Below is an instruction that describes a task, paired with an input that provides further context. Write a response that appropriately completes the request.

### Instruction:
Based on the input, formulate a hypothesis regarding the past.

### Input:
In the 1800s, there was a sharp decline in the population of American bison.

### Response:
My hypothesis is that the sharp decline in the population of American bison in the 1800s was caused by overhunting.