Can a hybrid be a mutation? If we check the DNA of any organism, excepting clones, aren't all individual organisms unique? Do mutations occur all the time in sexual reproduction? Basically is variation a "slight" mutation?

A portion of your inquiry is accurate: individuals belonging to the same species share the same genome. However, during sexual reproduction, genes are shuffled, resulting in variation. To illustrate this, consider the following simple example: in a card game, there are 52 cards. However, because of shuffles, there are a number of possible combinations, but the total number of cards stays the same. The quantity of cards represents the genome, and the possibilities represent variation. This is not a mutation; rather, it is the expression of a combination of the same genome.

Yes, a hybrid can be a result of mutation if the genetic material from two different species or varieties combines in a novel way. Yes, all individual organisms, except for clones, have unique DNA sequences. Mutations can occur during sexual reproduction, but not all variations are the result of mutations. Variation can include slight mutations, but it can also arise from genetic recombination during meiosis and the mixing of genetic material from two different parents.