Hybrid species are organisms that result from the mating of two different species. This can occur naturally in the wild or through human intervention, such as in agriculture or animal breeding. Hybrids often exhibit traits from both parent species, which can lead to unique characteristics. Common examples include the liger, a cross between a lion and a tiger, and the mule, which is a hybrid of a horse and a donkey. While hybrids can sometimes be fertile, many are sterile, meaning they cannot reproduce. This is due to differences in the number of chromosomes between the parent species. Hybrid species can play important roles in ecosystems, but they may also pose challenges, such as when they outcompete native species or disrupt local biodiversity.