- Scientists studied fish from many lakes over several years.
- Some lakes had contamination from a common insecticide.
- Polluted lakes had very few older fish remaining.
- Clean lakes still had many older fish living.
- Lab tests gave fish low insecticide doses over time.
- Low doses made fish show faster signs of getting old.
- Brief high doses caused quick death, not getting old.
- Losing older fish can harm reproduction and stability.
- The results raise concern for other animals and people.
Difficult words
- scientist — A person who studies nature or animals.Scientists
- contamination — Dirty or harmful material in water or land.
- insecticide — A chemical that kills insects.
- dose — A small amount of a medicine or chemical.doses
- reproduction — The process of having new animals or plants.
- stability — The state of being steady or not changing.
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- Do you live near a lake?
- Are you worried about water pollution?
- Have you seen older fish in a lake?
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