Maybe they came from different groups or mixed semen
Polygenic traits are those traits that are controlled by more than one gene. Such traits may even be controlled by genes located on entirely different chromosomes. Human height, eye and hair color are examples of polygenic traits. Skin color is another polygenic trait for humans and a variety of other animals.
Its important because they produce offspring. Without any offspring the species would slowly die off and become extinct.
Cooperation is the answer because that’s when different organisms work together. Competition is when two from the same species compete for resources/ mates, so that’s not it. Commensalism is an interaction between species, so that’s not it. Consumerism I don’t think has to deal with biology at all.