TRAY WORLDS
Exoplanet Ecosystem Simulator
Watch ecosystems on
different exoplanets based on real biological models
Tigers are on earth orange, because most of their prey is color blind to green and orange colors (e.g. deer), so from perspective of their prey tiger is the same color as plants. And since mammals due to their evolutionary history don't have green pigment, but they do have red/orange/yellow pigment, camouflage color in yellow/orange/red range is the best alternative to green for tiger. You can read more in research paper DOI: https://doi.org/10.1101/428193 .
That also means that on exoplanets, where plants are not green, tigers in general will not be orange. If we assume similar evolutionary history of tiger and its prey as on earth and also assume convergent evolution around maximum of energy distribution of star's spectrum we can take a guess at tigers color on such an exoplanet.
Color of plant leaves on an exoplanet depends primarily on the temperature of its sun. This was discovered in 2020 in research paper DOI:10.1126/science.aba6630 . Below are examples of four stars where I show how a jungle would look on these stars' planets based on this research. Click on images below to view videos.
Red star Proxima Centauri is the nearest star to our Sun. It has temperature of 3,042 K which means plants on planets orbiting the star should be red.
Pollux is a giant orange star with temperature of 4,586 K. This temperature will cause plants to be orange.
Canopus is the second brightest star in the sky. It has temperature of 7,400 K. This means plants will be light gray. But it should be noted, that this star is too young and will not live long enough for plants to evolve. But there are many stars (though less known) with similar temperature that do have lifespans that would facilitate plant evolution.
Altair has temperature of 7,700 K. Plants on planets orbiting a star with this temperature would be pink. Altair (like Canopus) is also probably not sufficiently long-lived to sustain evolution of plants and animals.
This simulator is being built with Unreal Engine, but you can download old version built in Unity here, which explains some of the core concepts.
