For example, every time meat is left to rot, it generates flies. Spontaneous generation gives rise to complex organisms such as flies, animals and even humans. Higher organisms are the result of spontaneous generation, and they don't evolve from other life forms.

Abiogenesis is the theory that life comes from non-living things. Spontaneous generation was an early model for abiogenesis developed by Aristotle (384-322 BCE) which said that flies formed directly from decaying material and logs gave rise to crocodiles. Experiments by Louis Pasteur in the mid-1800’s disproved spontaneous generation.

Examples of primitive prokaryotes still found on Earth today include archaea, which often inhabit extreme environments with conditions similar to those that may have existed billions of years ago, and cyanobacteria (blue-green algae), which also flourish in inhospitable environments and are of particular interest in understanding the origin of life, given their photosynthetic abilities.

Abiogenesis Examples Cell division; flies developing from larvae; baby mice created by adult males and females Spontaneous generation