Given a scientific passage and an answer, generate a question for the given answer.

Passage: Imagine walking in the forest in Figure below . The towering trees have been growing here for hundreds of years. It may seem as though the forest has been there forever. But no ecosystem is truly static. The numbers and types of species in most ecosystems change to some degree through time. This is called ecological succession. Important cases of ecological succession are primary succession and secondary succession. Answer: ecological succession
The numbers and types of species in most ecosystems change to some degree through time and this is called?

Passage: and . The electric force is 39 orders of magnitudes bigger. Answer: 39
How many orders of magnitudes bigger is the electric force?

Passage: The motion of individual molecules in a gas is random in magnitude and direction. However, a gas of many molecules has a predictable distribution of molecular speeds, known as the Maxwell-Boltzmann distribution. Answer: maxwell-boltzmann distribution
What do we call the predictable distribution of molecular speeds found in gas of many molecules?