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1.
Zootaxa ; 5296(4): 501-524, 2023 May 30.
Article in English | MEDLINE | ID: mdl-37518430

ABSTRACT

The lacertid Latastia ornata was known to date only by its holotype collected in 1938 in Bafatá, central Guinea-Bissau. We report new specimens and localities from Guinea-Conakry, a new country record and major range extension of 700 km SE of the type-locality. We provide an updated diagnosis of the species, including the first genetic and osteological data, and confirm that Latastia ornata is closely related to, but distinct from, L. longicaudata based on external morphology, cranial osteology, DNA data and zoogeography.

2.
Mol Ecol Resour ; 21(6): 1850-1865, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33750003

ABSTRACT

Assignment of parentage with molecular markers is most difficult when the true parents have close relatives in the adult population. Here, we present an efficient solution to that problem by extending simple exclusion approaches to parentage analysis with single nucleotide polymorphic markers (SNPs). We augmented the previously published homozygote opposite test (hot), which counts mismatches due to the offspring and candidate parent having different homozygous genotypes, with an additional test. In this case, parents homozygous for the same SNP are incompatible with heterozygous offspring (i.e., "Homozygous Identical Parents, Heterozygous Offspring are Precluded": hiphop). We tested this approach in a cooperatively breeding bird, the superb fairy-wren, Malurus cyaneus, where rates of extra-pair paternity are exceptionally high, and where paternity assignment is challenging because breeding males typically have first-order adult relatives in their neighbourhood. Combining the tests and conditioning on the maternal genotype with a set of 1376 autosomal SNPs always allowed us to distinguish a single most likely sire from his relatives, and also to identify cases where the true sire must have been unsampled. In contrast, if just the hot test was used, we failed to identify a single most-likely sire in 2.5% of cases. Resampling enabled us to create guidelines for the number of SNPs required when first-order relatives coexist in the mating pool. Our method, implemented in the R package hiphop, therefore provides unambiguous parentage assignments even in systems with complex social organisation. We also identified a suite of Z- and W-linked SNPs that always identified sex correctly.


Subject(s)
Genetic Markers , Songbirds , Animals , Female , Genotype , Male , Polymorphism, Single Nucleotide , Reproduction , Songbirds/genetics
3.
Evolution ; 2018 May 15.
Article in English | MEDLINE | ID: mdl-29761484

ABSTRACT

Inbreeding depression plays a major role in shaping mating systems: in particular, inbreeding avoidance is often proposed as a mechanism explaining extra-pair reproduction in socially monogamous species. This suggestion relies on assumptions that are rarely comprehensively tested: that inbreeding depression is present, that higher kinship between social partners increases infidelity, and that infidelity reduces the frequency of inbreeding. Here, we test these assumptions using 26 years of data for a cooperatively breeding, socially monogamous bird with high female infidelity, the superb fairy-wren (Malurus cyaneus). Although inbred individuals were rare (∼6% of offspring), we found evidence of inbreeding depression in nestling mass (but not in fledgling survival). Mother-son social pairings resulted in 100% infidelity, but kinship between a social pair did not otherwise predict female infidelity. Nevertheless, extra-pair offspring were less likely to be inbred than within-pair offspring. Finally, the social environment (the number of helpers in a group) did not affect offspring inbreeding coefficients or inbreeding depression levels. In conclusion, despite some agreement with the assumptions that are necessary for inbreeding avoidance to drive infidelity, the apparent scarcity of inbreeding events and the observed levels of inbreeding depression seem insufficient to explain the ubiquitous infidelity in this system, beyond the mother-son mating avoidance.

4.
PLoS One ; 6(12): e28809, 2011.
Article in English | MEDLINE | ID: mdl-22194918

ABSTRACT

Postcopulatory sexual selection is an important force in the evolution of reproductive traits, including sperm morphology. In birds, sperm morphology is known to be highly heritable and largely condition-independent. Theory predicts, and recent comparative work corroborates, that strong selection in such traits reduces intraspecific phenotypic variation. Here we show that some variation can be maintained despite extreme promiscuity, as a result of opposing, copulation-role-specific selection forces. After controlling for known correlates of siring success in the superb fairy-wren (Malurus cyaneus), we found that (a) lifetime extra-pair paternity success was associated with sperm with a shorter flagellum and relatively large head, and (b) males whose sperm had a longer flagellum and a relatively smaller head achieved higher within-pair paternity. In this species extrapair copulations occur in the same morning, but preceding, pair copulations during a female's fertile period, suggesting that shorter and relatively larger-headed sperm are most successful in securing storage (defense), whereas the opposite phenotype might be better at outcompeting stored sperm (offense). Furthermore, since cuckolding ability is a major contributor to differential male reproductive output, stronger selection on defense sperm competition traits might explain the short sperm of malurids relative to other promiscuous passerines.


Subject(s)
Animals, Wild/physiology , Sexual Behavior, Animal/physiology , Songbirds/physiology , Spermatozoa/cytology , Animals , Female , Male , Reproduction
5.
Mol Phylogenet Evol ; 57(2): 703-9, 2010 Nov.
Article in English | MEDLINE | ID: mdl-20807580

ABSTRACT

The genetic landscape of the European flora and fauna was shaped by the ebb and flow of populations with the shifting ice during Quaternary climate cycles. While this has been well demonstrated for lowland species, less is known about high altitude taxa. Here we analyze the phylogeography of the leaf beetle Oreina elongata from 20 populations across the Alps and Apennines. Three mitochondrial and one nuclear region were sequenced in 64 individuals. Within an mtDNA phylogeny, three of seven subspecies are monophyletic. The species is chemically defended and aposematic, with green and blue forms showing geographic variation and unexpected within-population polymorphism. These warning colors show pronounced east-west geographical structure in distribution, but the phylogeography suggests repeated origin and loss. Basal clades come from the central Alps. Ancestors of other clades probably survived across northern Italy and the northern Adriatic, before separation of eastern, southern and western populations and rapid spread through the western Alps. After reviewing calibrated gene-specific substitution rates in the literature, we use partitioned Bayesian coalescent analysis to date our phylogeography. The major clades diverged long before the last glacial maximum, suggesting that O. elongata persisted many glacial cycles within or at the edges of the Alps and Apennines. When analyzing additional barcoding pairwise distances, we find strong evidence to consider O. elongata as a species complex rather than a single species.


Subject(s)
Coleoptera/classification , Coleoptera/genetics , Phylogeography , Animals , Bayes Theorem , DNA, Mitochondrial/genetics
6.
Mol Ecol ; 16(11): 2333-43, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17561894

ABSTRACT

The challenge in defining conservation units so that they represent evolutionary entities has been to combine both genetic properties and ecological significance. Here we make use of the complexity of the European Alps, with their genetic landscape shaped by geographical barriers and postglacial colonization, to examine the correlation between ecological and genetic divergence. Montane species, because of the fragmentation of their present habitat, constitute extreme cases in which to test if genetically distinct subgroups based on neutral markers are also ecologically differentiated and show local adaptation. In the leaf beetle Oreina elongata, populations show variation in host plant use and a patchy distribution throughout the Alps and Apennines. We demonstrate that despite very strong genetic isolation (F(ST) = 0.381), variation in host plant use has led to differences in larval life-history traits between populations only as a secondary effect of host defence chemistry, and not through physiological adaptation to plant nutritional value. We also establish that populations that are more ecologically different in terms of larval performance are also more genetically divergent. In addition, morphological variation used to define subspecies appears to be mirrored in the population genetics of this species, resulting in almost perfect clustering based on microsatellite data. Finally, we argue from their strong genetic structure and congruent distribution that the subspecies of O. elongata were divided among the same glacial refugia within the Alps that have been proposed for alpine plants.


Subject(s)
Coleoptera/genetics , Adaptation, Physiological , Animals , Coleoptera/physiology , Ecosystem , Evolution, Molecular , France , Genetic Variation , Geography , Ice Cover , Italy , Larva/growth & development , Microsatellite Repeats/genetics , Phylogeny , Switzerland
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