According to the question, if a sperm cell contains 8 chromosomes, it indicates that the animal it originates from has 16 chromosomes. This can be explained through the process of meiosis and fertilization.

- Meiosis: Meiosis is a type of cell division that occurs in the reproductive cells (gametes) of organisms. It involves two rounds of division, resulting in the formation of four daughter cells, each with half the number of chromosomes as the parent cell. This process is crucial in creating genetic diversity.

- Chromosome pairing: During meiosis, the chromosomes in the parent cell undergo pairing, known as synapsis. This pairing allows for the exchange of genetic material between homologous chromosomes through a process called crossing over.

- Homologous chromosomes: Homologous chromosomes are chromosome pairs that contain genes for the same traits. In diploid organisms, such as animals, each homologous pair consists of one chromosome inherited from each parent.

- Reduction in chromosome number: Meiosis I is the stage where homologous chromosomes separate, resulting in two daughter cells. Each daughter cell contains half the number of chromosomes as the parent cell. In this case, if the sperm cell has 8 chromosomes, it indicates that the parent cell (spermatocyte) had 16 chromosomes.

- Creation of sperm cells: Meiosis II is the second round of division, where sister chromatids separate, resulting in four haploid cells. These haploid cells are the sperm cells (spermatozoa) in animals. Each sperm cell contains half the number of chromosomes as the parent cell, which in this case is 8 chromosomes.

- Fertilization: During sexual reproduction, fertilization occurs when a sperm cell fuses with an egg cell (ovum). Both the sperm cell and the egg cell contribute half the number of chromosomes to form a diploid zygote. In this case, if the sperm cell has 8 chromosomes, the egg cell would also contribute 8 chromosomes, resulting in a total of 16 chromosomes in the zygote.

Therefore, based on the information provided, if a sperm cell contains 8 chromosomes, it suggests that the animal it originates from has 16 chromosomes.