Evolution starts with the embryo

Darwin’s theory of natural selection is not the only method of evolution. Research shows that some evolutionary traits in animals can occur from embryo development through to adulthood.

The researchers used a roundworm species. They changed just two genes: this caused females to become self-fertile hermaphrodites.

Self-fertile hermaphrodite roundworms were found to produce smaller sperm than their male counterparts. Because the animals were in a controlled laboratory setting, natural selection could not have played a part.

Read more at University of Medicine and Dentistry of New Jersey