Here's why:
* Sexual Reproduction: Most animals reproduce sexually, meaning it requires the combination of genetic material from two parents. This happens through the fusion of male and female gametes (sperm and egg). This process ensures genetic diversity within a species, which is crucial for adaptation and survival.
* Genetic Variation: Sexual reproduction creates offspring with unique combinations of genes from both parents. This genetic variation helps a species survive environmental changes, diseases, and other threats.
* Evolutionary Advantage: Sexual reproduction allows for natural selection to occur. Individuals with beneficial traits are more likely to survive and reproduce, passing on those traits to their offspring. This leads to the evolution of species over time.
Asexual Reproduction: While some animals can reproduce asexually (like some reptiles and insects), this is not the primary mode of reproduction for most animals. Asexual reproduction results in offspring that are genetically identical to the parent, which can limit adaptation and survival in the long term.
In summary, the need for mating in most animals stems from the evolutionary advantages of sexual reproduction, including increased genetic diversity and the ability to adapt to changing environments.