Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

Ex Input:
The climate is defined as the temperature plus precipitation of an area over a long period of time.

Ex Output:
What is defined as the temperature plus precipitation of an area over a long period of time?

Ex Input:
Exotic species are also called invasive species because they threaten other species.

Ex Output:
Why are exotic species also called invasive species?

Ex Input:
Invertebrates (and higher animals) can also be placed in one of two groups based on how they develop as embryos.

Ex Output:
Invertebrates (and higher animals) can also be placed in one of two groups based on how they develop as what?