Dangers in Spore are things which are out to hinder the player's progress such as an evolving creature or advancing race, and must be overcome to evade the penalty of the death of a creature or collapse of a civilization.
Cell stage
Enemies in the Cell stage are generally other micro-organisms (microbes) that are stronger than the player's own microbe. Other things are currents and obstacles that float around.
A user-created cell under attack by an omnivorous Bloato cell.
Creature stage
Don't ever venture too far out into the waters, or your doom will come!
Other creatures in the Creature stage may attack the player's creature either because the creature is a suitable food source, or because it is trespassing on their territory. Creatures will also attempt to attack the player's eggs until they hatch. Another danger is starvation. If a creature does not eat over time,the hunger meter (orange) will drop, and if you don't eat when it reaches the bottom, the health meter will gradually drop untill the player's creature dies. Other dangers are meteorite rains that willl hurt your creature and stuns it for a while, and UFO's that will abduct other organisms. The Sea Monster will eat the players creature if the creature ventures to far into the water and don't forget about Epics.
Tribal stage
an Epic creature in the tribal stage.
In the Tribal stage, enemy tribes can attack the player's tribe. Another possible danger, similar to the Creature stage, is a lack of food and UFO's. Another threat to a beginning tribe is epic creatures.
Civilization stage
In the Civilization stage, other cities can send various types of vehicles to destroy the player's cities. Epic Creatures can cause problems too.
If you run out of money with no increase to it (drive) can be a problem (more likely to happen in hard mode).
Also timing is important, one wrong move, and you could wreck your path towards space.
Space stage
In the Space stage, alien species may be dangers to the player's species. Focusing on the negatives of alien species, aliens can attack the player's UFO, home planet, colonies, etc. for a variety of reasons (revenge, hostile takeover). But this is not to say all aliens pose threats, just the more aggressive ones. Planetary dangers can pose a danger to starships or even epics will attack although easily defeated they can pose a threat to beginners. Natural disasters like bio-collapses can also occur.
Death(Creature to Space)
Creature stage Death
A creature can be killed by a predator or an overly defensive animal, or it can die of hunger. You lose some DNA in your progress bar (Creature Stage), this is unconfirmed, but your progress bar does turn red when being reborn. When you get killed, you simply are reborn at your creature's nest. You also will not receive the Survivor achievement. However, there is a bug that occurs when you die while migrating that causes the screen to go black, and you have to close the game and restart from your last save.
Tribal stage Death
Death occurs when your hut is destroyed or when all tribe members, including the chieftain, are killed. You will have to load your latest saved game, or if you didn't saved at all, restart the entire stage again by going 'back in time' as it is said in game.
The Chieftain is an important unit in this stage. When it dies it gets resurrected after a period of time. If one of your tribe members dies (not including your chieftain), you will have the option to buy another one for ten of your resources. You will also not receive the Watchful Parent achievement.
Civilization stage Death
When all your cities are destroyed or taken over you will have to restart the entire stage again, which is a severe penalty. However, if you have saved a game you can quit without saving and start from where that saved game occurred at.
Space stage Death
When your UFO gets destroyed in combat, your city simply produces another one (instantly). There is no real death penalty for losing your UFO.
When the player dies they are "cloned" and respawn at the nearest planet of their own empire to the point where they died.
If your home planet is destroyed, you are given one colony to start fresh.
However there is no way to "DIE" in the stage because your empire can never be fully be destroyed, but it is possible to become stuck with low funds when all you have is one city in your home world left, making it hard to do much of anything.
(Un)Achievment
If you die in each stage, you will get the Can't Win For Losing achievment.