Generate a series of (instruction, response) pairs that are similar in context and structure to the example provided below. Each pair should consist of a concise instruction followed by an appropriate, detailed response. The instruction should pose a clear task or question, while the response should provide a comprehensive answer or solution that could be understood by someone with a basic understanding of the subject.

Example pair: 
Instruction: Summarize the following story in a few sentences.

Once upon a time, a farmer had a goose that laid one golden egg every day. The egg provided enough money for the farmer and his wife to support their daily needs. The farmer and his wife continued to be happy for a long time.
But, one day, the farmer thought to himself, “Why should we take just one egg a day? Why can’t we take them all at once and make a lot of money?” The farmer told his wife his idea, and she foolishly agreed.
Then, the next day, as the goose laid its golden egg, the farmer was quick with a sharp knife. He killed the goose and cut its stomach open, in the hopes of finding all its golden eggs. But, as he opened the stomach, the only thing he found was guts and blood.
The farmer quickly realized his foolish mistake and proceeded to cry over his lost resource. As the days went on, the farmer and his wife became poorer and poorer. How jinxed and how foolish they were
Response: A farmer owned a goose that laid a golden egg each day, which he would sell to provide for himself and his wife. One day, the farmer and his wife decided to kill the goose in the hope of claiming all of the goose's golden eggs at once, but they found only guts and blood. The farmer cried over his loss and, as time went on, the man and his wife became progressively more impoverished.

Your task is to generate more pairs that maintain this level of clarity and detail. The topic is Summarization. Write a long text of instruction by yourself, then summarize the given instruction in a response. Ensure that the responses are informative and accurate, suitable for an educational context. 

Store the generated pairs in valid JSON format, with each pair as an object within an array. Each object should have two key-value pairs: "instruction" and "response". For instance: 

{"contents": [{"instruction": "text", "response": "text"}, {"instruction": "text", "response": "text"}, ...]} 

Remember to maintain consistency in the format and ensure the generated pairs are diverse and cover a broad range of subjects. You must return the response in the asked format and you must not add any additional text in your response.

Summarize the theory of evolution by natural selection.
user
Charles Darwin's theory of evolution by natural selection suggests that species evolve over time through a process where traits that enhance survival and reproduction become more common in successive generations. Organisms produce more offspring than can survive, leading to competition for resources. Those with advantageous traits are more likely to survive and reproduce, passing these traits to their offspring. Over long periods, this gradual change leads to the emergence of new species.
assistant