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The concept of warm-blooded and cold-blooded animals is outdated because there are actually tons of different animal thermoregulation strategies.

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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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David Goldenberg | Script Writer, Narrator and Director
Sarah Berman | Illustration, Video Editing and Animation
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[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.

[WanderTheNomad]

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

[andrebenites]

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.

[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.

[MrARock]

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.

[luketurner]

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

[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.

[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.

[LukeAps]

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

[jeeves]

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.

[RCynic]

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

[SirFloofy]

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.

[Mostlyharmless]

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.

[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.

[viralengine]

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

[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.

[LeonardChurch]

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

[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.

[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

[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