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Silent Spring by Rachael Carson sold a lot, but it didn’t have good science.
Her “The Sea Around Us” was much better, but didn’t sell well. She sold out to make money.
I wouldn’t cite SS as an example of good decision making. Because of its DDT bans, a million people a year die of malaria.
DDT at normally doesn’t hurt birds, it helps them, ridding them of bird lice.
No, weakened egg shells wasn’t from DDT.