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Lost sex: multilocus DNA evolution the hybrid fish complex C.taenia (Teleostei)
Choleva, Lukáš ; Janko, Karel (advisor) ; Mikulíček, Peter (referee) ; Hulva, Pavel (referee)
12 General summary "It is unwise to intrude the suggestion of parthenogenesis, even of a modified sort, into vertebrate literatures. The phenomenon is so at variance with what is known and beleived about vertebrates development that I am sure no vertebrate morphologists would admit for a moment that the natural development from egg to sexual maturity of an individual vertebrate without the direct inclusion of the male element is within the realm of probability", reacted the morphologist Howell (1933. Science 77: 389-390) sarcastically on the discovery of the first recognized asexual vertebrate, a live-bearing fish Poecilia formosa (Hubbs et Hubbs 1932. Science 30: 628-630). "The examples of parthenogenesis has been reported in almost all vertebrate groups," (Lampert 2008. Sexual Development 2: 290-301). The ongoing effort to explain the widespread occurrence of sexual reproduction among animals is often called the "queen of problems in evolutionary biology", and there is still no consensus regarding the explanation. Simultaneously, asexual reproduction exists among some animals. Here, the 'asexuality' refers to any reproductive process that does not involve sex (Mendelian meiosis is mising), except self-fertilization. One individuum produces a progeny genetically identical to its parent, except those sites...
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