Pangaea
Contents:
Pangaea is an extension of/response to Phanerozoon.
My objective is to take the basic format of the original, but to start
from a unicellular LUCA,
with multicellular life evolving only gradually, and also to encompass
the whole tree of life, i.e., not just mostly eukaryotic, mobile
heterotrophs, but sessile autotrophes like plants, sessile heterotrophs
like fungi, diverse offshoot clades like protists, and hypothetical
clades filling niches that are rare or absent in our world, like mobile,
multicellular autotrophs. I also want to add a geographic and geological
dimension.
There is a tension between simplicity and elegance and granular
simulation, and while I generally prefer the former over the latter, I
am still trying to find the right balance between the two. This page is
very much a work in progress.
How to play
The game has no GM, and is played remotely. Initial setup requires a
blank world map and a suitable place for recording player actions, like
a Discord server or forum thread. You will also need a flexible random
number generation method. The game is divided into rounds. Each round
lasts 24 hours. At the beginning of a round, one player rolls a dice (or
generates a random number) to choose a random event from the Random
events table. Players then follow the instructions for that random
event. During a round, players may take up to three actions to evolve
new species--really families of species or entire clades--or to alter
the geology of the world. A player may take a fourth action if they also
draw a picture of a species that hasn't been illustrated yet. Each round
represents roughly ten million years of geological time (maybe more in
the early game before multicellular life evolves).
At the start of the game, the world map is blank, the global average
temperature is 15 degrees C, the atmosphere is devoid of oxygen, and the
only species available to evolve is the LUCA of all future life on this
world, a single-celled microorganism with the adaptations extremophile
(thermophile), autotroph (chemoautotroph), and anaerobe.
It is sometime in the murky middle of the local Proterozoic eon, long
after the beginning of life, but long before the first multicellular
organisms that will leave fossil traces. On the first round, instead of
a random event, the world properties are chosen as laid out here.
If you are playing as part of a larger campaign, continue play until at
least one approximately human creature has evolved. You may wish to
shorten the nominal turn length to anywhere from 1 million to 100,000
years after you reach Ad-hoc tool use. Otherwise, play can
continue indefinitely, or mounting geological catastrophes render your
planet uninhabitable.
Player actions
Player actions can alter existing species ("evolution actions"), or
alter the physical world ("geology actions"). Unless otherwise noted,
you can do any action any number of times per turn. This includes:
- Create a new species by applying an adaptation to it. Choose an
adaptation from the list of available adaptations (either one which
seems interesting to you, or at random), and choose a species that
evolved on a previous round to apply it to. This creates a
daughter-species branching off the main species, which continues to
exist. You may remove an adaptation instead (if it is removable), or
apply an adaptation and remove an adaptation as part of a single
action. You can't modify a species that only came into existence this
round, but you can evolve multiple daughter species from a single
parent in the same round.
- You can add two or more adaptations to a single species, with the
same restrictions as above, but any adaptations beyond the first can
only be a basic adaptation (found in the Basic
unicellular adaptations table for unicellular species, and the Basic multicellular adaptations for
multicellular species). This counts as multiple actions--two, if you
are adding two adaptations, three action if you are adding three
adaptations, and so forth.
- Target a species for extinction. Roll a 1d6; on a 1-5, the species
is extinct. On a 6, the species goes extinct, but an offshoot survives
with a new random trait chosen from among available basic adaptations.
You can't target a species for extinction in the same round that it
evolved. Also, extinctions only take effect at the end of a
round: you can always evolve a species if it was alive at the
beginning of a round, even if a random event or a player action
renders it extinct later in that round.
- Resurrect a Lazarus
taxon. A species that was thought extinct before has
actually survived, or perhaps been resurrected by some kind of
spacetime anomaly or alien intervention. If this species went extinct
one or two rounds earlier, this counts as a normal action. If this
species went extinct three rounds ago, this counts as two full
actions. If this species went extinct four rounds ago, this counts as
three full actions. If this species went extinct five or more rounds
ago, this counts as four full actions, and thus you can't take this
action unless you draw a picture for an extra action point. No matter
what, you cannot take this action more than once per round.
- Alter geology. You can fill in a blank area on the map that's
up to 2,000 px square with any terrain you like; or, if it's an area
that has already been filled in, you can raise or lower the terrain in
that area a single level. You can't alter an area another player has
already altered this round. For more detailed explanations of how this
works, see Altering geology.
- Special geology action. You can take a special geology action, which
has a more focused and often greater effect. Choose a special geology
action from the Special geology actions
table. As with altering geology, you can't use special geology actions
on an area another player has already altered this round.
Once you take an action, describe how it happened with a sentence or
two. Justifying actions narratively and giving them context in the world
is the core of gameplay.
In a Discord server or other context that allows it, you may want to
format evolution actions as individual replies to earlier messages about
that species, in order to make it easier to keep track of their history.
When applying an adaptation, you should include the name of the new
species, the name of the parent species, what adaptation(s) it is
gaining or losing, and a short description of how the adaptation
occurred and/or the new appearance/behavior of the species. I recommend
the following format:
- Trilobite (+reduplicated body part
(abdominal segments)) <- Parvancorina
One population of Parvancorina develops an extended
segmented body, with individual armor plates and a distinct
three-lobed structure. The result is the trilobite, which
lives on the floor of warm, shallow seas.
For geology actions, you should copy-paste your alterations into a
full-sized image of the world map, so other players can use it as a base
without having to merge different versions of the map (see Altering
geology, below).
Trilobites were a diverse class of arthropods that
thrived in the lower Paleozoic. "Species" in Pangaea represent whole
families of closely related organisms like this, though how diverse they
are exactly is up to your imagination (and your art skills). Not that
your illustrations need to be as high-quality as this one!
Applying adaptations
Adaptations are grouped into categories, and within each category, some
restrictions may apply. For example, as you might expect, unicellular
adaptations only apply to unicellular species, while multicellular
adaptations only apply to multicellular creatures. Some
adaptations are mutually exclusive: a creature is usually either a heterotroph
or an autotroph.
Many adaptations have prerequisites. For example, the taproot
adaptation requires the root system adaptation. If a species
has both, you cannot remove the prerequisite adaptation while evolving a
new species, unless you also remove the adaptation that depends on it.
During an ordinary evolution action, you can always remove one
additional adaption to create a new species, but only if that adaptation
is a prerequisite to an adaptation you are also removing that turn, and
no other adaptations the species has also have that adaptation as a
prerequisite. For instance, you could remove both flowers
and seeds from a species that has only those two adaptations;
but you could not remove seeds if the species also had the
adaptation fruit, which depends on seeds also.
Some other adaptations are irreversible. These
adaptations usually reflect major changes in body plan that become
inextricable parts of a species' overall form or metabolism. An example
of this would be bilateral symmetry. Having evolved a
fundamentally bilateral body plan, few or no animals have ever
subsequently dispensed with it. Animals that have evolved, e.g., radial
symmetry, like the starfish, have done so as a special case within the
broader category of bilaterians; and other asymmetric animals, like the
flounder with its migrating eye, are bilaterians with some incidentally
asymmetric adaptations based on a bilaterian body plan. Irreversible
adaptations are noted as such in the tables of adaptations.
When the game calls for a random adaptation, use a random number
generator to choose an adaptation from the Basic adaptations table.
These adaptations represent more genetically superficial, niche-filling
adaptations, and are never irreversible, nor do they act as
prerequisites for other adaptations.
Optional rule: Fixed
extinction rate
If you have a convenient way of storing the list of living species like
a spreadsheet, you can remove the ability to do targeted extinction
actions as normal, and instead implement a fixed extinction rate rule:
for every species extant at the start of a round, roll 1d20:
on a 1-5, the species goes extinct (but can still be resurrected as a
Lazarus taxon); on a 6-20, nothing happens. This rule should keep the
number of species manageable, while allowing players to focus on other
actions like evolving new species and altering the geology.
Altering geology
The world starts as a blank image, 1000 pixels wide and 500 pixels
tall. We use a Hammer
projection since it is equal-area; this means there do not have to
be complicated rules to adjust for how much land geology actions are
permitted to alter near the poles. The Hammer projection is also
accepted as an input in G.Projector,
a tool that can re-project the map into other projections, or change the
central meridian. Altering the projection can be useful to avoid common
traps of fictional map-making, where cartographers often unwittingly use
the shape of the drawing surface to guide the shape of their
coastlines--producing squared off continents to fit squared off paper,
for instance. At 1000 px by 500 px, the 15-degree graticules in the
image below are about 1700 km apart at the equator, assuming an
Earthlike world. This corresponds to about 45 pixels.
![Blank Hammer projection A Hammer projection showing only lines of latitude and longitude without landforms or other features.](hammer.png)
For gameplay purposes, only certain physical features matter. Rivers, for
instance, though they can be presumed to exist anywhere on the planet with
ample rainfall, evolve over timescales that are often very short compared
to the many millions of years in a single round; seasonal and and
transient events are also not going to have a long-term effect on the
world, unless they are cataclysmic in scale. Thus, the principle features
you should track on your map (and which you can alter with geology
actions), are approximate
elevation, important tectonic features
like
fault lines and
hotspots, major
orogeny, and
ice sheets.
![Map example An example of major terrain features and how to mark them.](map_example.png)
The image above shows one way you can mark terrain
features. There are five elevations that must be tracked:
deep ocean,
i.e.,
dense
basaltic crust without an overlying continental landmass;
shallow
ocean, i.e.,
continental
shelf, granitic continental crust which is relatively low-lying and
has been flooded either due to subsidence or a rise in sea levels;
low-lying
land, which represents any kind of plains, coastal plain, or even
rough terrain which is not high enough to alter the local climate;
upland,
like plateaus and low-lying mountains; and
mountains, in this case
representing specifically young and very elevated mountain ranges, or
extended regions at a very high elevation. In a normal geology action,
terrain can only be raised or lowered a single level: from deep ocean to
shallow ocean, from shallow ocean to low-lying land, from low-lying land
to upland, or from upland to mountain; or any of these in reverse. These
elevation changes can represent many different kinds of geological
activity: subsidence or uplift due to volcanic activity, the rebound of
land after the melting of an ice sheet, erosion, a local spell of
volcanism due to a minor hotspot or a nearby convergent plate boundary,
the raising or lowering of sea levels, or the deposition of sediment by
water or wind. For ice sheets, the underlying terrain is instead shown in
grayscale.
Fault
lines, whether they represent convergent or divergent plate
boundaries or some other kind of discontinuity, are marked in dark red
lines. Any area of the map completely enclosed in fault lines is its own
tectonic
plate.
Special geology actions
The following actions are available as special geology actions.
Action |
Effect |
Create/remove fault |
Add or remove fault lines that are in total no more than 50
pixels in length. Subsequent motion of tectonic plates will
determine exactly what kind of fault this is. |
Continental drift |
Shift a tectonic plate by up to 30 px. As part of a continental
drift action, you can specify how landforms evolve along the
margin of the tectonic plates affected, up to 50 px on either side
of the fault line. |
Create/destroy major hotspot |
Create a major hotspot beneath the oceanic crust. Speckle the
plate with islands as it moves over that hotspot during future
rounds, or create a single large island if the plate is stationary
for several rounds. |
Orogeny |
Add mountains up to maximum elevation,
anywhere on a continent that's being pushed into a convergent
boundary, in a region up to 3,000 px square. Weak spots in the
crust can cause buckling and flexing even well away from fault
lines, with brittle crust, at geological scales, as much like
fabric as like rock. |
Flood
basalt |
A major episode of volcanism floods a region. You can raise the
terrain in a region up to 4,000 pixels square; the global
temperature increases by 1 C. |
Bolide impact |
A large asteroid impacts the planet; mark an impact crater up to
5 px in diameter. If it hits land, dust from the impact and from
massive fires decreases the global temperature by 1 C. |
Outburst
flood |
Scour out channels from the margin of an ice sheet to the
nearest sea, up to 100 px in width. |
Continental drift
Plates generally drift in roughly the same direction for many millions
of years, driven by convection currents in the mantle of a tectonically
active world. This motion is not smooth and continuous however, and has
a great deal of variation.
Where oceanic plates meet oceanic plates, one will subduct beneath the
other, creating an upwelling of volcanism at the plate boundary, and,
frequently, island arcs and archipelagos like Japan and the Philippines.
Where an oceanic plate meets a continental plate, it will subduct, as in
the Pacific Northwest of America, creating similar volcanism in the
continental landmass, and with islands and small landmasses embedded in
the oceanic plate frequently collecting on the margin of the continent.
Where two continents meet, as at the Himalayas, the result is usually a
large region of mountain-building.
Where two plates recede from one another, the result in the ocean is a
mid-oceanic rift, like the Atlantic ridge, and rift valleys in
continents as in East Africa.
None of this behavior must be imitated in the history of your
own world. These are guidelines and advice to facilitate creativity, not
hard and fast rules.
Global temperature and ice
sheets
The average global temperature starts at 15° C. For each degree below
15° C, polar ice sheets will cover land to about six additional degrees
of latitude--so while at 15° C there are no polar ice sheets, at 14° C,
ice sheets extend from the poles to 94° N and 94° S; at 13° C, they will
extend to about 88° N and S; and so on. When the average global
temperature reaches 0° C, all land may be covered in ice sheets, though
the seas may still be warm enough to support ice, and the equatorial
oceans in particular are likely to be ice-free. At -5° C, the whole
world is covered by ice at least part of the year; at -10° C, the ice is
too thick to support photosynthetic life, and all
photosynthetic life will
die, in addition to every species that relies on photosynthetic life as
part of its food chain. If somehow your plant gets to -20° C, life on
your world has gone extinct, and the game ends.
Similarly, if the global temperature is higher than 40° C, the climate
will become unstable; at the end of each round, the temperature of the
planet will increase by 1° C. If the global temperature rises higher
than 50° C, it will increase by 2° C, and above 60° by 4° C.
Additionally, if the global temperature is higher than 60°C at the start
of a round, you must roll a mass extinction event:
roll 1d6 for every species. On a 1-3, they go extinct.
On a 4, they survive unscathed. On a 5, the original goes extinct, but a
surviving offshoot gains a random adaptation. On a 6, two surviving
offshoots are created instead of just one. If the global temperature
reaches 70° C, life on your world goes extinct, and the game ends.
Oxygen Catastrophe
At the beginning of the game, the atmosphere of your world is anoxic
and weakly reducing; most life is some form of chemosynthetic autotroph,
and any oxygen that does get added to the environment quickly reacts
with iron or other elements and is sequestered. For each species with
the autotrophy (photosynthetic) adaptation at the end of a
round, the Oxygen Catastrophe counter increases by 1. When it reaches
100, the Great Oxidation event occurs instead of a random
event at the start of the next round. Each player may choose one
anaerobic species with one extremophile adaptation to
preserve. All other anaerobic clades are wiped out as
the atmosphere shifts to one that is toxic to them.
Biomes
TBD
Tables
World properties
When creating a new world, choose a random gravity between 10% Earth's
gravity and 150% Earth's gravity; choose a day length duration from 6
hours to 200 hours; choose a random axial tilt between 90 and 0 degrees;
and choose a random number of large moons (moons large enough to be
rounded by gravity) between 0 and 3.
Primary body
The primary body the world orbits is:
- An M-class star
- A G-class star
- A K-class star
- An M-G binary
- A G-K binary
- A gas giant.
If you rolled "gas giant," re-roll for the giant's primary, treating a
6 as "roll again." "Axial tilt" becomes the gas giant's axial tilt, and
your world orbits it around its equatorial plane. Any large moons your
world has become sister moons of your gas giant parent.
If your primary body is an M-class star, triple the length of your day
due to tidal forces. If the result is over 100 hours, your planet is
tidally locked to its star. If your primary is a K-class star and the
length of your planet's day is greater than 150 hours, your planet is
also tidally locked to its star. If your primary is a G-class star, and
your planet's day is greater than 190 hours, your planet is tidally
locked to its star.
Random events
Roll |
Event |
1-3 |
Global cooling - The global average
temperature decreases by 1d4, due to environmental feedback loops,
an increase in albedo, a decrease in solar output, or some other
factor. |
4-6 |
Global warming - The global average
temperature increases by 1d4, due to environmental feedback loops,
volcanic outgassing, an increase in solar output, or some other
factor. |
7-9 |
Climate stabilizes - If the global average
temperature is greater than 15 degrees, decrease it by 1d4
degrees. If the global average temperature is less than 15
degrees, increase it by 1d4 degrees. If decreasing the global
temperature would lower it below 15 degrees, or raise it above 15
degrees, it remains at 15 degrees instead. |
10 |
Massive bolide impact
- An enormous asteroid strikes the planet, causing a mass
extinction event. Roll 1d6 for every
species. On a 1-3, they go extinct. On a 4, they survive
unscathed. On a 5, the original goes extinct, but a surviving
offshoot gains a random adaptation. On a 6, two surviving
offshoots are created instead of just one. Due to geological
aftershocks, Alter geology actions can alter up to 3,000
px square this round. |
11 |
Supervolcano eruption - Choose a
sub-continental hotspot (or, if none exists, create one). This
hotspot triggers a massive, explosive eruption that fills the
upper atmosphere with soot, and decreases global temperatures by 2
C. Every player gets an additional, free Targeted extinction
action this round. |
12 |
Evolutionary explosion - Due to environmental
factors not visible in the fossil record, meddling by traveling
hyper-advanced aliens, or some other unknown factor, this era is
an especially fruitful one for biological innovation. Every player
gets an additional, free Apply adaptation action, and
you may target species that were evolved in this round. |
13 |
Rare adaptation - An incredibly rare or
improbable trait evolves in one species. Apply a random trait from
the Rare trait table to a species of your choosing. |
14 |
Large igneous province forms - Choose a
divergent plate boundary or hotspot, or, if no suitable location
exists, create a hotspot. For the next 1d4 rounds, global
temperature increases by 2 C per round. While the large igneous
province is forming, alter geology actions can alter up
to 3,000 px square. If the large igneous province takes more than
two roudns to form, then on the third round, a mass
extinction event occurs: roll 1d6 for every
species. On a 1-3, they go extinct. On a 4, they survive
unscathed. On a 5, the original goes extinct, but a surviving
offshoot gains a random adaptation. On a 6, two surviving
offshoots are created instead of just one. |
15 |
Panspermia - An asteroid carrying an extremely
hardy extraterrestrial lifeform crashes into the planet; against
all odds, it has survived both travel through space for an unknown
length of time, and the impact. A single-celled organism with the
adaptations autotrophic, radiophilic, psychrophilic,
endospore-forming, facultative anaerobe, and two
other random adaptations appears. This event can only
occur once. If rolled again, re-roll. |
16 |
Alien visitation - Alien explorers visit the
planet for inscrutable reasons. Roll a 1d6 to determine which of
the following activities they undertake:
- Leave behind mysterious scattered artifacts (each player
describes one artifact or type of artifact and its function or
purpose)
- Leave behind an immense megastructure (next player describes
its function or purpose)
- Wage some kind of war with one another (next player
describes its aftermath)
- Conduct biological experiments (each player gets one free Apply
adaptation action)
- Conduct geological experiments (each player gets one free Alter
geology action)
- Conduct climate experiments (global temperature regresses
1d4 toward 15 degrees)
|
17 |
Bizarre geology - Some incredibly improbable
confluence of factors (or possibly outside intervention) has led
to a bizarre geological formation on your world. Roll a 1d6 to
determine what kind:
- Vast underground caverns and seas
- Regions of enormous crystalline growth
- A massive, Valles Marineris-style canyon (each player
contributes up to 2,000 px square to its shape)
- A single enormous mountain
- Some kind of floating or flying landmass
- Make something up!
|
18 |
Bizarre skies - Some incredibly improbable
confluence of factors (or possibly outside intervention) has led
to a bizarre meteorological or celestial phenomenon on your world.
Roll a 1d6 to determine what kind:
- A permanent superstorm
- Planetary ring
- Acquisition of a small asteroid moon
- Aliens leave megastructure, ship, or space station in orbit
(next player describes its function or purpose)
- Cloud-like formations made of something other than water
vapor and ice
- Make something up!
|
19 |
Make something up, or pick any outcome off this table. |
20 |
Roll twice on this table. |
Adaptations
If an adaptation has variations listed, a variation must be chosen
when the adaptation is chosen (multiple variations can co-exist). If an
adaptation lists variations including "something else," those are merely
suggestions to get you started. Adaptations marked with an asterisk are
irreversible. Adaptations marked with a + sign stack.
Note that a few traits are automatically present by simple exclusion;
any species doesn't have sexual reproduction has asexual
reproduction by default; any species that doesn't have autotroph
automatically has heterotroph; and any species without some
kind of aerobic adaptation is automatically an anaerobe.
If you want to explore niches that remain unfilled in terrestrial
biology, might I suggest this
paper on so-called 'forbidden phenotypes'?
Basic unicellular
adaptations
Use this list of adaptations to choose a random adaptation.
- Biofilm
- Bioluminesence
- Cell-to-cell signaling
- Cell wall
- Conjugation
- Crystalline deposits
- Electrosensitivity
- Endomembranes
- Endospores
- Extremophile (has variations thermophile, halophile,
acidophile, psychrophile, zerophile, alkaliphile)
- Eyespots
- Flagella/cillia
- Magnetosensitivity
- Meiosis
- Phagocytosis
- Pseudopods
- Symbiosis (has variations mutualism, commensalism, parasitism)
- Syngamy (requires meiosis or conjugation)
- Stromatolites (requires biofilm)
- Taxis (e.g., chemotaxis, phototaxis, magnetotaxis, thermotaxis,
barotaxis, gravitaxis, or something else).
- Toxin production
- Trichocysts
- Unusual shape (e.g., rod, pillow, corkscrew, lozenge, cube,
flat, lumpy, or something else)
Advanced unicellular
adaptations
- Autotroph (fixes carbon as part of energy production; has variations
chemoautotroph (requires volcanic activity), lithotroph,
electrotroph, phototroph (requires sunlight), diazotroph.
Autotroph always replaces heterotroph. A species can
only have one kind of autotroph)
- Heterotroph (cannot fix carbon, replaces autotroph)
- Alternate reproduction (has variations budding, fragmentation)
- Aerobe (replaces anaerobe, has variations aerotolerant
(can survive in an aerobic environment), facultative aerobe
(has both aerobic and anaerobic ways of producing energy) and obligate
aerobe (cannot survive without oxygen). A species can have
only one kind of aerobe. Requires the Oxygen Catastrophe
counter to be at least 20.)
- Endosymbiosis (allows clades diverging from this one to take an
additional kind of autotroph adaptation, or heterotroph alongside
one kind of autotroph) (requires endomembranes)
- *Variable DNA expression (requires cell-to-cell signalling
or biofilm)
- *DNA methylation (requires variable gene expression)
- Endoplasmic reticulum (allows intracellular transport of various
molecules; requires endomembranes)
- *Nucleus (requires endomembranes)
- *Multiple nuclei (requires nucleus)
- Cellular specialization (requires variable gene expression)
- Temporary colonies (this unicellular organism comes together in a
colonial formation for certain specialized functions, like
reproduction, migration, or surviving hostile conditions; requires cellular
specialization)
- *Alternation of generations (unicellular) (this organism alternates
between different forms with each generation; this may be between a
diploid, asexual generation and a halpoid, sexual generation; between
colonial and solitary generations; or some other kind of alternation)
- Metamorphosis (this organism has multiple distinct stages in its
life cycle, with a physical metamorphosis between them; requires variable
gene expression)
- Clonal colonies (this organism forms permanent colonial units made
up of individual zooids for all or most of its life cycle; each zooid
is a clone of an original “parent” zooid; requires cellular
specialization)
- Syncretic colonies (this organism forms permanent colonial units
made up of individual zooids for all or most of its life cycle;
multiple individuals must join together to found a colony; requires syngamy,
metamorphosis, or temporary colonialism)
- Macroscopic unicellular organism (requires multiple nuclei,
endoplasmic reticulum)
- *Macro-organelles (this organism is a single large cell with many
nuclei; nonetheless, it is capable of specializing parts of itself to
accomplish particular tasks, akin to the distinct tissues of a
multicellular organism; requires macroscopic unicellular organism,
variable gene expression)
- *Multicellular organism (this organism is a true multicellular
organism, with each cell taking over specialized functions; requires
one of syncretic colonies or clonal colonies)
Once a species is evolved with the multicellular or macro-organelles
adaptations, it is considered a multicellular or
macroscopic species (even if it's technically unicellular). All
unicellular traits are fixed, and can't be removed or changed--they are
part of the new species' basic metabolism. Multicellular organisms
evolved from a unicellular line with syngamy or meiosis
may start with sexual reproduction. Extremophiles and
autotrophs retain their specific variety of extremophile and autotroph.
Basic multicellular
adaptations
Multicellular adaptations are suitable for any kind of organism--plant,
animal, fungus, etc. Adaptations can be interpreted widely, and applied
to creatures of any niche, unless noted otherwise. You are not
restricted to evolving species which resemble terrestrial ones.
- Pronounced coloration (choose a color/pattern!)
- Reduplication of body part (choose a part!)
- Overdevelopment of body part (choose a part!)
- Underdevelopment of body part (choose a part!)
- Herbivore
- Carnivore
- Detrivore
- Saprovore
- Electroreception
- Magnetoreception
- Color-changing
- Shape-changing
- +Long-lived
- +Short-lived
- +Increase in size
- +Decrease in size
- Biologically immortal
- Burrowing
- Aerostat
- Hydrostat
- Bioluminescent
- Cave-dwelling
- Rock-breaking
- Semelparous
- Mimicry
- Camouflage
- Metamorphosis
- Pupa or coccoon
- Alternation of generations
- Colonial
- Spikes, spines, thorns, or horns
- Urticating hairs or ability to shoot spines
- Extremophile (has variations thermophile, halophile,
acidophile, psychrophile, radiophile, zerophile, alkaliphile)
- Hair, fur, or fuzz
- Armor or shell
- Thick hide or bark
- Spotted
- Striped
- Produces silk or fiber
- Produces slime
- Produces corrosive fluid
- Seasonal life-cycle
- Flattened body shape
- Branching body shape
- Weird fronds
- Photoreceptors
- Filter feeding
- Wings
- Permanently airborne (requires wings or aerostat)
- Ultra-subterranean (requires burrowing or cave-dwelling)
- Rough or bumpy exterior
- Migration
- Pyrophyte
- Neoteny
- Regeneration
- Detachable body parts
- Suckers
- Stinger or barbed tail
- Precocial
- Altricial
- Sail
- Scales
- Siphon
- Eyestalks (requires some kind of eye)
- Strange mouth shape (requires gut)
- Unusual orifice
- Unusual sense (requires nerve cluster)
- Reef, dike, or mound-formation
Advanced multicellular
adaptations
- Asexual reproduction (has variations budding, fission,
sporogenesis, fragmentation)
- Sexual reproduction (has variations free-floating gametes,
internal fertilization, external fertilization)
- Sex determination (this organism is no longer composed (solely) of
hermaphrodites; you can choose XY, ZW, haploid/diploid, or some other
principle on which to base sex determination; requires sexual
reproduction)
- Egg-laying
- *Musculature
- *Endoskeleton
- *Exoskeleton
- *Fibrous support structure
- *Nerve cluster
- Symbiosis (has variations mutualism, commensalism, parasitism)
- Mycelium (this organism's main body is a mass of fibrous tissue
rather than a single compact body or stem)
- Temporary fruiting bodies (this organism developes a temporary
fruiting body to help disperse its spores, seeds, or gametes; it may
be much more conspicuous than the rest of the organism)
- Passive vascular system (this organism has ways of transporting
nutrients and water through its body passively, via tissues that
resemble xylem and phloem)
- Root system
- Leaves (this organism has distinct flattened tissues to aid in gas
exchange, photosynthesis, or some other crucial metabolic function)
- Woody tissue (this organism has developed some kind of rigid support
structure that allows it to grow to great heights; requires fibrous
support structure, mycelium, or passive vascular
system)
- Seeds
- Taproot (requires root system)
- Flowers (requires seeds)
- Fruit (this organism uses attractive fruits to lure mobile creatures
to distribute its seeds more widely; requires seeds)
- *+Symmetry (choose degree of symmetry: bilateral, 3-fold radial,
4-fold radial, etc.)
- Streamlined body (requires symmetry)
- *Segmentation (this organism’s body is built up out of repeated
segments; they may fuse to form special appendages like the head or
tail, but the segment is the basic unit of the body plan)
- Eyespots (requires photoreceptors)
- Cup eyes (requires eyespots)
- Enclosed eyes (requires cup eye, small brain)
- Lensed eye (requires enclosed eyes)
- Compound eye (requires eyespots, nerve cluster)
- *Small brain (e.g., the handful of neurons of an insect; requires nerve
cluster)
- Eusocial (requires sexual reproduction, small brain)
- Parthenogenesis (at least one sex can sometimes reproduce in the
absence of a mate; requires sex determination)
- Sexual selection (requires sexual reproduction, small
brain)
- *Gut
- *Digestive tract (requires gut)
- Fins (requires musculature)
- Legs (requires musculature)
- Wings (requires musculature)
- Olfactory receptors (requires nerve cluster)
- *Active circulatory system (has variations open,
single-circuit, double-circuit)
- Unusual sense (requires nerve cluster)
- Gills (requires circulatory system)
- Lungs (requires double-circuit circulatory system)
- Peripheral nervous centers (like an octopus; requires small
brain)
- Nesting (requires small brain)
- *Thermoregulation (requires double-circuit circulatory system)
- Teeth (requires digestive tract)
- Ears (requires nerve cluster)
- Beak (requires digestive tract)
- Claws (requires endoskeleton or exoskeleton and
fins, legs, or wings)
- Hooves (requires legs)
- Tongue (requires digestive tract)
- Predation (requires small brain)
- *Large brain (requires small brain)
Adaptations requiring Large
brain
All adaptations past this point require Large brain.
- Short-term planning
- Parental care
- Sleep
- Memory
- Echolocation (requires ears)
- Live birth (requires egg-laying)
- Lactation (requires live birth)
- Ambush hunter (requires predation, short-term planning)
- Sociality (requires memory, short-term planning)
- Swarms or herds (requires sociality)
- Pack hunter (requires sociality, predation)
- Conspecific signalling (whether vocalization, color-changing, or
some other manner of elementary communication; requires sociality)
- Dreams (requires sleep, memory)
- Dominance displays (requires short-term planning, sexual
reproduction)
- Pattern recognition (requires memory)
- Grasping and object manipulation (requires short-term planning
and a usable appendage)
- Emotions (requires pattern recognition)
- Reciprocity (requires emotions)
- Ad-hoc tool use (requires grasping and object manipulation)
- Long-term planning (requires pattern recognition)
- Hierarchy (requires long-term planning)
- Toolmaking (requires long-term planning, ad-hoc tool use)
- Imagination (requires long-term planning)
- Simple utterances (requires imagination, sociality,
reciprocity, conspecific signalling)
- Shared attention (requires simple utterances)
- Cooperative tool use (requires shared attention, toolmaking)
- Self-awareness (requires cooperative tool use, simple
utterances)
Optional rule: The fate of
a self-aware species
If you continue the game past the development of a sentient species,
you may at the start of the next round optionally roll for the fate of
the civilization during the geologically brief period immediately after
it achieves sentience instead. Roll a 1d6, with the following results:
- Rapid growth followed by extinction. One player describes the nature
of the civilization, one player describes its downfall, and one player
describes the nature of the megastructure(s) or the artifact(s) they
leave behind.
- Growth, followed by decline and stasis; this civilization retreats
into enclaves or virtual worlds where it lives as a shadow of its
former self. One player describes the nature of the original
civilization, one player describes the nature of the remnant, and one
player describes any megastructure(s) or artifact(s) they leave behind
for later species to discover.
- Transcendence. This civilization eventually entirely departs its
original homeworld, either because they have built or xenoformed other
artificial habitats more to their liking, or they no longer have a
need for it. One player describes the nature of the civilization, one
player describes its departure, and one player describes the nature of
the megastructure(s) or the artifact(s) they leave behind.
- Decline into pre-sapience. This civilization eventually collapses,
and while a remnant of its people survive, they regress from
sentience. The species loses all traits past toolmaking. One
player describes the nature of the civilization, one player describes
its downfall, and one player describes the nature of the
megastructure(s) or the artifact(s) they leave behind.
- Slow growth. Although this species is sentient, its initial
population growth and/or technological development is slow. It remains
in a pre-agricultural state, rather than pursuing the arts of
civilization.
- Early extinction. This species may have achieved great things, but
unfortunately catastrophe struck while it was still young. Disease or
disaster wiped it out before it had the tools to protect itself, and
it went extinct. One player describes the nature of the civilization
that formed, if any, and another describes the extinction that
followed.
On a 1-4, a mass extinction event also occurs due to the disruption of
the environment as the civilization matures: roll 1d6 for every
species. On a 1-3, they go extinct. On a 4, they survive unscathed. On a
5, the original goes extinct, but a surviving offshoot gains a random
adaptation. On a 6, two surviving offshoots are created
instead of just one.
Rare adaptations
Rare adaptations are normally unavailable, unless you roll the "rare
adaptation" event as a random event. Roll
a 1d20 to select a rare adaptation from this list:
- Collective cognition - individual organisms of
this species are autonomous, but their cognition or consciousness
exists in the collective. Via chemical, electromagnetic, or other
means, individuals engage in complex signaling with one another; this
cognition doesn't necessarily rely on nervous tissue as it's commonly
understood. This adaptation cannot be inherited by a daughter
species.
- Magma-swimmer - this organism's metabolism is so
specialized, and its cellular structure so unusual, it can move
through molten rock with ease.
- Genetic memory - this organism imprints important
memories or somatic adaptations within the non-coding portions of its
DNA, so that its experiences can be passed on to descendants.
- Contact telepathy - this organism has adapted a
complex chemical or eletromagnetic mechanism that is capable of
altering or overriding the nervous system of creatures that come into
physical contact with it.
- Gargantuan size - this organism can grow to
seemingly impossible sizes: hundreds, or even thousands of feet, in at
least one dimension, large enough to be mistaken for part of the
landscape from a distance. This adaptation cannot be
inherited by a daughter species.
- Extremely rare - this organism has traded a
fundamental genetic imperative--spreading its genes as far as
possible--for some kind of extreme hardiness. Whether as part of its
alternation of generations, or a constant property of its population,
it at least occasionally dwindles down to extremely few
numbers--perhaps as small as the single digits. This
adaptation cannot be inherited by a daughter species. Species with
this adaptation cannot go extinct.
- Firebreathing - this organism can spit a mixture of
volatile chemicals that instantly bursts into flame on contact with
air.
- Psychic vampirism - a fundamental part of this
organism's nutrition, reproduction, and/or growth requires preying on
species with advanced neurology by telepathic means. This trait
requires at least one other species with Small brain to
exist; if none does, re-roll. If no species with Small brain remains,
species with this trait will go extinct.
- Ultra-high-altitude flight - this species can
travel high into the atmosphere--into the thermosphere, the exosphere,
or even into a low orbit for a short time. One day it might even
become naturally space-faring, if it can find a way to propel itself
from planet to planet and star to star.
- Immortal consciousness - even if the individual
dies, its mind can survive. Perhaps it exists within the collective
unconscious until it is reincarnated; perhaps it leaves behind a
crystalline essence that descendants can eat to remember its
experiences; perhaps it exploits as-yet-untapped mechanisms of physics
to do so. Requires small brain; otherwise, re-roll.
- Mr. Potato Species - due to a genetic bottleneck, a
freakish kind of autotomy, and effective regeneration mechanisms, this
species can literally swap body parts from one member to another, like
overcharged plant grafting that occurs naturally.
- Omnisexual - this species is capable of a unique
kind of asexual reproduction that epigenetically imprints offspring
with traits of an otherwise totally incompatible mate. The result is
not a true hybrid, as these imprinted traits are not heritable, but it
does allow this species to adapt efficiently to new environments.
Requires sexual reproduction in some form; otherwise,
re-roll.
- Precognition - either this species is so efficient
at processing sensory information, or it can somehow override basic
laws of physics, to allow it to see seconds or milliseconds into the
future--a small but incredibly powerful advantage over the
competition. Requires small brain; otherwise, re-roll.
- Internal transmutation - this organism has at least
one metabolic pathway that utilizes a protein complex with a
specialized site that can exploit quantum-mechanical phenomenon to
directly transmute elements, giving it access to some truly improbable
chemical processes.
- Viral agent - this organism has developed a
symbiosis with an extremely deadly viral agent which lives in its
tissues, and causes fulminant tumors and necrosis in organisms that
try to eat its flesh and/or that come too near. Requires a
multicellular species; otherwise, re-roll.
- Genetic stasis - an unfortunate failure of this
creatures genome has produced an organism for whom almost all
significant mutations are deadly. New daughter species cannot
be created from this species under any circumstances.
- Petrification - this organism can deliver
a prion into the body of other organisms that causes a rapid
conversion of normal tissue into a hard, dead, stony substance.
- Organ scavenging - this organism can
scavenge organelles (if microscopic) or organs (if macroscopic) from
other species and incorporate them into its body, while retaining much
of their function. Perhaps it can only do so with certain specialized
organs, or perhaps it can do this with almost any kind of tissue.
- Wheels - fairly self-explanatory!
- Diaphanous form - all or part of this organism's
body is not composed of truly solid substance--it is a liquid or
gaslike form held together by electric charge or some more unusual
physical force.
Index