An interesting unsolvable puzzle to the evolutionists to explain is the phenomena of parthenogenesis. The origin of the word are the Greek words "parthenos" (virgin) + "genesis" (generation) what all-together means reproduction of usually female gamete (egg) without pollination or fertilization. Parthenogenesis mostly occurs in lower plants and according to statistics of all plants 80% display some form of asexual reproduction and approximately 50% are mainly or exclusively asexual. Amazingly the offspring is genetically or with other words in all inherited respects identical to the mother plant having e.g. egg with an unreduced chromosome number.
Now, the puzzle in all this is that how did evolution continued at all from this kind of plants if these species cannot reshuffle genes to produce subspecies variations? With other words, how evolution developed without meiosis or the absence of cell division that results in two daughter cells each with half the chromosome number of the parent cell. If this could not somehow happen that means that practically there was no possibility of development of sexes.
Actually, the discussion about how the first fully functional female and the first fully functional male developed to begin the process of reproduction, is not the favorite topic of discussion in the circle of the evolutionists. Graham Bell in his book, The Masterpiece of Nature: The Evolution of Genetics and Sexuality, describes the problem in the following way:
"Sex is the queen of problems in evolutionary biology. Perhaps no other natural phenomenon has aroused so much interest; certainly none has sowed as much confusion. The insights of Darwin and Mendel, which have illuminated so many mysteries, have so far failed to shed more than a dim and wavering light on the central mystery of sexuality, emphasizing its obscurity by its very isolation."
In this regard Dobzhansky and his colleagues made an interesting remark:
"With respect to the origin of sexual reproduction, two challenging questions present themselves. First, in what kinds of organisms did sex first arise? And second, what was the adaptive advantage that caused sexual reproduction to become predominant in higher organisms?"
Now in the following section of this essay we would like to describe briefly the how different evolutionary theories attempt to solve the above-mentioned problems but of course ultimately without any success.