Worldbuilding Consequences Of a Faster Heartbeat

[Spacescifi]

So if you make a scifi alien humanoid and by necessity tweak them since they look human too much already (looking at you Star Trek, and I am laughing at you Superman and Supergirl), what happens if you give them a faster heartbeat?

 

I looked up why birds have a fast heartbeat. It is because they burn more oxygen because they use a lot of energy flying.

Naturally they have to eat more too.

Like to put it in human terms, imagine eating about 22 pounds of food EVERY day.

https://jaysnatureblog.wordpress.com/2015/01/23/eat-like-a-bird-not-what-you-might-think/

Yeah... we don't do that... but birds eat a lot for their body size.

Obviously all that food has to to be used as energy, so I presume that these humanoids with the faster heartbeat may have longer endurance before they tire compared to normal humans... but at the cost of needing to eat a lot more or risk feeling starved snd hangry. The cool thing is they could likely sprint for considerably longer than a human and eventually beat Usain Bolt if the race was long distance... since Bolt would slow and they would sprint past him.

 

Endurance walking is literally what humans are arguably better at than any other animal save insects.

 

So I presume scifi humanoids with faster heartbeats are just high performance versions.

 

Thoughts?

Edited September 29, 2022 by Spacescifi

[Terwin]

More energy does not conflate with endurance.  Smaller  mammals tend to have higher heart-rates but do not always have good endurance.

Higher burst energy probably, but endurance is more than that.

 

Also, heart-rate(which relates closely to metabolic rate) and longevity are somewhat linked, mean-time-before failure and all.  (examples: ferrets have a heart-rate ~5x the human heart-rate and the oldest ones live to about 14 years, cats have ~2x the human heart rate and a few specimens live to be 25-30 years old, while Rabbits have ~3x the human heart rate and the oldest recorded rabbit lived to be 18 years 10 months old, and finally, Elephants have a heart-rate roughly half that of humans and can live to be 70 years old in the wild)   

So flesh and blood aliens with three times the heart-rate of humans might die of old age around 20-30 years old(better than rabbits due to medicine).

 

 

[Gargamel]

Human bodies work on something similar to Boyle’s law, ie, if one value goes up, another should go down.   Faster the heart rate, lower the Bp, usually.   But all that is usually dictated by the ph level of the spinal fluid, which indicates the amount of waste carbonic acid being released by the cells, which regulates breathing rate, and increased breathing rate reduces the ph level, which assumes the cells are being delivered the appropriate amount nutrients and oxygen level. 
 

All of that is to say that if you start messing around with bodily functions in a fictional setting, don’t get specific as you’ll end up creating logical paradoxes, so keep it simple and vague.  

[kerbiloid]

They would have tachycardia.

[Terwin]

If you want super-human but non-human human-alike, just go with the tried and true: Elves

For examples please see: https://tvtropes.org/pmwiki/pmwiki.php/Main/SpaceElves

(Vulcans, Eldar, Mimbari, etc.)

[sevenperforce]

Remember that humans are space orcs. Compared to virtually all other terrestrial life, our resilience, endurance, healing factor, and capacity for accepting diverse sources of energy is utterly unmatched (in the aggregate, not on every individual level). 

[JoeSchmuckatelli]

11 hours ago, Spacescifi said:

scifi humanoids with faster heartbeats are just high performance versions

400 heartbeats per minute was the theory of this film 

 

Tried to find the exact quote - but it's not in the trailer.  MF explains that it's pumping adrenalin to give Wesley greater abilities than most people enjoy 

On this... I'd have liked it better if the filmmaker had used round bullets.  We all know about the curve ball - so maybe snapping his arm around in a supersonic arc could have curved a ball, but unlikely to curve the cylindrical bullet

[NFUN]

they can summon shardblades faster

[Gargamel]

Problem with really fast heart rates, >200, is that the heart can start to cavitate.   If it’s pumping that fast, the atria don’t have a enough time to refill, so they aren’t priming the ventricles, so your output is decreased.   If they’re pumping as fast as @JoeSchmuckatelli’s movie claims, you’re actually not moving anything at all. 

[StrandedonEarth]

Twice the heart rate, half the volume pumped per beat…

Wanna get funkier? Multiple hearts in strategic places around the body! See “Protector “ by Larry Niven for an example…

 

[magnemoe]

4 hours ago, Terwin said:

More energy does not conflate with endurance.  Smaller  mammals tend to have higher heart-rates but do not always have good endurance.

Higher burst energy probably, but endurance is more than that.

Also, heart-rate(which relates closely to metabolic rate) and longevity are somewhat linked, mean-time-before failure and all.  (examples: ferrets have a heart-rate ~5x the human heart-rate and the oldest ones live to about 14 years, cats have ~2x the human heart rate and a few specimens live to be 25-30 years old, while Rabbits have ~3x the human heart rate and the oldest recorded rabbit lived to be 18 years 10 months old, and finally, Elephants have a heart-rate roughly half that of humans and can live to be 70 years old in the wild)   

So flesh and blood aliens with three times the heart-rate of humans might die of old age around 20-30 years old(better than rabbits due to medicine).

Smaller animals has smaller hears so it makes sense that the heart beat faster, Take an cat heart, can not see it be more than 2 cm in diameter. Assume the heart muscle move as fast as an human heart I would expect the heart to beat at least 4 time faster, the muscles are not working harder they are smaller and don't move that fast. 
Now small animals tend to live shorter life as its lots of predators larger than them so it don't make sense to design for an long life. 
Also how long can lions or tiger live compared to cats?  Large dogs live shorter than small one and suspect same is true for cats. 

Humans are long lived for our size, evolution don't care that happen to you after you stop reproducing, except that grandparents are useful for humans including early ones, they could teach the kids and do cam cores like cooking and making tools and defend it. Giving the parents more time away from the kids hunting and gathering. 
So the family groups who was longer lived was more effective. 

24 minutes ago, StrandedonEarth said:

Twice the heart rate, half the volume pumped per beat…

Wanna get funkier? Multiple hearts in strategic places around the body! See “Protector “ by Larry Niven for an example…

Makes more sense, also is redundancy like why you want multiple engines on planes and ships. You can also have hearts for different purposes like some modern warships combine diesel for fuel efficiency then cruising and gas turbines for maximum power. You also want oxygen uptake and getting rid of heat. 
Now you could go crazy like in The Legacy of Heorot grendels, as in basically nitrous oxide boost for muscles, and yes this overheat them. 
https://en.wikipedia.org/wiki/The_Legacy_of_Heorot

[Spacescifi]

4 hours ago, StrandedonEarth said:

Twice the heart rate, half the volume pumped per beat…

Wanna get funkier? Multiple hearts in strategic places around the body! See “Protector “ by Larry Niven for an example…

 

 

Not sure the human body as it is has room for all that extra equipment.

 

An easier solution is to just have a bigger pump (heart).

 

The humanoid would also have to be bigger than a normal human so that their body would have room for a larger heart.

6 hours ago, Gargamel said:

Problem with really fast heart rates, >200, is that the heart can start to cavitate.   If it’s pumping that fast, the atria don’t have a enough time to refill, so they aren’t priming the ventricles, so your output is decreased.   If they’re pumping as fast as @JoeSchmuckatelli’s movie claims, you’re actually not moving anything at all. 

 

I think... if the heart was literally designed for fast beats, it may not even look exactly like a human heart.

The human heart is not designed for this so of course you are going to have issues, but imagine if it was?

 

It could be simply engineering and material fiber strengh of their heart muscle which would have to exceed a human .heart.

Edited September 29, 2022 by Spacescifi

[Nuke]

isn't there a strong inverse correlation between heart rate and life span? a mouse can live a few years, a whale or tortoise, a lot longer. thats still a better mtbf than any mechanical pump you can buy.

[Spacescifi]

8 minutes ago, Nuke said:

isn't there a strong inverse correlation between heart rate and life span? a mouse can live a few years, a whale or tortoise, a lot longer. thats still a better mtbf than any mechanical pump you can buy.

 

Another option that would meet halfway is longer sleep cycles to recover from their high hearbeat lifestyle.

Stay awake for the day, sleep for 48 hours or less.

Best of both worlds.

[Gargamel]

1 hour ago, Spacescifi said:

I think... if the heart was literally designed for fast beats, it may not even look exactly like a human heart.

You still run into issues of fluid dynamics.   You can only move X volume of blood so fast before the pump starts cavitating.  You'd have to come up with a really really funky design that doesn't make sense evolutionary most likely.

37 minutes ago, Spacescifi said:

Another option that would meet halfway is longer sleep cycles to recover from their high hearbeat lifestyle.

Stay awake for the day, sleep for 48 hours or less.

This doesn't make sense in this context.  Sleep is mainly a cognitive thing, and not so much a circulatory thing.   Yeah, there's repairs and such that go on during sleep, but mainly it allows the brain to store info and reset.   

Perhaps, a normal sleep cycle that matches the circadian rhythm of the home planet, but the creature has evolved a fight/flight response that allows for sustained exertions over extraordinary lengths of time.    Then they need an extended rest period, not sleep necessarily, before they're fully ready again. 

Humans survived well because they were relentless predators.   They aren't fast are strong in comparison to other large creatures, but they're always there.   The prey could sprint away and hide, but shortly after, the humans would turn up in slow pursuit, also nagging at the prey.  It's one of the principals of the "Humans are Space Orcs" memes @sevenperforce presented earlier, although I don't think I see that facet of it in that particular link. 

Now imagine a prey species that evolved in an environment that had a similar large predator.   The ones that survived were the ones that could run and run and survive for long stretches without slowing down.  It's breaks down logically if you think too hard about it, but it'd give you a basis for the species.   It'd be less about an insane heart rate, and more about the body's ability to deliver nutrients and energy to the parts that need it, and to manage the chemical waste products until there was an opportunity to properly dispose of it.    On a long run? Then the arm muscles would have the ability to dump glucose (et al) back into the blood stream and absorb the acids that are building up in the system.   You arms would start to burn before your legs would.    Then when you are done with the activity you needed, you would need an extended rest period to recover and do it again. 

Edit:  Heck, an extra organ that does just that would be ideal.   It would dump adrenaline and glucose, and absorb the waste materials.   Have it linked in the circulatory system right before the heart and lungs so it could regulate the amount of carbonic acids in the blood stream more effectively.  

Don't make the heart pump better, make the other organs and the blood better.   Let the blood carry more oxygen than is normally possible (see also: Lance Armstrong). 

Edited September 30, 2022 by Gargamel

[Spacescifi]

24 minutes ago, Gargamel said:

You still run into issues of fluid dynamics.   You can only move X volume of blood so fast before the pump starts cavitating.  You'd have to come up with a really really funky design that doesn't make sense evolutionary most likely.

This doesn't make sense in this context.  Sleep is mainly a cognitive thing, and not so much a circulatory thing.   Yeah, there's repairs and such that go on during sleep, but mainly it allows the brain to store info and reset.   

Perhaps, a normal sleep cycle that matches the circadian rhythm of the home planet, but the creature has evolved a fight/flight response that allows for sustained exertions over extraordinary lengths of time.    Then they need an extended rest period, not sleep necessarily, before they're fully ready again. 

Humans survived well because they were relentless predators.   They aren't fast are strong in comparison to other large creatures, but they're always there.   The prey could sprint away and hide, but shortly after, the humans would turn up in slow pursuit, also nagging at the prey.  It's one of the principals of the "Humans are Space Orcs" memes @sevenperforce presented earlier, although I don't think I see that facet of it in that particular link. 

Now imagine a prey species that evolved in an environment that had a similar large predator.   The ones that survived were the ones that could run and run and survive for long stretches without slowing down.  It's breaks down logically if you think too hard about it, but it'd give you a basis for the species.   It'd be less about an insane heart rate, and more about the body's ability to deliver nutrients and energy to the parts that need it, and to manage the chemical waste products until there was an opportunity to properly dispose of it.    On a long run? Then the arm muscles would have the ability to dump glucose (et al) back into the blood stream and absorb the acids that are building up in the system.   You arms would start to burn before your legs would.    Then when you are done with the activity you needed, you would need an extended rest period to recover and do it again. 

Edit:  Heck, an extra organ that does just that would be ideal.   It would dump adrenaline and glucose, and absorb the waste materials.   Have it linked in the circulatory system right before the heart and lungs so it could regulate the amount of carbonic acids in the blood stream more effectively.  

Don't make the heart pump better, make the other organs and the blood better.   Let the blood carry more oxygen than is normally possible (see also: Lance Armstrong). 

 

Thanks... I had not thought of that.

 

Basically a predator with human like endurance that hunts in literally herd size packs, and the only way to get away is to out run them at a far distance or kill them off or set up spikes or walls or ditches so they cannot reach you.

 

I think by the time the humanoids developed civilization they would likely put the human level endurance pack predator on the endangered species list... much like we did to lions.

 

The human body DOES have space for an extra organ... I dunno... make it an alien kind of appendix lol.

 

EDIT: Extra oxygen in blood lets them hold breath longer too underwater.

 

I think the main cost would be a need for extended rest periods. 

 

But in civilized modern society, they would have no need to run for their lives much.

 

So I suppose in that case they could get by eating less. But when exerting themselves more they would naturally want to eat more.

 

I guess you are saying for a given amount of food their  body uses it more efficiently.

 

What's the drawback?

 

I love drawbacks... gives them a more realistic touch.

Edited September 30, 2022 by Spacescifi

[Gargamel]

5 minutes ago, Spacescifi said:

I think by the time the humanoids developed civilization they would likely put the human level endurance pack predator on the endangered species list... much like we did to lions.

See, I said don't think too hard about it!    

[Spacescifi]

5 minutes ago, Gargamel said:

See, I said don't think too hard about it!    

No... that's just more worldbuilding... still better than outright extinction.

[JoeSchmuckatelli]

2 hours ago, Spacescifi said:

easier solution is to just have a bigger pump (heart).

Famous Racehorses and Huge Hearts! ~ EquiPepper

[Gargamel]

^^^

It's not pumping much faster than any other heart, it's pumping more. 

[Shpaget]

3 hours ago, Spacescifi said:

 

I think... if the heart was literally designed for fast beats, it may not even look exactly like a human heart.

The human heart is not designed for this so of course you are going to have issues, but imagine if it was?

Heart, human or otherwise, is not designed for any particular function or mode of operation. Evolution does not work with a goal in mind. It just happens, and if it works better than the previous version, it tends to stick around.

[Spacescifi]

21 hours ago, Gargamel said:

^^^

It's not pumping much faster than any other heart, it's pumping more. 

 

Hahaha..  so I was kind of on the right track after all!

So... why not use both?

Your idea with extra organ supplying stored nutrients for energy on long sprints. And a somewhat larger heart that can pump more blood at the same normal rate. To get this extra room the ribe cage will be thinner but just as strong.

So I guess the only real downside is somewhat less chest protection since thinner ribs are probabably easier to break..... or not.

I could give thinner ribs but more of them, making it kind of like... internal armor.

Edited September 30, 2022 by Spacescifi

[Nuke]

the giraffe has a huge heart, because its got to pump blood all the way to its brain. 

[Gargamel]

27 minutes ago, Spacescifi said:

So I guess the only real downside is somewhat less chest protection since thinner ribs are probabably easier to break..... or not.

Why would they have thinner bones?  If they have an increased blood supply, an argument could be made for larger bones.   One the fastest, in both obtaining access and administration of fluids, methods for "IV" access was to plunge a large needle into the sternum of my patient.  The interosseous region of the body is a huge blood producer and reservoir for fluids.    Since these creatures would have better circulatory system, then it stands to reason that they would have larger bones to compensate.   And larger doesn't mean heavier per se, at least on a linear scale.  If they're "hollow" for large blood supply (not bird hollow, but human hollow), then the mass wouldn't increase as much as you think.   Throw some hand wavium in there about some natural occurring mineral in their diet making stronger bones (a la replacing steel with titanium in a metallurgy), and you can have bigger, stronger, and possibly lighter bones.

 

And when I say "Large needle", I mean this:

 

If you see me coming at you with this, don't worry, you're already having a very bad day. 

[Spacescifi]

10 minutes ago, Gargamel said:

Why would they have thinner bones?  If they have an increased blood supply, an argument could be made for larger bones.   One the fastest, in both obtaining access and administration of fluids, methods for "IV" access was to plunge a large needle into the sternum of my patient.  The interosseous region of the body is a huge blood producer and reservoir for fluids.    Since these creatures would have better circulatory system, then it stands to reason that they would have larger bones to compensate.   And larger doesn't mean heavier per se, at least on a linear scale.  If they're "hollow" for large blood supply (not bird hollow, but human hollow), then the mass wouldn't increase as much as you think.   Throw some hand wavium in there about some natural occurring mineral in their diet making stronger bones (a la replacing steel with titanium in a metallurgy), and you can have bigger, stronger, and possibly lighter bones.

 

And when I say "Large needle", I mean this:

 

If you see me coming at you with this, don't worry, you're already having a very bad day. 

 

Cool point.

 

I only theorized thinner bones to accomadate a larger heart.... since I was thinking of a humanoid body that looked similar to what we are.... not any larger.

 

More exotic non-human aliens are by comparison... ironically easier to justify and make up their biology.

Edited September 30, 2022 by Spacescifi