Because through natural selection, only the fittest survive. when the fittest come together and reproduce then the species continues and evolves with only the fittest and strongest genes.
The horse and donkey, though closely related by sharing a common ancestor, are different species. They have different number of chromosomes hence pairing of homologous chromosomes during fusion of gametes becomes complicated. The mule will have an extra chromosome from the horse hence will have abnormalities such as sterility. A Mule is unable to reproduce due to this same phenomenon. Homologous chromosomes are not well paired for meiosis I.
Answer: I’m not sure how I am supposed to answer this question but I would just draw an endocrine system and nervous
Explanation:
