The two types of natural selection, and why each fails

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Natural selection comes in two forms, positive and negative. Positive selection is supposed to improve species, but Dr Rob gives a clear example where bad mutations are amplified. Negative selection is supposed to keep species from degrading, but Dr Rob uses the same example to show how it occurs too late. Based on an article from Creation.com.

Notes and links:

• Original Article: creation.com/en/articles/two-forms-natural-selection
• Dr Rob’s bio: creation.com/en/people/dr-robert-carter
• Main Citation: Neville, M.D.C. et al., Sperm sequencing reveals extensive positive selection in the male germline, Nature 2025 | DOI:s41586-025-09448-3 Link: pmc.ncbi.nlm.nih.gov/articles/PMC12611758
• Edwards, C.J. et al., Ancient hybridization and an Irish origin for the modern polar bear matriline, Curr. Biol. 21(15):1251–1258, 2011.