Biology subjects

Ghanavi, H. R.

Publications and source records attributed to Ghanavi, H. R..

5 recordsLinked to original sources

bioRxiv2024

Phylogenomics resolves the relationship and the evolutionary history of planthoppers (Insecta: Hemiptera: Fulgoromorpha)

Planthoppers (Hemiptera: Fulgoromorpha) are a species-rich and globally distributed insect clade with high economic, ecological, and evolutionary importance. However, the relationships among planthopper lineages and families remain unclear. Previous efforts based on inconsistent morphological traits, a few genes, or limited sampling often resulted in conflicting tree topologies. Here, we used genome-level data to assemble 1164 nuclear single-copy genes and 13 mitochondrial protein-coding genes for 149 planthopper species representing 19 out of 21 extant families. Additional markers were added from published mitogenomes, expanding our sampling to 285 species. These markers were used for Maximum Likelihood-based tree inference and dating analyses. The newly inferred phylogenies validated well-accepted relationships and recovered novel placements. Taxonomic conclusions include the establishment of a new family Borysthenidae stat. rev. within Delphacoidea and a new superfamily Meenoploidea superfam. nov. including redefined Kinnaridae stat. rev. and Meenoplidae stat. rev., the confirmation of the monophyletic family Achilixiidae outside the Achilidae-Derbidae clade, and the transfer of tribes Lyncidini and Amyclini to Dictyopharidae and the genus Madagascaritia to Fulgoridae. The time analyses based on 57 nuclear markers and 30 fossils dated the origin of crown Fulgoromorpha back to Guadalupian, Permian ([~]263 Ma), close to the maximum constraint at 267.3 Ma, while applying an older root constraint resulted in an origin in Mississippian, Carboniferous ([~]332 Ma). While future sampling of unstudied fauna in unexplored regions or habitats may change the topology, the current phylogenomic analysis will serve as a solid foundation for research into planthopper ecology, evolution, and significance.

evolutionary biology↗

bioRxiv2023

Genomes From 25 Historical Drosophila melanogaster Specimens Illuminate Adaptive and Demographic Changes Across More Than 200 Years of Evolution

The ability to perform genomic sequencing on long-dead organisms is opening new frontiers in evolutionary research. These opportunities are especially profound in the case of museum collections, from which countless documented specimens may now be suitable for genomic analysis. Here, we report 25 newly sequenced genomes from museum specimens of the model organism Drosophila melanogaster, including the oldest extant specimens of this species. By comparing historical samples ranging from the early 1800s to 1933 against modern day genomes, we document evolution across thousands of generations, including time periods that encompass the species initial occupation of northern Europe and an era of rapidly increasing human activity. At the genome-wide level, we find that historical flies from the same time and place show much greater evidence for relatedness than flies from modern collections, and some show evidence of inbreeding as well, potentially reflecting either much smaller local population sizes in the past or else the specific circumstances of the collections. We also find that the Lund, Sweden population underwent local genetic differentiation during the early 1800s to 1933 interval (potentially due to accelerated drift) but then became more similar to other European populations thereafter (potentially due to increased migration). Within each time period, our temporal sampling allows us to document compelling candidates for recent natural selection. In some cases, we gain insights regarding previously implicated selection candidates, such as ChKov1, for which our inferred timing of selection favors the hypothesis of antiviral resistance over insecticide resistance. Other candidates are novel, such as the circadian-related gene Ahcy, which yields a selection signal that rivals that of the DDT resistance gene Cyp6g1. These insights deepen our understanding of recent evolution in a model system, and highlight the potential of future museomic studies.

evolutionary biology↗

bioRxiv2022

The phylogenetic placement of an enigmatic moth Egybolis vaillantina based on museomics

Here, we present multi-locus sequencing results from the enigmatic Afrotropical monotypic genus Egybolis Boisduval (occurring in East- and South Africa - previously placed in the subfamily Catocalinae, Noctuidae). Model-based phylogenetic analysis places Egybolis within a strongly supported clade comprising four Old World Tropical genera Cocytia Boisduval, Avatha Walker, Anereuthina Hubner and Serrodes Guenee from the family Erebidae, subfamily Erebinae. Hence, we propose to formally assign the monotypic genus Egybolis to the subfamily Erebinae, and the tribe Cocytiini. Timing of divergence analysis reveals the late Oligocene origin around 25 million years ago (mya) for the tribe Cocytiini, an early Miocene i.e., about 21 mya for the split between Cocytia and Egybolis.

evolutionary biology↗

bioRxiv2021

Exploring bycatch diversity of organisms in whole genome sequencing of Erebidae moths (Lepidoptera)

Models estimate that up to 80% of all butterfly and moth species host vertically transmitted endosymbiotic microorganisms, which can affect the host fitness, metabolism, reproduction, population dynamics, and genetic diversity, among others. The supporting empirical data are however currently highly biased towards the generally more colourful butterflies, and include less information about moths. Additionally, studies of symbiotic partners of Lepidoptera predominantly focus on the common bacterium Wolbachia pipientis, while infections by other inherited microbial partners have more rarely been investigated. Here, we mine the whole genome sequence data of 47 species of Erebidae moths, with the aims to both inform on the diversity of symbionts potentially associated with this Lepidoptera group, and discuss the potential of metagenomic approaches to inform on their associated microbiome diversity. Based on the result of Kraken2 and MetaPhlAn2 analyses, we found clear evidence of the presence of Wolbachia in four species. Our result also suggests the presence of three other bacterial symbionts (Burkholderia spp., Sodalis spp. and Arsenophonus spp.), in three other moth species. Additionally, we recovered genomic material from bracovirus in about half of our samples. The detection of the latter, usually found in mutualistic association to braconid parasitoid wasps, may inform on host-parasite interactions that take place in the natural habitat of the Erebidae moths, suggesting either contamination with material from species of the host community network, or horizontal transfer of members of the microbiome between interacting species.

genomics↗

bioRxiv2021

The (non) accuracy of mitochondrial genomes for family level phylogenetics: the case of erebid moths (Lepidoptera; Erebidae)

The use of molecular data to study evolutionary history of different organisms, revolutionized the field of systematics. Now with the appearance of high throughput sequencing (HTS) technologies more and more genetic sequence data is available. One of the important sources of genetic data for phylogenetic analyses has been mitochondrial DNA. The limitations of mitochondrial DNA for the study of phylogenetic relationships have been thoroughly explored in the age of single locus phylogenies. Now with the appearance of genomic scale data, more and more mitochondrial genomes are available. Here we assemble 47 mitochondrial genomes using whole genome Illumina short reads of representatives of the family Erebidae (Lepidoptera), in order to evaluate the accuracy of mitochondrial genome application in resolving deep phylogenetic relationships. We find that mitogenomes are inadequate for resolving subfamily level relationships in Erebidae, but given good taxon sampling, we see its potential in resolving lower level phylogenetic relationships.

evolutionary biology↗