Hey guys, thanks for the suggestions and answers - here's a more streamlined question - presently focused on implications on climate and technology. I've also added a little more explanation in the premise.

The Premise

The Earth rotates on its own axis, which is tilted by about 23 degrees.

The setting for my fantasy novel is an earth like planet without the axial tilt, all other factors remaining constant in terms of distance from the sun etc. From some general reading on the subject, it appears the largest impact of removing an axial tilt would be on seasonal change, in the sense that there wouldn't be any changes whatsoever. Every latitudinal belt would have its own set season all year round, with some minimal changes depending on the earth's distance from the sun in its usual orbit (ranging basically from 91.4 million miles in January compared to 91.5 million miles in July - which is less than 1%).


As a result, since there is no major climate change, the world will generally experience the same weather everyday. Therefore, the cold regions of the planets are likely to become even colder to the point of being uninhabitable. Likewise for the deserts and heat. Those regions receiving lots of rainfall will either be covered in forests or experience continuous top soil erosion, making agriculture an improbable proposition in most regions.

However, it is likely that there may be a few ideal zones supporting human occupation. It may be an elevated plateau in a hot area (the altitude allowing bearable temperatures), or a large hot spring in the tundra, or an area close to other rain-heavy areas able to draw water from them.

As a clarification, the technology in this scenario is mid-Iron Age-ish (Edit clarification: pre-gunpowder).

The Question

What would be the impact on the world's basic technological aspects in various areas of the world? Some areas that I've been able to identify are:

  1. Frozen wasteland
  2. Grasslands
  3. Deserts
  4. Rocky mountainous regions
  5. Swamp lands and rainforests
  6. Archipelago

Since the weather wouldn't change, the people living in these areas would adapt differently. Real life parallels from our own planet exist even with the change in seasons. Technology in an arid desert developed differently from technology in the freeze. Technology in wet swamplands developed differently from technology in dry grasslands. If the Axial tilt is removed, these differences would grow substantially, since there would be practically no common ground for different regions with different climates. How far can these differences be extrapolated to see interesting and unique technological changes?

The answers I'm most interested in are ones which show a logical (don't worry about being scientifically perfect) impact of the premise. But if you have a ridiculous scenario arising out of the above premise, let me hear it anyway!

  • $\begingroup$ I'd suggest condensing your questions down - as it is, there are too many for one single post and this is likely to be closed as "too broad". If you could combine some of the ideas you have it would be a better post: perhaps making evolution a single point instead of two? $\endgroup$
    – ArtOfCode
    Mar 30, 2015 at 10:37
  • $\begingroup$ Also, the Goldilocks zone or circumstellar habitable zone, is different to what you seem to think. You may be thinking of a comfort zone for humans. $\endgroup$
    – ArtOfCode
    Mar 30, 2015 at 10:38
  • $\begingroup$ I meant the in-planet equivalent of a habitable goldilocks zone. Poorly put across - my apologies. Editing now. $\endgroup$ Mar 30, 2015 at 11:41
  • $\begingroup$ Welcome to the site @AmbarishSathianathan. Interesting question, but if you can break it apart it may help. I would focus on climate and its effect on plant life first for example. As it stands I feel there is too much to cover in a single answer. $\endgroup$
    – James
    Mar 30, 2015 at 13:51
  • $\begingroup$ livescience.com/18972-earth-seasons-tilt.html $\endgroup$
    – apaul
    Mar 30, 2015 at 15:58

7 Answers 7


The biggest impact on technology would be less internal diversity within a region but more diversity across the globe based on climate areas. Let's take the areas you've identified already and expand on them:

Frozen Wasteland

A harsh year-round climate would lead to little life being able to develop. Life that does develop would be very slow-growing because the cold would slow down biological processes. This would result in little to no food for people to eat or animals to hunt, so chances are people would just avoid it. Edit: This would probably cause many rumors to be spread about treasure/artifacts/monsters/etc that live there and might cause someone wealthy to mount expeditions to find it. You'd end up with some hair-brained tech developed for the purpose that could fail horribly or succeed brilliantly. Just look at our earliest theories on flying machines for inspiration on how crazy it can get before we actually understand how it works.


These would be similar to the grassy regions I described in the other question. Grass-like crops would probably bud year-round and be difficult to harvest without hand-picking or some creative method of controlled cultivation. Simple wind and animal transfer of seeds into a field could disrupt its uniformity and require constant maintenance to ensure crops are harvested with some consistency. The lack of a definite growing season would also disrupt the natural budding cycles of these plants so some might mature faster than others. Basically farming grains would be a pain, so people in these areas would likely resort to a more nomadic hunter-gatherer lifestyle, unless there's an abundance of high-value food sources like fruit and game that prevent the need to move. Large populations would be very difficult to support either way. People would also likely get very territorial due to the need for a fine balance in supply and demand. Expect long-range weaponry due to wide-opens plains giving good visibility, or if you want something more unique, make the people very adept at stealth and camouflage and the short-throw spear or miniature poisoned bow. There are tribes in Africa that use these techniques to stalk wild animals in the plains, though their lifestyle is a harsh one indeed.


Deserts not near the equator could in theory operate much as they do in the Southwestern US. Mountains could easily divert rainfall periodically to keep plant and animal populations alive, and the population would probably rely on similar cattle farming methods to what you see in our world's history. Water-storing plants like cacti would be common. Strangely enough you might see this being one of the more prosperous zones, though populations would still be small. Expect lots of water collection technology to be a necessity, and if you want to make it harsher you could make water a precious resource, though that precludes the region being prosperous. See Dune for examples of how that could shape society.

Rocky Mountainous Regions

High up the mountains would be pretty much frozen and uninhabitable. In the middle altitudes you could have large lakes, though they would have to be fueled entirely by rainfall since you won't have spring melts of snow caps. I'd expect much of the population to center around the lakes and their distribution systems, and the people would live primarily off of hunting and whatever high-value fruit/vegetables can grow in the rocks. Expect small populations but relatively stable places to live since they have a good supply of water, which perpetuates more lush plant and animal life. Think of a "mountain oasis". I'd expect those people to be pretty reverent towards their water source as the giver of life. You might see an abundance of mining technology just out of necessity to build habitats, though if the mountain is very geologically active that could be a risk. If not, they could take advantage of the increase in temperature you get as depth increases, though be careful to avoid asphyxiation.

Swamplands and Rainforests

These would probably be your centers of civilization. The abundance of water and warm temperatures would mean an abundance of wildlife. People here would have wood to make tools and shelters, a huge variety of food to eat, possible easy travel down rivers, etc. Houses would likely be elevated somewhat to deal with flooding or in the case of the swamp they may just be permanently floating. You'd possibly have some sort of agriculture in the swamp regions, though it wouldn't be grains, perhaps edible reeds or other water-borne vegetables. In the rainforests you could also have good mining locations for metals and stone. A large enough population could clear out an entire swath of land to build an empire, though they would have to be mindful of the ground they build it on. Stone buildings would be useful, and wood structures would need to be treated with some sort of tar-like substance to prevent rot. These would also consequently be dangerous places to live, with the abundance of wildlife meaning there are just more things out there to kill you in strange ways, necessitating many precautionary measures and weapons/tools that would border on being ritualistic after several generations. Get creative!


Another potential for lush wildlife but only if they're in a warm enough climate to have lots of rainfall. Either that or your oceans would need to be freshwater and I'm not sure what the implications of that are. These places would probably be much as you see them on Earth, with tribal villages being the norm and relative isolation from the rest of the world until someone invades. You could build them up to be a culture clash after that happens, just think about occupation-era Japan for inspiration on how two cultures can combine in a totally unique way (not to mention the social stresses it would cause). Expect tools to be somewhat sophisticated but shelters to be impermanent due to the likelihood of being destroyed in a storm and needing to be rebuilt easily. I think it would be fun to have a culture that reveres the cycle of death and rebirth in these situations, as exemplified by the potential for weather to wreck everything, forcing them to rebuild from scratch. You could expand that into their whole style of technology, perhaps their tools are all one-use and disposable despite them knowing how to make better ones, they just choose to let things break as a sign of acceptance that they themselves may be broken on any given day that nature determines. Outsiders would view them as incredibly primitive when in fact they're incredibly intelligent and sophisticated, they just show it differently.

Other Interesting Bits

You can get creative with some areas like the hot spring you mentioned. People would probably have to have migrated there at some point, rather than it being a place of origination. The hot spring in a frozen tundra would support a unique kind of plant and animal life that could be very different from everywhere else, but the limiting factor is the size of the spring. The smaller it is, the less life it can support. If you make it a larger system of springs connected by short distances of streams (such that they wouldn't freeze over in transit from one spring to the next) you could extend it a bit, but remember this is going to basically be on a fault line so there will probably be mountains and other geological features surrounding it.

Just keep in mind that mountains are great at diverting rainfall, so you can bring water to places it wouldn't normally be, and since there would be a reduced ability to transfer water through natural means like seasonal melts, irrigation will be key to any developing area that doesn't have lots of water already. There could be an empire in the grasslands, but only if they have the water and trade supplies to support it. It would be much easier to build that empire in a wetter climate.

Also take advantage of massive rivers like the Nile or Amazon that connect two large bodies of water. The Nile in particular made life possible in Egypt, and that river alone allowed them to build an impressive empire despite the harsh environment, especially with the advent of river shipping techniques. A more advanced society with slightly different terrain might take advantage of the water to power massive mining operations or other large industry. As happened in history, these people would likely view the river as the source of life and it would feature prominently in their religion and tradition.

Wherever people live, providing shade would probably be an important feature of their technology. The lack of seasons would make constant sunlight harmful in many areas not near the poles. Consider large-brimmed hats, parasols, covered carts and full cloaks/robes as well as shaded places to rest an important feature between the grasslands and the equator. Good ventilation in any warmer area is also a necessity. Also make sure your distribution of skin pigmentation reflects the climate, assuming your people are biologically tuned like us.

Hopefully that covers it. If I missed something let me know.

  • 3
    $\begingroup$ Neat answer. Note on swamplands and marshes. These areas are quite fertile and in both Egypt and Mesopotamia presumably supported civilization very early. (But left few permanent structures for us to find.) In addition to being rich in wildlife (fish, birds, etc) very productive agriculture is possible using solutions similar to Mexican chinanpas. The Americas also had highly productive low tech solutions for tropical forest and mountain area agriculture. In many areas Europeans significantly reduced level of agricultural productivity... $\endgroup$ Apr 25, 2015 at 12:59

Actually there would still be seasons unless the orbit of the planet was also exactly circular, which is possible but unlikely. Also the axial tilt varies over time. Earth is unusually stable because we have a large moon. I guess that if you are asking about effects on evolution, the planet also has a large moon to stabilize the axial tilt?

The rain cycle

This would make seasonal rain patterns such as monsoons much less likely. The result should be areas distant from oceans being more arid and less likely to support agriculture. There would probably still be oscillations in rain patterns and climate, but they would be either weaker or less predictable and longer lasting. So that people that moved into areas made fertile by the rains, would have to move out or die when the rains do not come.

Otherwise the difference would not be that big I think. Most rains come from ocean evaporation and start coming down as rain when already over the ocean, and seasons simply move the climate bands north and south. These seasonal movements would be removed, but weather itself should otherwise be the same.

Plants and animals

No seasons would mean that there would be no need to adapt to seasonal variations in temperature or rain fall. Droughts and floods would still happen so adaptation to unpredictable weather would still be needed. I'd expect plants would be evergreen since a place that they can grow would presumably be so all the time. Animals would not do large seasonal migrations or hibernations and other such seasonal adaptations. Estivation might still exist as drought adaptation. Plants would presumably regrow from roots or seeds.

Otherwise the effects should be relatively minor as most of biological diversity and biomass is in stable environments that allow growth year around anyway.


There would still be weather and for most of history almost all people lived in warm climates anyway. Only difference would be that there would be no real sense making buildings snow and freezing cold proof as areas with such weather would have such weather year around, there would be no summer growing season producing the food to support human population. Still weather might bring snow to far south occasionally, so lack of seasons would not really allow people to skip on protection.

Architecture would be subtly different in that in many civilizations roofs were designed to create shade during summer but let sunlight warm the house during winter.


Population would be concentrated the same way it was on Earth in a belt of areas where the temperature is above freezing, no real winter, year around. Not having seasons might extend this belt slightly, but I doubt the difference would be significant, the border just would be less fuzzy with areas outside this belt being not really habitable at all without summer growing seasons.

Population distribution within this zone and actual climate would depend on geography, mainly the distribution of land and sea.

Navigation and Exploration

Not sure there would be much of a difference. Determining latitude would be easier, but that was never really much of a problem. Determining longitude would also be slightly easier without leght of day varying, but enough issues would remain to require essentially same solutions as on Earth. And longitude problem was historically solved after the age of exploration, so it didn't really prevent exploration anyway.

  • $\begingroup$ Actually there would still be seasons unless the orbit of the planet was also exactly circular, which is possible but unlikely. The variation in Earth-Sun distance has a negligible direct effect on climate — the only effect is secondary through its effect on length of the seasons. $\endgroup$
    – gerrit
    Apr 7, 2015 at 17:33
  • 2
    $\begingroup$ @gerrit Yes, I know, I live on the planet Earth, actually. The effects of distance are swamped by the effects of the axial tilt. But this is a planet without axial tilt, so the effects of the eccentricity of orbit should be much easier to detect, if the orbit is eccentric at all. It might conceivably be the largest source of annual variations, or seasons. Obviously the seasons would be nothing like the ones on Earth unless the eccentricity is of the correct size, which is why I ignored them in the rest of the answer. Just included that note for completeness, really. $\endgroup$ Apr 10, 2015 at 9:31
  • $\begingroup$ With the size of the direct effect on Earth it would still be swamped by weather. $\endgroup$
    – gerrit
    Apr 10, 2015 at 14:29
  • $\begingroup$ @gerrit Yes, again obvious (unless of course eccentricity is extreme, but that would be another question). But weather != seasons, so it isn't really relevant how much larger the normal weather variations would be compared to seasonal changes due to eccentricity. Seasonal variations would still be under the weather and noticeable since most weather patterns are faster than seasonal cycles. Probably wouldn't be large enough to have much practical consequence, but I only wanted to point out that they would still exist, and they would. And things like monsoons might locally make it larger. $\endgroup$ Apr 10, 2015 at 23:38

It might be helpful to have a discussion about whether intelligent life would evolve at all on a tilt-free planet, before discussing differences in the technology that intelligent life might devise. Loss of Planetary Tilt Could Doom Alien Life, Axis Tilt is Critical for Life


I always had the impression that the seasons, and the necessity to cope with them on the one hand, and the large amounts of boredom in winter on the other, might have led to a lot of innovation.
As a result i think that a lack of seasons would massively slow down innovations of all kinds. While you will likely go as far as pottery in a timeframe comparable to the one that happened on this earth, i doubt that you would get much beyond simpler metallurgy any time soon.
The reason, in detail, is, that first of all innovations need someone with time to think and tinker, and secondly, you need some sort of outside pressure for humans (in general as well as in detail) to move anywhere.
If, as @VilleNiemi suggests, all of humanity lived very much in the same geographical belt, they would neither have winters that provided the free time, nor the pressure to avoid freezing and starving.
While, over a sufficiently large timespan, it would still be possible to evolve to and beyond our current state, i guess it would take a lot longer.
To back up my view i would like to point out that most of the greater inventions (good and bad) of the last two millenia have been made in regions with notable to strong seasons while the populations in regions of moderate climates pretty much stagnated in or after the iron age. And that is even though those regions had kingdoms and the like, that would provide a part of the population with time and ressources, and (a different) part of the people with pressure to improve their situation.

  • $\begingroup$ populations in regions of moderate climates pretty much stagnated in or after the iron. What? Western Europe stagnated? The population in areas with moderate climates have been far more successful than populations in more seasonal climates, to the point of conquering almost the entire world. $\endgroup$
    – gerrit
    Apr 7, 2015 at 17:36
  • $\begingroup$ I never said western europe stagnated. Le last massive conquerers from the moderate climates would have been the romans. They fell victim to the huns and turks if i am not mistaken. And after that the regions with more pronounced seasons became stronger and stronger, while in the warmer climates you found mostly stagnation. Look at Arabia, Egypt, Mesopotamia for example. I may have the term 'iron age' wrong, but i gather my general statement should still hold? $\endgroup$
    – Burki
    Apr 8, 2015 at 7:12
  • $\begingroup$ But the countries that more or less conquered all of the Americas, Africa, and parts of Asia, are France and the UK. Both have very moderate climates. By comparison, North America has a continental climate, South America and Africa are hot. Asia has both hot parts and strongly continental parts, but the most successful Asian countries in the 20th century were South Korea and Japan, which again have maritime climates with less pronounced seasons that China or Mongolia. The only exception I can think of is when Mongolia conquered Asia, but otherwise, moderate appears a bonus, not a malus. $\endgroup$
    – gerrit
    Apr 8, 2015 at 14:31
  • $\begingroup$ You may have a point, @gerrit. I will think about it. In the mean time i would like to point out that, as far as i know, japan only started advancing (again) after coming in contact with foreign countries (and tried to minimize that effect for a very long time). That let aside, i definitely have to give my impressions a workover, since they do work for arabia et al, but not, say, for spain. $\endgroup$
    – Burki
    Apr 8, 2015 at 14:56

Transmission of Technology

For much of human history, climate and geography have been significant barriers to human travel, which slows technology transfer (and by technology I don't necessarily mean things like swords - I also mean domesticated animals or crops, or concepts like "wheels" and "pointy sticks").

Since your world has no axial tilt, technology and knowledge will travel faster to new areas, at least on an east-west axis (and taking geographical climate changes into account). You don't have to worry about seasonal restrictions on travel, or climate changes that will kill or stop crop spread. So I suspect this would cause early technological development to happen much quicker than on Earth. Even south-north travel would likely be simplified because it would be more constant, rather than changing.


Climate can be a significant defensive barrier. It's likely that on your world, an army used to one climate might have trouble adjusting to another. This would tend to limit short-term military expansion across different latitudes - military civilizations would tend to conquer and spread laterally in bands, east-west, but would have much more trouble spreading south-north. It would also make mountains more significant barriers - soldiers who have never seen snow are going to have a lot more trouble with a mountain pass, compared to soldiers who see it several months a year.

Natural Disasters

Consider that on Earth, most people live in areas with seasons. That means if something big, natural and bad happens - like the Year Without a Summer - it causes hardship, but it's not totally outside of their experience so people can adjust. They know how to handle winter, so they can prepare and try and set things up to survive a longer, colder winter. It still kills a lot of people, but in general populations survive and recover.

But what happens in your world, without an axial tilt? Instead of just being a hardship, suddenly they're inflicted with a temporary weather and climate that they have no experience or preparation for. It's likely that if a natural disaster occurred on that level that anyone living in marginal areas is simply dead - they have no preparation for that kind of event at all. So your world might experience periodic (~1 thousand years) die offs of humans who live in marginal areas, followed by slow re-population as the people in ideal areas spread out.

Alternatively, a civilization with a strong oral tradition that "remembers" how to handle winter might survive and spread, taking over the marginal areas because they're the only ones who can handle a winter every thousand years.

This would also cause an interesting effect on evolution, because species might adapt to an area and then be killed off in mass. But I think that's probably beyond the specific scope of this question.


I would expect such a planet to be a dull vegetated place. With no seasons, microbes would adapt to very particular temperature ranges of their latitude, and have disincentive to migrate. Being a little jellyfish and going around gobbling up the plankton might be ok but there would be far less reason than on earth to become a good swimmer for migration, let alone grow legs and run around doing cleverer stuff than what jellyfish do.


I disagree on the lack of diverse speciation because of far less variant seasonal biomes. If you look at places like the Canary Islands (i.e. isolated ecosystems at an equatorial latitude with minimal seasonal variance) you find similar levels of diversity and speciation as you would in a latitude with well-differentiated seasons.

Once the first photosynthetic mega-bloom freed enough oxygen to make cellular combustion selectively efficient I can't imagine how ANY climate which allowed for liquid water could possibly stop the rise of animal life. The first proto-mitochondria awoke into a Willy Wonka-esque picnic where their brats created themselves from piles of poo and, as a by-product, filled all the park's grills with charcoal briquettes.

Plants aren't sessile because they don't NEED to move, they simply can't produce enough free energy quickly enough to ever make movement selective in an oxygen-rich environment. Likewise animals aren't mobile because there were storms and snow, they're mobile because it's thermodynamically possible for them to be so and movement is incredibly selective in any environment.

At least, that's how I see it -- hope it's helpful to you three years ago :P

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    Sep 27, 2017 at 7:26

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