In story I'm considering writing, a branch of hominid that had been trapped on another alternate earth after being crossing over through rifts are able to return to our earth after these rifts started appearing again.

These hominids which split from homo sapiens 200,000 to 100,000 years ago are descended from a founder population that had migrated through a rift before it closed. In overall appearance, you would not be blamed for mistaking one of these humans as being apart of our species...

...if not for the fact that they are much stronger than we are.

Some feats that these humans have displayed are:

  • Much higher muscular strength, allowing a single person to toss steel trash can 5 to 10 meters with relatively little effort.

  • Flip a car onto its roof or with a buddy do the same thing with large truck.

  • Carry heavy objects like 100 kg dumbbells around with ease.

  • Have a much higher level of endurance than we do.

  • Be able to run faster and for a longer period of time than we can.

  • Jump and leap three times further than we can.

  • Faster reflexes

  • Survive accidents unscathed that would have severally crippled or even kill human from our world. Such a very bad car or train crashes, or falling from a height that would have broken our bones.

  • Take large amounts of punishment in a fight that would have left a human from our from world out of commission, either from pain, inability to get up due to injuries, or sheer exhaustion.

Overall, the thing you would expect to see happen to characters in a action movie or anime.

Additionally, these feats are displayed by individuals who otherwise look like your average street joe who is moderately fit and healthy, and not someone who looks like a brickhouse. Variation exists of course but above is the standard.

Now these changes do have a physiological bases, though at the cost of very active metabolism that these humans need to maintain by consuming large amounts of calories to keep running. So much in fact that when times are lean, they can enter a state of torpor to conserve energy and prevent starvation for a time.

Some of these physiological changes are:

  • An increase in muscle density per cm3 and a much higher count of muscular mitochondria than we do.

  • Increased amounts of intracellular ATP

  • Thicker and denser bones that appears to originate from a variation of a mutation in the Lpr5 gene.

  • Large amount of blood capillary beds that act as blood revisors for extended periods of activity.

  • A more efficient respiratory system.

  • The front portion of the skull i.e face, is much thicker than ours with a appropriate reduction in brain size. Though curiously it has appeared to compensate for this by being more complex than our brains, resulting in comparable levels of intellect.

  • Enzymes in the blood that breaks down lactic acid far better than our bodies can.

  • An immune system more resistant to prion disease than your typical human, take that as you will.

  • Wiring from the nerves that affect musculature that allow both fine precision and stimulation so that they can have both strength and precision.

  • A retention of stem cell production.

  • Thicker and larger tendons than ours.

And several others that help contribute to making sure these humans don't break themselves. It should be noted however that the natural lifespan is shorter by as much as decade when compared to homo sapiens, caused most likely from the metabolic strain caused by their bodies.

In short, the question I have is what sort evolutionary path did they take on there hellhole of a world to come to this!?

The only explanation I can think of is that they had to both simultaneously fight off, and run away from, much more deadly predators while also hunting either much faster or larger and tougher prey.

Is this a reasonable explanation? Or are the characteristics described are to extreme and excessive to naturally occur?

Some additional tidbits.

  • While they are omnivores and will eat fruits and vegetables, even enjoy it, they do have a preference for meat.

  • They have larger and pointer incisors and piercing molars. Nothing to big, though noticeable when they flash a friendly smile towards you.

  • A larger nasal cavity, its only noticeable when you compare skulls as the nose does not appear any different form ours.

  • A larger ocular orbit that houses a slightly larger eye that collects more light during the evening and dawn. Again, nothing too noticeable at first glance though after inspection you could make a slight difference in size.

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    $\begingroup$ We've had a lot of questions along the lines of "Can you have a super-powered human like <description>?" with the consensus being "No". So, you're asking for how something scientifically impossible to evolve, and only giving 100,000 to 200,000 years of evolution (which is about enough to change skin colour, given strong evolutionary imperative, not fundamental capabilities). Are you accepting fantastic answers such as magic, alien superbeings with gene editing etc? $\endgroup$ Commented Jul 16, 2023 at 8:14
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    $\begingroup$ So you want a person who is a top-world bodybuilder, but is also an olympic jumper and marathoner (while surprisingly needing a lot more food -> frequent lunch pauses)... And they still need to look humans from a distance, all this in less than half a million year. I know this is a bit disappointing, but I think you need sometimes to make compromises :/. $\endgroup$ Commented Jul 16, 2023 at 9:07
  • $\begingroup$ Reminder to close-voters : explain the reason you voted to close. Here, I doubt the only upvoted comment explains specifically a "need more focus" closure :). $\endgroup$ Commented Jul 16, 2023 at 18:44
  • $\begingroup$ Hi, Seraphim. I need to start by pointing out that human limitations don't exist because someone didn't bother to figure out a way around them. It took us a while to figure out how humans could be as strong as we are. Those who haven't done the research don't appreciate this. If a creature is stronger in one area, then they're probably weaker in another to compensate. It's almost always a trade-off. That said, you're asking for eleven different improvements in a single question, so I have to suggest you ask smaller questions. $\endgroup$ Commented Jul 16, 2023 at 23:50
  • $\begingroup$ @Seraphim, if desired, please submit a new question with an edited text of this question so as to start afresh and not invalidate existing answers. $\endgroup$
    – Monty Wild
    Commented Jul 20, 2023 at 0:34

4 Answers 4


What sort evolutionary path did they take on there hellhole of a world to come to this!?

Not a hellhole. They were the apex predator.

It is a vast simplification, but we recognise two common evolutionary forms: the 'gracile' form which is thin and good at running, and the 'robust' form which is heavy and good at standing its ground. Peking Man may be an example of our 'robust' form. They are not Superman (tm). They do not toss cars. They are made of the same stuff as us; if they look like us, they probably are like us. Given a lot more than 200,000 years you might get a robust gorilla or a gracile orang-utang if evolution was left alone.

Your description reminds me a bit of the people from Harry Harrison's 'Deathworld'. If evolution played a part, you might expect them to be 'gracile' rather than 'robust'.


A few quick assumptions:

Assumption #1 Your first two paragraphs are a bit confusing. I'm assuming that what you're explaining is that sometime in the vastly distant past your hominids crossed a rift to another world and then, sometime 100k-200k years ago, they crossed back to Earth. So your question about evolution involves time "long enough to make this all happen rationally" and that time was on the other world.

Assumption #2 Asking about evolutionary paths is a tall order that usually violates Stack Exchange's book rule. Therefore, I'm assuming that what you're asking for is a short list of planetary conditions or ecological conditions that you can use to rationalize your hominids.

Assumption #3 Some of your conditions are dispensable. The problem, as mentioned in comments, is that you've created a perfect being with a list of capabilities that upon examination are a bit incompatible. Enhanced speed, for example, depends on a different kind of musculature than enhanced strength, which is why you don't see body builders winning track contests.1

Some ideas about the planet

  • Heavier gravity. This would promote both greater muscle density and leaner muscles.

  • Older world. Fewer cliffs and high mountains, more open valleys lending to lengthy running rather than jumping.

  • Mild, temperate world. There is no reason for the hominids to build significant housing, or to regularly overcome cold or rainy weather.

Some ideas about the environment or ecology

  • I completely agree with @RichardKirk about being the apex predator (and I upvoted his answer). Your hominids had to do a lot of running to chase down their prey.

  • Food is plentiful and does not require significant problem-solving skills to obtain.

  • There is a very high proportion of prey animals to predator animals, reducing competition and further reducing the need for problem-solving skills.

  • Prey is strong, but not aggressive, leading to fundamental strength being the only requirement for bringing it down, not the development of tools like spears.

You noticed how often I tried to avoid problem-solving conditions

The single biggest problem you have with rationalizing your hominids is that intelligence breeds complacence. Why do primates have a greater ratio of strength to body mass than humans? Humans stopped needing it a very long time ago. We learned how to overcome obstacles with intelligence, rather than strength. And that's a problem for your hominids. They'll be, well... if you'll forgive my bluntness... dumb as stumps. If you make them intelligent, they have no reason to rely on strength and flexibility to solve most-to-all of their problems, leading to atrophy.

Another problem: constant eating or big ol' pot bellies

You're completely right that the energy to fuel all those enhancements must come from somewhere and be stored somehow. On the alternate world, this was (perhaps) overcome with food having an unusually high energy density, thus the hominids would pass themselves off as humans — with an obvious exception. Unless they seriously scale back their physical exertions, they'll be constantly eating, urinating, and defecating. Of course, if they scale back their physical exertions, they'll begin to atrophy — and atrophy results in unusable muscles faster than you might think.

The alternative is that food on the alternate world has the same average energy density as food here on Earth. In that case, they need to store more food for longer periods of time. They'll have pot bellies due to larger stomachs, bladders, and intestines (unless you want them peeing and pooping all the time).

And then, of course, there's no intermarrying

I should think that normal humans would find your hominids desirable! Unfortunately, the influences that brought about their enhanced abilities don't exist here, so if your hominids are allowed to intermarry the result will be offspring with fewer and few of those enhancements with each passing generation. The easiest solution is to make the hominids and humans genetically incompatible so they can't breed. Another solution is to make the hominids cultural introverts with a magnificent taboo against contaminating themselves with their unfortunate cousins, the humans.

Long story short: you can't always get what you want

If you're going to stick with the science of evolution (insofar as we understand it), you must deal with the fact that evolution has compromises and consequences. Evolutionary pressure that promotes one attribute may subvert another. Characteristics left behind because they were needed in the deep past are co-opted for new purposes, go dormant, or simply disappear.

Therefore, I recommend that you grab just enough of a list of planetary and ecological influences that you can establish the basic credibility of your hominids — no more, no less — then walk away and move on with your story.

1Think about it this way. A spring that can do something quickly is light and flexible. A spring that can bear tons of weight is heavy and stiff. You can't have both. Don't get me wrong — top runners are very strong people, but every ounce of muscle has a cost to a runner, so they rarely have developed chest muscles. Boxers, on the other hand, show that heavily-built people can move quickly... but not like runners.

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    $\begingroup$ I agree with most of the contents in the answer (the only one I don't is the assumption that this alternate earth has a heavier gravity, its just 1 g though I should have been more transparent on the matter). In fact, I agree so much, that I had realized I was too unrealistic with my demands and assumptions when I was working out in the field after posting it. I came back to try and delete the question and replace it with a much more focused question since I did not put the proper thought I should. But @Richard Kirk had already written an answer so that was that. $\endgroup$
    – Seraphim
    Commented Jul 18, 2023 at 6:24
  • $\begingroup$ @Seraphim I understand completely. I personally think SE's policy of not allowing the OP to delete a question once an answer has been posted undermines their goal of quality questions. I've been stuck in the same trap where I thought I'd posted a good question only to realize later that I'd forgotten information and issues that would have improved it considerably - and can no longer delete it. Worse, an attempt to ask a better-focused version will be closed as a duplicate and this Stack has a policy of no edits that obsolete answers. It's an unproductive mess. $\endgroup$
    – JBH
    Commented Jul 18, 2023 at 15:21
  • $\begingroup$ Well there goes plan B. Would a overhaul edit work best in this situation then? $\endgroup$
    – Seraphim
    Commented Jul 19, 2023 at 1:06
  • $\begingroup$ @Seraphim if you don't mind, be patient a bit. Let me tap the moderators and find out how they'd like to handle it. Whatever the path, if you have their support, it hides the proverbial multitude of evils. $\endgroup$
    – JBH
    Commented Jul 19, 2023 at 4:12

Apologies for the second answer, but this takes a completely different tack, and is not compatible with my first answer. It also risks being judged off-topic as you original question was about evolution.

Abandon evolution as the cause of the differences. The same 'gracile' and 'robust' forms happened in warfare. Gracile horseman raiders attack your village. You build robust walls. The attackers develop siege engines, you develop thicker walls and long-term storage to resist siege. Clausewitz 'On War' (which I got at least half-way through, once) has a chapter on this. And goes on happening. The Maginot line was a robust defence. The German blitzkrieg through Holland (and round the end of the Maginot line) was the gracile attack. The tank is a robust attack weapon. The rocket or armour-piercing shell that attacks it is a gracile defence. Even nuclear proof bunkers in West Germany were mooted in the eighties as forward supplies of ammunition, tank parts, and fuel.

The robust form of war seems to grab the imagination. People like the illusion of invincibility in their medieval plate armour, or their T28 Superheavy tank. By comparison, attacking from the air or from submarine seems cowardly (perhaps by people who have never been in a submarine). But both work. If anything, the gracile form has the upper hand these days.

Suppose your people had been isolated; then won a series of battles using robust techniques. They might develop a Superman ethos, believing that the biggest, the hardest, and the strongest was always best. They take steroids, they work out at the gym, they wear heavy armour. They want to look like a Warhammer Space Marine. None of these changes are evolutionary in the DNA sense, but the result may be closer to the breeding of super-soldiers that you and others have imagined.

The usual disclaimer: you can put whatever you want in your story. If your tale is well told, you need explain because people want to believe. It is a worthy aim (IMHO) to base the story on sound research, but tales with dragons and orcs and elves still sell, or so I'm told.


Once your humanoids are human level smart, there's few selection pressures. In addition, a terrible environment selects for creatures with low calorie needs.

Humans are great at coming up with things that give them either the advantage over fast moving creatures (slingshots, spear throwers, bows) or big, strong creatures (pit traps, spears, again, ranged weapons)

There's not massive advantages to being super strong, particularly when offset against calorie requirements - if your strong humans eat 5x the food, you either need to hunt 5x more creatures, or have 5x less people in your tribe. Less people, less specialization, less technological advancement.

You've got 3 people spending their whole lives charging around after mammoths and cave bears in a desperate attempt to get enough calories, then the tribe who has 12 people, one who has been getting really into flint knapping, and the other who has had time to figure out that this thing they were using to make fire can actually shoot pointed sticks a really long way appears over the hill, who is going to win? My money would be on the flint axe and bow group, regardless of the strength of the other guys

So, this needs to happen a bit before technology really kicks off, and needs a region with a massive abundance of food to sustain these superhumans' high calorie needs. Prehaps one of the first adaptions would make them obligate carnivores, with metabolism slowing abilities when not in motion. By and large, meat is a denser energy source, and supports the kind of strength you're looking for.

Unfortunately, they're likely to be wiped out once farming comes along. Yes, they're great at fighting, but a farm can sustain far fewer of them than a regular human. And, again, one human with a bow can kill one of these super humans. So fights will go badly.

There's two paths after this: like neanderthals, they could mix heavily with humans, leaving some genes scattered around, before dying out. Or, they could be part of a sustained eradication campaign from early humans. Towns set up defenses, looking for humans with pointy teeth and big eyes. Rumors fly, spread by the large early trade networks and a new priesthood, that these creatures drink blood, that they fly in the night, and curse people. Hunting parties go out into the deep forest, searching for small groups of these humans, armed with bows, slings, and boar spears. They burn the forest, reasoning that these demons will starve without prey.

Humanity's sheer numbers overwhelm these superhumans, leaving only a few stories.


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