Genetic Variation and Origin of Parthenogenesis in theAspidoscelis cozumelaComplex: Evidence from Mitochondrial Genes

Abstract

Parthenogenesis is a form of clonal reproduction. Eggs develop in the absence of sperm and offspring are genetically identical to their mother. Although common in invertebrates, it occurs in only a few species of squamate reptiles. Parthenogenetic reptiles have their origin in interspecific hybridization, and their populations are exclusively female. Because of its high mutation rate and maternal inheritance, mitochondrial DNA sequence data can evaluate the origin and evolution of all-female vertebrates. Partial sequences from two mitochondrial genes, Cytb and ND4, were analyzed to investigate questions about the origin of parthenogenesis in the Aspidoscelis cozumela complex, which includes A. cozumela, A. maslini and A. rodecki. Low levels of divergence were detected among parthenogenetic species, and between them and A. angusticeps, confirming it as the maternal species of the parthenoforms. A gene tree was constructed using sequences from three populations of A. angusticeps and nine of its unisexual daughter species. The phylogeny suggests that two independent hybridization events between A. angusticeps and A. deppii formed three unisexual species. One hybridization resulted in A. rodecki and the other formed A. maslini and A. cozumela. Although A. cozumela has the haplotype characteristic of A. maslini from Puerto Morelos, it is considered to be a different species based on karyological and morphological characteristics and its geographical isolation.

Parental and hybridDaphniafrom theD. longispinacomplex: long‐term dynamics in genetic structure and significance of overwintering modes

“…In some other hybrid complexes (e.g. grasshoppers (Honeycutt & Wilkinson, ), aphids (Delmotte et al ., ), snails (Johnson & Leefe, ) or lizards (Manríquez‐Morán et al ., )) hybridization can even lead to a complete loss of sexual reproduction, whereas clonal lineages become successfully established. Less successful sexual reproduction in hybrids might have three main consequences for the hybrid populations.…”

Extensive variation in chromosome number and genome size in sexual and parthenogenetic species of the jumping‐bristletail genus Machilis (Archaeognatha)

“…Multiple evolution of parthenogenesis within a genus has been demonstrated in other animal groups such as stick insects (Schwander and Crespi ) and lizards (Manriquez‐Moran et al. ), and these groups offer exciting opportunities for studying evolutionary scenarios leading to parthenogenesis.…”

“…2). Multiple evolution of parthenogenesis within a genus has been demonstrated in other animal groups such as stick insects (Schwander and Crespi 2009) and lizards (Manriquez-Moran et al 2014), and these groups offer exciting opportunities for studying evolutionary scenarios leading to parthenogenesis. In Alpine Machilis species, multiple origins of parthenogenesis may have been facilitated by Pleistocene glaciation cycles, which are thought to have increased the incidence of asexual reproduction in plants and animals (H€ orandl 2009).…”

Multiple interspecific hybridization and microsatellite mutations provide clonal diversity in the parthenogenetic rock lizard Darevskia armeniaca

“…Naturally occurring unisexual reproduction occurs in less than 0.1% of all vertebrate species [1, 2] and true parthenogenesis has been described only in squamates [1, 3–5]. Recently, the origin and evolution of parthenogenesis, in particular in lizards, has received considerable attention [6–13]. Unisexuality usually arises through interspecific hybridization between genetically related sexual species [14, 15] and introgressive hybridization is common among species of lizards Jancuchova-Laskova et al [7].…”