system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How did weed strains become increasingly more potent since the 70s?
gpt
Ever notice how friggin' gigantic some strawberries are? It's because of selective breeding. Take the biggest strawberry from a bunch of strawberries, pollinate it with the second-largest, and then plant its seeds, and hopefully the gene that caused it to be massive will be hereditary and be passed on to at least one of its offspring. Now take the biggest strawberry from that group, plant its seeds, and repeat until you have those fist-sized strawberries you can get from some grocery stores.

Weed is the same idea, just apply it to the THCA content in mj leaves. Plant, identify, replant, identify, replant, identify, and so on.