How do sexual selection and natural selection differ?

Sexual selection is about choosing mates for reproduction, while natural selection is about survival and adaptation to the environment.

Sexual selection and natural selection are two fundamental mechanisms of evolution, but they operate differently. Natural selection is a process where organisms better adapted to their environment tend to survive and produce more offspring. It's about the survival of the fittest. For example, a giraffe with a longer neck can reach more food and is more likely to survive and reproduce, passing on the genes for a longer neck to its offspring.

On the other hand, sexual selection is a type of natural selection where individuals select mates based on certain traits. These traits may not necessarily contribute to survival, but they increase the individual's chances of being chosen as a mate and hence passing on their genes. For instance, peacocks with brighter and larger feathers are more attractive to peahens, even though these extravagant feathers do not aid survival and may even make the peacock more visible to predators.

While natural selection is driven by the environment and survival needs, sexual selection is driven by the preferences of potential mates. It's important to note that these two types of selection can interact and influence each other. For example, a trait that is favoured by sexual selection could become more common in a population, even if it reduces the individuals' chances of survival. Conversely, a trait that enhances survival could become more common, even if it is not favoured by sexual selection.

In summary, while both natural and sexual selection contribute to the evolution of species, they do so in different ways. Natural selection is about survival and adaptation to the environment, while sexual selection is about attracting mates and reproducing.