergarten teachers that came here to comment why is it better to teach children in simpler ways. You really know your audience 😂 Keep the good work! I loved it

[@hebercluff1665]

Cuz it's kindergarten.....

[@alexy5611]

Kindergartners are kinda dumb

[@reddytoplay9188]

@@gaelurquiz5755 yes, but its children. If you blast all that knowledge to someone then they wouldn't understand a single thing. The problem is how this knowledge never gets corrected in the internet, not that it exist.

[@dex6316]

@@reddytoplay9188 maybe teach them that different animals have different strategies to maintain their body temperatures. Some like humans rely primarily on internal heat generation. Others like generally reptiles rely primarily on their environment. Some animals use a combination of the two, and some animals have different temperature zones for different parts of the body. Human core temperature is about 5*C hotter than extremity temperature. Accurate, simple, and quick. No need for this oversimplified binary nonsense. Most things in biology fall along a spectrum, so kids should be taught that there is an in between.

[@SuperElephant]

Wow! I really like the categorization by multi-dimension analog chart! Really good explanation for easy understanding!

[@cfv7461]

I remember the Idhun saga. Cold blooded serpents with ice power. Solid grasp of biology right there.

[@Avabees]

Generalizing is good for long term memory. Just because some animals are blurry in their method of thermoregulation doesnt make cold and warmblooded useless terms, just misleading

[@Marewig]

All models are wrong, some models are useful. This just falls into the category of yet another model that we humans use to make sense of things.

[@hoptanglishalive4156]

Would it be cost-effective to throw out my old oven and buy a bunch of bees to cook my dinners?

[@ranimeRAT]

If you can train them 🤔

[@grigoriskapr]

Pretty sure I saw this video with at least 3 different thumbnails throughout the past few hours. Hope it's just the standard experimenting and not a sign of a bad upload. Anyways, thought I'd give it some love 'cause you guys deserve it for all the amazing work you do and interesting animal (and more) facts you've taught me!

[@VcSaJen]

It's the latest clickbait meta. Was popularized by Veritasium.

[@billyfox6368]

I feel as though you're making videos on my A-level biology topics. 😂 The last few have aligned just neatly.

[@FrazerKirkman]

Clear, succinct, insightful and productive shifting! Thanks for such a great video.

[@mm-yt8sf]

the other axis i've wondered about is where different animals feel "comfortable/uncomfortable" i assumed that cold blooded didn't feel it much but now i'm thinking maybe i can't just assume a lack of agitate response is an indicator of discomfort. i suppose if i had a pet i could try exposing it to two temperature zones and see which produces marked preferences even in the presence of distractors like food. since they can't complain i'd want to know they're probably comfortable in a given setting.

[@DanaTheLateBloomingFruitLoop]

I had no idea how complex this topic is! I was aware that some animals are called mesothermic, neither endothermic (warm-blooded) or exothermic (cold-blood), but this just breaks the mold entirely!

[@kevincronk7981]

I've heard of how most dinosaurs were mesothermic, aka somewhere too far in between to try to label them as either cold or warm blooded, and in my own life I've noticed my cats, while definitely warm blooded, are good at absorbing heat and then just producing whatever amount they still need to keep their temperature consistent, hence why they love warm people things and places, but we humans aren't like that. If our environment gets hotter, we just overheat and have to get rid of the excess. Now this does eventually happen with cats too, but they have a pretty wide range of flexibility. Also just to make this fully clear this is entirely my personal observations of my 2 house cats compared to humans, this is by no means scientific or a large representative sample size or anything of the sort.

[@tosehoed123]

Interesting hypothesis. What makes you think they do this? Have you tried using a thermometer to corroborate this? Actually though, it seems like something a cat would do, lazy as the can be at times

[@Just_A_Indian_Dude]

Keep up your good work 👍

[@Stormer13]

To all the people asking why you weren't taught this in elementary, answer me this: assuming you aren't in a field where the temperature regulation of animals is actually a vital part of your job (so vets, zookeepers, ecologists, and various subcategories of biologists with specializations in this please don't answer), how often do you think of this for your day-to-day life? How often do you need to apply these concepts to your job? My wager is not often to never. We, as hindsighted commenters, often try to point out examples of "how your elementary teacher failed you" without actually pointing out examples of how to improve education. We fail to realize that teaching isn't about giving children every little bit of information about every subject known to man before they graduate. We fail to acknowledge that the majority of kids won't use a good portion of what they learn in large classroom settings on an everyday basis. We think teachers need to be able to give every kid their full attention, much like private tutors of olden days, when they only see these kids for 6 to eight hours a day and they're seeing thirty to sixty students at a time (and that's on the smaller scale). We get offended that we didn't learn something we're only going to forget in a month or so, like it was truly a big deal that warm-blooded and cold-blooded are actually just simplifications used to help explain a concept in science almost none of us will use on even a cool-fact-for-parties occasion. We do this for all manner of subjects, then complain that students shouldn't need to take calculus in high school because "you don't use it anyways unless that's your career" (ok, I may be a little biased because I like math, but the point still stands). Instead, we should consider how we can make education better and more efficient. Figure out what skills will be needed and useful for everyone (or at least the majority of everyone) in the future and teach those. Skills like money management, problem solving, writing and language, how to do your own deep dives into topics you're passionate about, etc. After, we introduce basic concepts for a lot of different topics so that students can later engage more deeply with those topics they're interested in, be it through trade school, college, apprenticeships, or going straight to the work force. These concepts may and should be simplified, both to maximize the possible breadth of the pool available and to further encourage genuinely driven deep dives into those subjects. In the end, if you only read the last paragraph of my rant, think about this: it's okay to understand some things in black and white ways. As long as you realize there is a possibility of that thing being much more complicated than the black and white explanation, you're doing okay. No one has to know everything about everything. I don't need my mechanic to know that there is actually a spectrum of warm-blooded and cold-blooded animals, just how to fix my engine.

[@quokka_11]

There are beings who try to separate everything into two groups, and then there are those who don't.

[@Brett.D]

So there are still 2 groups 😉

[@terrybuckley2850]

Got’em

[@FelanLP]

I grew up with "wechselwarm" (alternating warm in German) instead of "cold blooded".

[@barbnoren]

elementary school STEAM teacher here: i'd love to see a video about why we educate the way that we do, starting with simple models that aren't entirely accurate and increasing complexity along with the developing brains of young humans. for instance, it's important as an educator to note that a preschooler has a wildly different ability to comprehend simple categorization than a 1st grader, due to neural development. a 2-dimensional graph like you show would be lost on most below middle school. teaching with simple models isn't lazy education, it's providing the framework for greater complexity later on. and it would certainly be nice to not have to look at the comments and see people suggesting that we teach kids as though they were "dumb" rather than in a developmentally-appropriate manner.

[@Gandhi_Physique]

I think it is a mix of both tbh. Some teaching methods/teachers are mediocre, but some subjects need simplification to some extent. You don't start with multiplication, you start with recognizing numbers. I will say though, there is a reason my niece and I were well above the other kids. She is in elementary, but frequently gets commendation for being so advanced. It starts at home, with parents/siblings showing the kid how to do stuff and showing them learning is fun, starting very early like 2 or 3. I always showed my niece cool things that could be done with numbers and weird facts. I even told her about nuance at times. Sure she doesn't quite understand atoms, but she is aware of them and how insanely tiny they are. I tell her important parts and also some other stuff she won't quite understand. She likes to learn because we made it fun. I virtually never studied even through my college degree, and my niece will probably actually study. She had a better upbringing than I, but nonetheless my dad did a similar thing with me when I was tiny and it showed through my school performance. School is a joke in America, but at the same time when parents expect schools to do all the work then maybe school isn't so bad.

[@wizardsuth]

_All models are wrong but some are useful._ -- George E.P. Box

[@dragonturtle2703]

There is a third reason: because as long as something is true more often than not, and you don’t hold it as an absolute, it’s better than just “it’s complicated”.

[@petelee2477]

Or here me maybe instead of teaching kids in absolute terms just make it into a spectrum.

[@dramaqueen4640]

Good video, learned a lot.

[@MisterMakerNL]

Good points, I am glad I learned something new today, thanks!

[@shoam2103]

So there's still a spectrum, and it can be mostly categorized that way, with exceptions? Just have to keep in mind animals have lots of interesting strategies for temperature regulation. Like just being big for example.

[@djj949]

interesting, love the breakdown

[@elenafoleyfoley168]

Excellent video and information thankyou 🙏🏻

[@electronresonator8882]

how about "self-regulated" and "adaptive" ?

[@thoraero]

Good stuff. Thank you.

[@alexg4711]

i mean it makes sense to label things in easy terms. in basically every field you will learn that some simplifications are wrong if you look closely. but simplifcations are just that. they are here to make things easier to understand for people that have no real need to know every little detail.

[@LCCWPresents]

Best way to think about it is like a motorcycle. Warm blooded animals are like oil cooled engines, which depends on the amount and quality of oil to cool the motorcycle versus air cooled engine which will stay warm enough to run when running but have a little more reliance on the air to cool the engine instead of oil.

[@okkomp]

Now I need to do a course on motorbikes too?

[@blackcid]

You mistook "being unable to generate your own heat to keep your body running and depending on the environment" with "oh, this animal changes temperature, that's why it's not warm-blooded." WTF

[@PhatatNguyen-lx5dy]

He did not say that. he said why does this so called warm blooded, who is supposed to have a consistent temperature, changed body temperature during winter(or some other time) or only somepart of them change the temperature

[@PhatatNguyen-lx5dy]

You should watch the video again, he also clearly stated that there are cold blooded animals that cant generate heat and they also depend on the environment and other aspects

[@wizardsuth]

1:13 "Immediately you can see things get even more complicated." -- Yes, far too complicated. A simple model that works in most cases is better than a complicated model that tells you nothing useful in any case.

[@helloeverybody9675]

The two categories still hold true. This is just being super specific.

[@DaveTexas]

Why would you NOT want to hibernate? I would absolutely love to hibernate from mid-May to mid-September! I hate summer. I hate not being able to go outside because it’s 105° every afternoon. I’d rather just sleep through it - and wake up skinny in the fall!

[@ricardoludwig4787]

I knew this beforehand but struggled to explain it to other people, you truly are great at explaining things in an easy and concise manner

[@crtlaltoption]

Learning about complexities I previously didn't know about is my favorite way to feel like I really don't know anything

[@skeletonwithguns3786]

This is channel is like my favorite bio teacher

[@kyletorfin]

Isn't it called the Pacific Crest Trail?

[@mywifebeatheroin]

There's no such thing as hot or cold drinks because I didn't finish my coffee

[@roccothegoldie9380]

these r so good!

[@lewismassie]

I once took a very extensive rabbit hole into the different kinds of mating behaviour among animals. Was very interesting, and extremely varied

[@FlightingVagner]

This video has the highest concentration of science wisdom per minute I even seen!

[@purplenebula8451]

The hyena one is not correct tho

[@kevinleugan6037]

This is the same as the whole 3 states of matter thing. Most people who never go beyond elementary physics will only know about solid, liquid, and gas, but those who have learned a bit more science will probably be able to name plasma as a 4th state. But talk to an actual physicist and they'll start naming a dozen primary states of matter and dozens more subcategories. For the most part, people only need to know about the 3 to go about their daily life and have an passing scientific understanding of how things work. Obviously the "truth" is much more interesting, but it is also much more complex and confusing and not something the average person would want to or need to deal with.

[@viralengine908]

So some animals are capable of generating their own heat and some rely on the environment. I don't see what's been disproved here

[@dhruvpatel.1001]

Humans wants to perceive everything in Black and White, reminded me of the Organic Chemistry where you get to have more exceptions than rules to describe them!

[@bentoney9682]

The spectrum makes sense but are the examples listed more so outliers and most do fall heavly on 1 side of specrtum?

[@Scrogan]

Ah, a “follow the facts” imperative, haven’t had one of those in a while!

[@pavangaonkardonigadde]

Nice video thank you 🙂

[@NetRolller3D]

I think a better division is between metabolic regulators (which actively change their metabolic rate, either up or down, in response to a temperature change) and nonregulators (which allow their metabolic rate to shift based on thermochemical effects alone). This is not only a binary classification, but it also retains a primitive vs. derived distinction, while staying consistent. For example, a hibernating hedgehog senses the temperature going down, and in response, actively slows down its metabolism more than what thermochemistry predicts, which is a derived/evolved trait, and is more similar to a human speeding up metabolism in response to cold weather than to bacterial metabolism slowing down as a consequence of lower temperatures. Under this distinction, humans and hedgehogs are both regulators (with very different regulatory strategies), while bacteria are nonregulators.

[@nedisawegoyogya]

I thought we already moved trom warm-cold blood classification to endothermic vs non endothermic classification which has discrete evolutionary history by looking at mitochondrial uncoupling protein (UCP) and brown adipose tissue huh

[@PixJunior]

Evolutionary what? Im biologist and i can assume to you its not such thing as cold-warm blood in any phylogeny ever

[@nedisawegoyogya]

@@PixJunior explain birds

[@PixJunior]

@@nedisawegoyogya birds evolved from sauropsids, a sister clade to synapsids, wich evolved perpendicularly to mammals, whom are also considered "warm blooded". The point is that there is no such thing as defining warm blood as a evolutionary parameter, its the same as considering coelomates to define if something is "newer" than something. It was cool past times but today evolution is ruled by genetics, and genetics says otherwise about parameters like endothermy.

[@nedisawegoyogya]

@@PixJunior explain ucp gene

[@petersmythe6462]

Even humans allow their extremities to fall to very low temperatures compared to their core. The bulk temperature of the arms and legs can drop far below that of the head and thorax especially in cold environments. And moreover this isn't simply the body failing to keep up but deliberately allowing the more cold-tolerant bodyparts to cool to temperatures that would be extremely dangerous if they were in the core. I tried making a system to model body heat and metabolism in a game and actually found that to get reasonable results for both cold and hot environments, I had to split an organisms' mass and surface area into core and periphery, with the periphery subject to much looser thermoregulation constraints and its behavior not harshly affected by temperature. Even to get reasonable results for humans. You cannot accurately model human thermoregulation without accounting for the fact that our arms and legs are only sometimes warm (when we need to lose heat).

[@szkoclaw]

I'm sorry, did you just deliberately confuse 'regulated temperature' with 'stable temperature'? Yes, hedgehogs and bears get cold in the winter, but that's because they want to get cold and they can stay at a consistent temperature during hibernation.

[@samhodge7460]

Yeah, this video is kind of garbage, tbh.

[@rhobidderskag1121]

Being able to tolerate large fluctuations in body temperature is such an advantage. Humans can even be induced into it, but it usually requires outside medical help to prevent the body from hurting itself. When you successfully get a human body to hibernate, we can survive far longer without food, water or even air, and you can delay tissue death as the result of injuries, blood loss, or exposure. In fact the only thing preventing you from taking the extra step and freezing humans for indefinite preservation is damage caused by ice crystals and the impracticality of filling the human body with an anti-freeze agent, something you can do with smaller animals in a lab setting. (Yes you can in fact resuscitate frozen small animals provided you freeze and rewarm them properly; it’s actually what the first microwave was invented for)

[@kvd1]

To animals that have mixed warm blooded and cold blooded traits will be called poly blooded animals. Emperor penguins(and their cousins) have evolved cold blooded feet, to avoid using more energy to warm up their legs, and save that valuable energy for making their own eggs and for surviving the harsh winter environment of Antarctica, and thus avoid trying to melt the ice underneath them(if the feet are heat productive and they can melt the ice).

[@MelvinDorkus]

I always wondered about this, ever since seeing a cat sleeping on a window sill for 12 hrs a day.

[@Aurochhunter]

This is 10th grade biology class all over again.

[@crpineo]

0:22 2:10 _"...two buckets."_ Friend, those are boxes

[@kimemia_maina]

Maybe it is because it makes the material easier to deliver in an education syllabus?

[@fenhen]

Short version is it’s another example of people trying to categorise things in easy to remember boxes, whereas the reality is that nature is messy.

[@brunobastos5533]

A video how to be wrong , bees can heat up but that is different, hot blooded mean that your body metabolism generate heat even standing still , then come with hibernation to state that mammals aren´t hot blooded , hibernation in mammals is lowering is metabolism to survive the winter , and fever really , that a strategy to fight diseases like swelling. And turtles still cold blooded because theirs metabolism can't generate heat that why you dont have them on colder waters and being big just mean they got a bigger heat inertia mean that heat slow but also lose it slower. And pinguins keep is feet cold so they don't waste energy heating them .

[@LordOmnit]

It would probably be best to include a third axis on that chart to indicate whether or not a given temperature variance strategy is voluntary or involuntary. The example of a fever causing variance in human body temperature is valid, but the fact it is essentially not a choice seems like it's another important factor in the nuance. Although I am certain that whether or not some strategies are voluntary or involuntary will get heavily debated when talking about nonhuman animals.

[@alunjones3860]

Increasing body temperature in response to infection is common across the animal kingdom. Cold blooded animals seek out more heat when sick. It's because the immune system works better at higher temperatures and many viruses and bacteria don't.

[@WCOBDisorder]

A curse on you for releasing this the day after I teach endo and ectothermy to my students.

[@WangleLine]

That's so interesting!!

[@will2003michael2003]

Ummmm, I’d say in general the distinction is still a good description. Penguins having cold feet doesn’t really throw off the paradigm.

[@roccothegoldie9380]

dont stop making these

[@rextanglr4056]

Once again, it is not just one or the other. It's more like a spectrum. No, like a graph. This is getting more complex when you think about it... ...just like complex numbers.

[@danilooliveira6580]

a color coded 3 dimensional graph, when 3 axis aren't enough.

[@iamgreatalwaysgreat8209]

Imaginary numbers

[@jeeves744]

Sorry, the catagories still work. Just because everything doesn't fit 100% perfectly into them doesn't change that fact. If someone has brown hair then suddenly has 1 grey hair would you suddenly say that person no longer has brown hair and make up a new catagory? No you wouldn't.

[@Exile_Sky]

The split categories are a matter of simplistic priority. What is a thing "mostly" over what is a thing "actually". "Mostly" is good enough to understand what a thing is for the majority of its existence so it is a "good enough". "Actually" takes up the brain with information that won't lead to "survival" or "reproduction" so most if it is thrown out or deemed "unimportant". Simple as.

[@sandis550]

Dude the penguin example is just ridiculous, even people in the winter have body temp of 37 °C and feet/hands temperature of 25 °C, what should matter is average body temperature

[@ImmortalAbsol]

I didn't know fluctuation was part of the definition, I guess that's why the concept worked slightly better in my head than it actually does.

[@Archimedes.5000]

That's because the video is lying. The fluctuation is indeed part of the definition, but no one sane says that bear is cold blooded because it hibernates...

[@porcorosso4330]

The categories are a generalization. It's not wrong, but it wouldn't hold true for all cases. There are bound to be special states or in-betweens. It is merely a communication tool for us to for us to compare and contrast both animals we have seen and have not seen.

[@CalculusDaddy]

Are there any things we learned in elementary school that isn’t technically “wrong?”

[@GuzikPL4]

Nice video, but the argument with cold penguins feet is the stupidest thing i heard today

[@sunMMVIII]

Historical inertia

[@Greyglasses232]

What is it that makes the heat in animals? Is it from chemical reactions in food or moving muscles or something else?

[@archtansterpg4246]

Reminds me of how we tend to list only five senses, even though we have more (by some counts, over 20 or so?) Because things like sound, sight, and taste easily map onto visible parts of the body (like, how are you going to teach a 5-yr-old about proprioception?). Sometimes we simplify things based on the target audience.

[@danielovercash1093]

Historical inertia is a very underused term

[@velosepappe]

Nature is inherently extremely messy and just weird, and in order for humans and many animals to make sense of their surroundings we developed these boxes. It's a way to quickly make the distinction between safe and dangerous. One could be aware that every box that exists is only that, a grotesque simplification of reality. That every scientific concept, such as cold-blooded and warm-blooded, is only an attempt to describe reality. It's an attempt to make reality comprehendible. It should be judged by its usefulness as a tool: is it simple enough to use versus the value it adds? Simplicity: only 2 options to remember, and broad animal categories that are common knowledge to attribute bloodedness to. Added value: starting point to study biology, useful for pet-caring, some other spurious situations when such knowledge comes in handy. When in doubt, use occam's razor.

[@useodyseeorbitchute9450]

If you think about evolution of our brain, I'd say that actually nature has created the boxes...

[@GiRR007]

Honestly this is just making things needlessly complicated and somewhat misleading. The categories of warm and cold blooded are fine and serve their function well.

[@brandondavidson4085]

I really thought this video was going to tell me that cold-blooded animals don't exist. But I'm so glad that things are nuanced!

[@Swagpion]

2:15 there are 3 boxes in the top right, you missed omnivores, and even then, a spectrum is sometimes used. And it normally is based in the digestive system, not diet. And smarts is almost always represented by a spectrum.

[@LavenderLushLuxury]

Good Video, Minute Earth... 💙💙💙 I always look forward to your, Earth AND Space, Science Videos On, KZbin!!!

[@dtpduran]

Hmmm? We use warm/cold blooded as a stepping stone. This is no different from General Relativity actually disproves or shows that Newtonian Physics is wrong (inaccurate). I asked a professor before why they still teach Newtonian if that is the case and his reply is that you need to know walk first before you run into the deeper concepts and more "accurate" models.

[@ericolens3]

Being warm blooded only works to a certain extent. Hypothermia, frost bite, heat exhaustion, heat stroke can happen to us. We just have better thermal ranges. Exothermic animals like reptiles are bit more rare in cooler climates. Endotherms can better withstand the cold. (Idk if exotherms are more common than endos in deserts, since hot is hot, and it basically boils down to who can best find a cool spot during the hottest times of the day. )

[@fikriasrofi5312]

So its more like spectrum and we classified those thing to make indentification much easier and practical