Combine the given two facts to write a concluding fact. Note that there should be some parts of the first and second facts that are not mentioned in this conclusion fact. Your combined fact should be the result of a chain between the two facts. Chains form when two facts connect together to produce a concluding fact. An example of a chain is: "pesticides cause pollution" (fact1) + "pollution can harm animals" (fact2) → "pesticides can harm animals" (conclusion fact). Parts of the concluding fact overlap with the first and the second fact. To construct such a  concluding fact, a useful way is to borrow the subject from one fact and the ending conclusions from another fact.

Example Input: Fact 1: Behaviors that improve fitness increase through natural selection. 
Fact 2: Many organism behaviors have evolved through natural selection.
Example Output: An organism's fitness is a result of evolution.

Example Input: Fact 1: the surface of a beach is formed by mechanical weathering. 
Fact 2: Most beaches are of white coral sand.
Example Output: Coral is turned to sand by mechanical weathering.

Example Input: Fact 1: nerves can be used to feel heat and pressure on the skin. 
Fact 2: The person with a fever has very warm or hot feeling skin.
Example Output:
A person would have a more difficult time feeling a fever without nerves.