Biology subjects

Lagomarsino, L. P.

Publications and source records attributed to Lagomarsino, L. P..

6 recordsLinked to original sources

bioRxiv2025

Phylogenomics and macroevolution of a florally diverse Neotropical plant clade (Hillieae)

AO_SCPLOWBSTRACTC_SCPLOWHillieae is a group of [~]30 florally diverse, Neotropical epiphyte species. Species richness peaks in southern Central America and taxa display bat, hawkmoth, or hummingbird pollination syndromes. A phylogenetic framework is needed to understand floral and biogeographic evolution. We used target enrichment data to infer a species tree and a Bayesian time-calibrated tree including [~]83% of the species in the group. We inferred ancestral biogeography and pollination syndromes, described species realized bioclimatic niches via a principal component analysis, and estimated significant niche shifts using Ornstein-Uhlenbeck models to understand how different abiotic and biotic variables have shaped Hillieae evolution. We estimated that Hillieae originated in southern Central America 19 Ma and that hawkmoth pollination is the ancestral character state. Multiple independent shifts in pollination syndrome, biogeographic distribution, and realized bioclimatic niche have occurred, though bioclimatic niche is largely conserved. Using generalized linear models, we identify two interactions-- between species biogeographic ranges and pollination syndromes, and between phylogenetic covariance and pollination syndromes-- that additively affect the degree of bioclimatic niche overlap between species. Regional variation in pollination syndrome diversity and patterns of species bioclimatic niche overlap indicate a link between biogeography and species ecology in driving Hillieae diversification and syndrome evolution.

evolutionary biology↗

bioRxiv2022

Increased resolution in the face of conflict: phylogenomics of the Neotropical bellflowers (Campanulaceae: Lobelioideae), a rapid plant radiation

Background and AimsThe centropogonid clade (Lobelioideae: Campanulaceae) is an Andean-centered rapid radiation characterized by repeated convergent evolution of morphological traits, including fruit type and pollination syndromes. While previous studies have resolved relationships of lineages with fleshy fruits into subclades, relationships among capsular species remain unresolved, particularly along the phylogenetic backbone. This lack of resolution has impeded reclassification of non-monophyletic genera, whose current taxonomy relies heavily on traits that have evolved multiple times within the clade. MethodsTargeted sequence capture using a probeset recently developed for the centropogonid clade was used to obtain phylogenomic data from DNA extracted from both silica-dried and herbarium leaf tissue. These data were used to infer relationships among species using concatenated and partitioned species tree methods, as well as to quantify gene tree discordance. Key ResultsWhile silica-dried leaf tissue resulted in generally more and longer sequence data, the inclusion of herbarium samples improved phylogenetic reconstruction. Relationships among baccate lineages are similar to those inferred by previous studies, though they differ within and among capsular lineages. We improve resolution of Siphocampylus, which forms ten groups of closely related species to which we provide informal names that largely do not correspond to current infrageneric taxonomy. Two subclades of Siphocampylus and two individual species are rogue taxa whose placement differs widely across analyses. Gene tree discordance is high. ConclusionsThe first phylogenomic study of the centropogonid clade considerably improves our understanding of relationships in this rapid radiation. Differences across analyses and the possibility of additional lineage discoveries still hamper a solid and stable reclassification. Rapid morphological innovation corresponds with a high degree of phylogenomic complexity, including cytonuclear discordance, nuclear gene tree conflict, and well-supported differences between analyses based on different nuclear loci. Taken together, these results point to a potential role of hemiplasy underlying repeated convergent evolution. This hallmark of rapid radiations is likely present in many other species-rich Andean plant radiations.

evolutionary biology↗

bioRxiv2021

More-curated data outperforms more data: treatment of cryptic and known paralogs improves phylogenomic analysis and resolves a northern Andean origin of Freziera (Pentaphylacaceae)

AO_SCPLOWBSTRACTC_SCPLOWThe Andes mountains of western South America are a globally important biodiversity hotspot, yet there is a paucity of resolved phylogenies for plant clades from this region. Filling an important gap to our understanding of the Worlds richest flora, we present the first phylogeny of Freziera (Pentaphylacaceae), an Andean-centered, cloud forest radiation. Our dataset was obtained via hybrid-enriched target sequence capture of Angiosperms353 universal loci for 50 of the ca. 75 spp., obtained almost entirely from herbarium specimens. We identify high phylogenomic complexity in Freziera, including the presence of data artifacts. Via by-eye observation of gene trees, detailed examination of warnings from recently improved assembly pipelines, and gene tree filtering, we identified that artifactual orthologs (i.e., the presence of only one copy of a multi-copy gene due to differential assembly) were an important source of gene tree heterogeneity that had a negative impact on phylogenetic inference and support. These artifactual orthologs may be common in plant phylogenomic datasets, where multiple instances of genome duplication are common. After accounting for artifactual orthologs as source of gene tree error, we identified a significant, but non-specific signal of introgression using Pattersons D and f4 statistics. Despite phylogenomic complexity, we were able to resolve Freziera into nine well-supported subclades whose evolution has been shaped by multiple evolutionary processes, including incomplete lineage sorting, historical gene flow, and gene duplication. Our results highlight the complexities of plant phylogenomics, which are heightened in Andean radiations, and show the impact of filtering data processing artifacts and standard filtering approaches on phylogenetic inference.

evolutionary biology↗

bioRxiv2020

Phylogeny, classification, and character evolution of tribe Citharexyleae (Verbenaceae)

Premise of the studyTribe Citharexyleae comprises three genera: Baillonia, Citharexylum, and Rehdera. While there is good support for these genera as a clade, relationships between genera remain unresolved due to low sampling of the largest genus, Citharexylum. A molecular phylogenetic approach was taken to resolve intergeneric relationships in Citharexyleae and infrageneric relationships in Citharexylum. MethodsSeven chloroplast regions, two nuclear ribosomal spacers, and six low-copy nuclear loci were analyzed for 64 species of Citharexyleae. Phylogenetic analyses were conducted using maximum likelihood, Bayesian inference, and Bayesian multi-species coalescent approaches. Habit, presence/absence of thorns, inflorescence architecture, flower color, fruit color, and geography were examined to identify diagnostic characters for clades within Citharexylum. Key resultsIntergeneric relationships resolved Rehdera as sister to Citharexylum and Baillonia nested within Citharexylum. Two species, C. oleinum and C. tetramerum, fell outside of Citharexyleae close to tribe Duranteae. There is strong support for seven clades within Citharexylum, each characterized by a unique combination of geography, fruit color/maturation, and inflorescence architecture. ConclusionsBaillonia is included in Citharexylum; Rehdera is retained as a distinct genus. A subgeneric classification for Citharexylum is proposed.

evolutionary biology↗

bioRxiv2020

Herbarium-based phylogenomics reveals that the Andes are a biogeographic barrier for Otoba (Myristicaceae), an ecologically dominant Neotropical tree genus

AimPlant distributions are influenced by species ability to colonize new areas via long-distance dispersal and propensity to adapt to new environments via niche evolution. We use Otoba (Myristicaceae), an ecologically dominant tree genus found in low-to-mid elevation wet forests, as a system to understand the relative importance of these processes within the Neotropics, a region characterized by high species richness and a diversity of biomes. LocationNeotropics and global TaxonOtoba and entire Myristicaceae MethodsWe resolve the first phylogeny of Otoba using targeted sequence capture phylogenomics. We pair this with the most densely sampled phylogeny of Myristicaceae to date, inferred using publicly available data. We then use phylogenetic comparative methods to infer biogeography and examine patterns of niche evolution. ResultsMyristicaceae has an Old World origin, with a single expansion event into the Americas. Divergence dates, fossil evidence, and a notable lack of long-distance dispersal are consistent with a Boreotropical origin of Neotropical Myristicaceae. Mirroring the rarity of dispersal at the family level, Otobas biogeography is marked by few biogeographic events: two expansions into Central America from a South American ancestor and a single dispersal event across the Andes. This limited movement contrasts with rapid climatic niche evolution, typically occurring across geographically proximate habitats. Main conclusionsContrasting with previous studies, long-distance dispersal does not need to be invoked to explain the pantropical distribution of Myristicaceae, nor the biogeography of Otoba. This likely results from the familys relatively large seeds that are dispersed by large-bodied vertebrates. Instead, rapid niche evolution in Otoba has facilitated its occurrence throughout mesic habitats of the northern Neotropics, including the Amazon rainforest and Andean montane forests. Otoba adds to a growing group of Neotropical plant clades in which climate adaptation following local migration is common, implying an important role of niche evolution in the assembly of the Neotropical flora. Significance statementSpecies distributions across the climatically and topographically heterogenous Neotropics are explained by a combination of local adaptation and dispersal. The relative importance of these mechanisms is clade dependent. We find that niche evolution in geographically proximal habitats is much more common than long-distance dispersal to preadapted regions in the tree genus Otoba, which includes both hyperdominant Amazonian species and narrow Andean endemics. The lack of long-distance dispersal is likely due to Otobas large seeds. Our results add to a growing body of literature demonstrating a key role of labile niche evolution across steep environmental gradients in Neotropical plant biogeography.

evolutionary biology↗

bioRxiv2018

Reproductive capacity evolves in response to ecology through common developmental mechanisms in Hawaiian Drosophila

Lifetime reproductive capacity, or the total number of offspring that an individual can give rise to in its lifetime, is a fitness component critical to the evolutionary process. In insects, female reproductive capacity is largely determined by the number of ovarioles, the egg-producing subunits of the ovary. Recent work has provided insights into the genetic and environmental control of ovariole number in Drosophila melanogaster. However, whether regulatory mechanisms discovered under laboratory conditions also explain evolutionary variation in natural populations is an outstanding question. Here we report, for the first time, insights into the mechanisms regulating ovariole number and its evolution among Hawaiian Drosophila, a large adaptive radiation of fruit flies in which the highest and lowest ovariole numbers of the genus have evolved within 25 million years. Using phylogenetic comparative methods, we show that ovariole number variation among Hawaiian Drosophila is best explained by adaptation to specific oviposition substrates. Further, we show that evolution of oviposition on ephemeral egg-laying substrates is linked to changes the allometric relationship between body size and ovariole number. Finally, we provide evidence that the developmental mechanism principally responsible for controlling ovariole number in D. melanogaster also regulates ovariole number in natural populations of Hawaiian drosophilids. By integrating ecology, organismal growth, and cell behavior during development to understand the evolution of ovariole number, this work connects the ultimate and proximate mechanisms of evolutionary change in reproductive capacity.

evolutionary biology↗