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.
--------
Question: Fact 1: Mollusks are a major food source for other organisms, including humans. 
Fact 2: Many organisms are omnivores with variable diets.

Answer: Humans have variable diets and some consume mollusks as a major food source.


Question: Fact 1: Viruses cause many human diseases. 
Fact 2: Human viruses are created by natural process.

Answer: Something created by a natural process  cause many human diseases.


Question: Fact 1: eyes are used for seeing by animals by sensing light. 
Fact 2: Visible and invisible light is energy in the form of electromagnetic waves.

Answer:
Eyes are used for seeing animals by sensing electromagnetic waves.