In the last decade and a half, advances in genetic sequencing technologies have revolutionized systematics, transforming the field from studying morphological characters or a few genetic markers, to genomic datasets in the phylogenomic era. A plethora of molecular phylogenetic studies on many taxonomic groups have come about, converging on, or refuting prevailing morphology or legacy‐marker‐based hypotheses about evolutionary affinities. Spider systematics has been no exception to this transformation and the inter‐relationships of several groups have now been studied using genomic data. About 51 500 extant spider species have been described, all with a conservative body plan, but innumerable morphological and behavioural peculiarities. Inferring the spider tree of life using morphological data has been a challenging task. Molecular data have corroborated many hypotheses of higher‐level relationships, but also resulted in new groups that refute previous hypotheses. In this review, we discuss recent advances in the reconstruction of the spider tree of life and highlight areas where additional effort is needed with potential solutions. We base this review on the most comprehensive spider phylogeny to date, representing 131 of the 132 spider families. To achieve this sampling, we combined six Sanger‐based markers with newly generated and publicly available genome‐scale datasets. We find that some inferred relationships between major lineages of spiders (such as Austrochiloidea, Palpimanoidea and Synspermiata) are robust across different classes of data. However, several new hypotheses have emerged with different classes of molecular data. We identify and discuss the robust and controversial hypotheses and compile this blueprint to design future studies targeting systematic revisions of these problematic groups. We offer an evolutionary framework to explore comparative questions such as evolution of venoms, silk, webs, morphological traits and reproductive strategies.
Modern genomic techniques have enabled the generation of phylogenetic datasets of unprecedented scale. However, there are also troves of molecular data accumulated from past studies using Sanger sequencing, often at fine taxonomic scales. Combining both sources of data is an obviously appealing possibility, but it can also lead to inconsistency due to high levels of missing data, disparities in the scale of Sanger versus genomic datasets, and little overlap in sequences across terminals. To provide an empirical investigation of the potential of such ‘hybrid’ datasets, we combined data from ultraconserved elements (UCEs) for 183 species of Cryptini (Ichneumonidae, Hymenoptera) with a previously existing dataset of 7 loci and morphological data including 308 species plus outgroup taxa. Bioinformatics pipelines allowed recovery of ‘legacy’ markers from the bycatch of UCE sequencing, reducing the problem of limited character overlap. The resulting tree combining Sanger and UCE data is highly supported and includes dense taxon sampling of the group, allowing for a better understanding of the global radiation of Cryptini. The Neotropical region had the highest phylogenetic diversity but the lowest level of phylogenetic dispersion when corrected for standardized effect size, while the Oriental fauna showed the highest level of phylogenetic dispersion. Our results highlight the potential of hybrid datasets to produce a more complete picture of the Tree of Life combining affordability, robust support and deep taxonomic sampling.
more » « less- PAR ID:
- 10482784
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Zoologica Scripta
- Volume:
- 53
- Issue:
- 3
- ISSN:
- 0300-3256
- Format(s):
- Medium: X Size: p. 338-357
- Size(s):
- p. 338-357
- Sponsoring Org:
- National Science Foundation
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