Not all twins are identical and that’s been an evolutionary puzzle, until now

When a mother gives birth to twins, the offspring are not always identical or even the same gender. Known as fraternal twins, they represent a longstanding evolutionary puzzle. Identical twins arise from a single fertilised egg that accidentally splits in two, but fraternal twins arise when two eggs are released and fertilised. Why this would […]

Not all twins are identical and that’s been an evolutionary puzzle, until now Read More »