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Abstract Single‐nucleotide polymorphisms (SNPs) are preferred over microsatellite markers in many evolutionary studies, but have only recently been applied to studies of parentage. Evaluations ofSNPs and microsatellites for assigning parentage have mostly focused on special cases that require a relatively large number of heterozygous loci, such as species with low genetic diversity or with complex social structures. We developed 120SNPmarkers from a transcriptome assembled usingRNA‐sequencing of a songbird with the most common avian mating system—social monogamy. We compared the effectiveness of 97 novelSNPs and six previously described microsatellites for assigning paternity in the black‐throated blue warbler,Setophaga caerulescens. We show that the full panel of 97SNPs (meanHo = 0.19) was as powerful for assigning paternity as the panel of multiallelic microsatellites (meanHo = 0.86). Paternity assignments using the two marker types were in agreement for 92% of the offspring. Filtering individual samples by a 50% call rate andSNPs by a 75% call rate maximized the number of offspring assigned with 95% confidence usingSNPs. We also found that the 40 most heterozygousSNPs (meanHo = 0.37) had similar power to assign paternity as the full panel of 97SNPs. These findings demonstrate that a relatively small number of variableSNPs can be effective for parentage analyses in a socially monogamous species. We suggest that the development ofSNPmarkers is advantageous for studies that require high‐throughput genotyping or that plan to address a range of ecological and evolutionary questions.
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Novel Quantification of Eggshell Surfaces in Dromaius novaehollandiae With Implications for the Fossil Eggshells of Oviraptorosauria (Dinosauria)
ABSTRACT The external surfaces of non‐avian dinosaur eggs are not usually smooth like those of their avian descendants. Unique ornamentation patterns sculpt the exterior of the eggs, a trait that is difficult to interpret because of its scarcity in modern taxa. One avian species that does homoplastically present similar external eggshell ornamentation to that of non‐avian dinosaurs isDromaius novaehollandiaeLatham, 1790, the emu. Here we useD. novaehollandiaeeggs in conjunction with a clutch of oviraptorosaurian dinosaur eggs (NCSM 33576,Macroelongatoolithus carlylei) to test new methods of quantifying external eggshell ornamentation. Currently, the only scientific language for describing and comparing ornamentation styles in fossil ootaxa is restricted to qualitative categorization, which introduces issues of subjectivity and overly broad and overlapping typification. In this study, we derived and tested a new statistical quantitative approach to quantifying ornamentation that includes two existing functions of the molaR package in R previously applied to shape quantifications of fossil teeth, and ‘Orientation’, a novel function presented as a proxy for ‘direction’, needed to capture directionality. Results demonstrate that (1) the quantitative approach provides statistical backing to gross qualitative observations; (2) statistically significant differences exist between the ornamentation inD. novaehollandiaeandM. carlylei, particularly in terms of relief; (3) intranest variation ofM. carlyleican be demonstrated from harmonic meanp‐value differences between different pairs of eggs. This method offers a strong platform to consolidate quantitative measures with existing qualitative categories, improve the diagnoses of ootaxa and answer broad ecological and evolutionary questions regarding dinosaur reproduction. Moreover, wider application of the technique is encouraged for a multi‐proxy quantitative analysis of any paleontological surfaces, such as echinoderm tests, geological ripple marks or dentition.
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- Award ID(s):
- 1925973
- PAR ID:
- 10599959
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Ecology and Evolution
- Volume:
- 15
- Issue:
- 5
- ISSN:
- 2045-7758
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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