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: Some species of reptiles can go several weeks between meals. 
Fact 2: Snakes are legless reptiles.
Example Output: some snakes can go several weeks between meals.

Example Input: Fact 1: Viruses cause many human diseases. 
Fact 2: Some smallpox viruses are maintained in laboratories.
Example Output: smallpox causes human disease.

Example Input: Fact 1: Energy is passed up a food chain or web from lower to higher trophic levels. 
Fact 2: Food gives energy.
Example Output:
resources from food are passed up a chain or web from lower to higher trophic levels.