Ecology 1 (1)

It is the study of relationships of organisms to their environments (biotic and abiotic).

All surroundings of an organism, both abiotic and biotic.

The Sand Darter is an aquatic fish, but is found only in flowing water over sand.

Species will survive within a range of the variation of environmental factors. 

• Organisms may die so go extinct from the area until it can re-invade.
• Survive if a life history stage can withstand the change.
• Survive if it moves to protected microhabitats.
• Survive if it migrates.
• Survive if it can acclimate.

is a gradual change into new environmental conditions.

When several variables are important and present, the success of the organisms will depend on the variable present as "too little" or "too much".