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Natural selection
Sex in the animal kingdom takes on many forms. Why are there so many ways of ‘doing it’?
Evolution has given rise to some pretty unique sex strategies that help animals select the mate with the strongest genes meaning their offspring will have the best start in life.
The earliest single-celled organisms didn’t reproduce sexually, but through creating exact replicas of themselves in a process called binary fission. It’s a very efficient way to reproduce, but with no genetic difference between parent and offspring any weakness is passed on to the next generation. Around a billion years ago, the sexual revolution began when these single-celled organisms began exchanging genetic information.
From this point on, new combinations of genetic characterists allowed evolution to leap forward, leading to different sexes and the incredible variety of species we see today.
Earth Unplugged’s Maddie Moate explores the variety of selection in the natural world and explains how it came to be.