Infanticide is an excellent example why darwinism should be understood as a fact of nature, not as a model by which we should behave ourselves. Failing to make this distinction has a lot to do with the popularity of creationism (belief that accepting evolution  leads to accepting immorality) and even a lot of non-creationist right wing thinking (social darwinism). The natural order of things isn't necessarily good or desirable.

Although the mechanics are theoretically beautiful, in real life darwinism is ugly, brutal and horrible. Even though we and the diverse life around us is the product of it, darwinistic evolution is the cruellest game in the universe by any human standard. It should be studied, understood and overcome whenever necessary.