There is a very unique form of process for the as whole production of the different organisms inside the environment, as there are plant and animal species of which ancestors had a haploid (or half the number of chromosomes as compared to there parents) but they have a diploid form of chromosomes. Which would be certainly possible after the evolution which took place inside there genome and made them able to survive through generation having much similarity to there predecessors and that is how the species survived even though the process of alternation of generation( as explained) happened inside them.
