English scientist James Lovelock served as an advisor and his Gaia hypothesis of planet evolution was incorporated into the game.

Versions were made for the Macintosh, Atari ST, Amiga, IBM PC, Super Nintendo Entertainment System, Sega CD, and TurboGrafx-16.

The big (and difficult) challenge is to evolve sentient life and an advanced civilization, culminating in that species leaving the planet in an Exodus.

Mass extinctions, however, are often followed by periods of renewed evolutionary diversification, allowing the player to experiment with new sets of species and ecosystems.

A feature of the game is that all taxa of multicellular animals are on an equal footing, and thus it is possible to evolve, for example, sapient molluscs.

As an "Easter egg", there is also machine life, which can appear if a city of the highest technology level (Nanotech Age) is destroyed by a nuclear explosion.

Machine life can thrive in any biome or environmental conditions, generally out-competing any other lifeforms present, and can itself eventually evolve intelligence and build cities.

"[6] Gaia models link biology and geology however, which Lovelock claimed are "for some reason stable and able to resist perturbations.

"[6] Lovelock expressed that SimEarth's simulation has 'a degree of realism' despite it being "little more than a game", and he expressed that he hadn't seen or been involved in any computer simulations of nature on the scale of SimEarth at the time, noting that many professional climate models at the time didn't take clouds, the ocean, or biology into account.

The reviewer wished that the game had more SimCity-like visual feedback, but stated that it was superior to the predecessor because of larger scope and greater replayability.

[8] Entertainment Weekly gave the game an A− and wrote that "While it's never too early to teach kids to respect the biosphere, the same may not be true of introducing them to complicated simulations such as Simearth: The Living Planet (FCI, for Super NES), which has more variables (temperature, precipitation, etc.)