Species Interactions and Speciation
There are more than 1,000,000 described species of insects and 300,000 of plants. The two groups together comprise most of the terrestrial species on Earth. It is widely thought that interactions between plants and insects, especially herbivory, are responsible for this outstanding diversity.
I am testing this idea using weevils that visit flowers of the licuri palm (Syagrus coronata) as a model system. I am describing the natural history of several species, finding that some are pollinators, some are non-pollinators that feed on live plant tissue and others are non-pollinators that feed on decaying undefended tissues. By using DNA sequencing (RAD-seq), I compared population divergences of these plants and their associated weevils, and found that the mode of interaction is not associated with differences in population divergences. It seems that weevils that cooperate, antagonize or are simply harmless to plants all have very similar patterns of speciation.
In my current postdoc, I am working on a similar problem but for a different kind of species interaction: mosquitoes and their vertebrate hosts.
de Medeiros BAS, Núñez-Avellaneda LA, Hernandez AM, Farrell BD. 2019. Flower visitors of the licuri palm (Syagrus coronata): brood pollinators coexist with a diverse community of antagonists and mutualists. Biological Journal of the Linnean Society 126: 666-687. doi:10.1093/biolinnean/blz008.
None of the organisms I have worked with had available genomic data when I started. For weevils, I have tested a modification of the RAD-seq protocol, including a whole genome amplification step, to obtain genetic data from these small organisms that yield little DNA. To better visualize que quality of data generated and patterns of missing data, I wrote Matrix Condenser, an interactive graphical interface. I have additionally used RAD-seq for sequencing the DNA of palm trees and I am now applying it to the Caribbean genus Aristolochia.
To obtain reference data for building a phylogeny of palm weevils, I have sequenced the transcriptomes of a few species. I then used this data to build probes to enrich genomic regions across 300 samples and I am now working on building a phylogeny from this data.
de Medeiros BAS & Farrell BD. 2018. Whole-genome amplification in double-digest RADseq results in adequate libraries but fewer sequenced loci. PeerJ, 6, p.e5089.
de Medeiros BAS. 2018. Matrix Condenser.
Weevils (beetles in the superfamily Curculionoidea) are one of the most diverse groups of beetles, with over 60,000 species described. It is a challenging group of organisms, with a complicated taxonomy and many new species remaining to be described. While I have many more new species in my to-do list, so far I managed to describe some of them. I have also worked on the morphology and behavior of a species that specializes as a canibal right after the egg hatches, which is unusual in this group comprised mostly of herbivores. My main collaborators in this work are Sergio Vanin, Roberta Valente and Luis Alberto Núñez.
Valente RM, da Silva PAL & de Medeiros BAS. 2019. The first species of Cotithene Voss (Coleoptera: Curculionidae: Curculioninae) from Amazonian Brazil, with notes on its role as a pollinator of Evodianthus funifer (Poit.) Lindm. (Cyclanthaceae). Zootaxa, 4576: 461–482.
de Medeiros BAS, Bená DC & Vanin SA. 2014. Curculio Curculis lupus: biology, behavior and morphology of immatures of the cannibal weevil Anchylorhynchus eriospathae G. G. Bondar, 1943. PeerJ, 2, p.e502.
de Medeiros BA. & Núñez-Avellaneda LA. 2013. Three new species of Anchylorhynchus Schoenherr, 1836 from Colombia (Coleoptera: Curculionidae; Curculioninae; Acalyptini). Zootaxa, 3636(2), pp.394–400.
This is a collaborative work with Seth Donoughe, Sam Church and Cassandra Extavour. We created a database containing over 10,000 records of shape and size of insect eggs retrieved from the primary literature. My main contributions were to create a tool to update and correct spelling of species names by using online databases (TaxReformer) and to build a phylogenetic tree including all insect genera with both genetic and egg data available.
Church SH, Donoughe S, de Medeiros BAS & Extavour CG 2019. Insect egg size and shape evolve with ecology but not developmental rate. Nature 571:58-62. DOI: 10.1038/s41586-019-1302-4
Church SH, Donoughe S, de Medeiros BAS & Extavour CG 2019. A dataset of egg size and shape from more than 6,700 insect species. Scientific Data 6:104. DOI: 10.1038/s41597-019-0049-y
de Medeiros BAS. 2018. TaxReformer.
While an undergraduate student at the University of São Paulo, I studied the harmful effects of night lighting on insects under the supervision of Alessandro Barghini and Sergio Vanin. We found that even small amounts of ultraviolet radiation, in lights that are mostly yellow, can trigger insect attraction, and that UV radiation should be avoided by all means. Using beetles as a case study, we also found that not only a higher number of individuals are attracted to lights with more UV, but also a higher diversity of species. We also wrote a review on the indirect effect of lights in the transmission on vector-borne diseases.
Barghini A & de Medeiros BAS. 2010. Artificial Lighting as a Vector Attractant and Cause of Disease Diffusion. Environmental Health Perspectives 118: 1503–1506.
Barghini A & de Medeiros BAS. 2012. UV Radiation as an Attractor for Insects. LEUKOS 9: 47–56.
de Medeiros BAS, Barghini A & Vanin SA. 2017. Streetlights attract a broad array of beetle species. Revista Brasileira de Entomologia 61: 74–79.
I am currently advising an undergraduate student in a study of the phylogeny of the plant genus Aristolochia in the island of Hispaniola. Previously, I collaborated with Sangil Kim to understand how a single species of Callipogon ended up in Asia, when all of its relatives are in the Americas, and what to expect for its future under climate change. Another project is a collaboration with Altai Pavón, Tauana Cunha and Gonzalo Giribet to study the population genetics of the snail Patella ferruginea.
Kim S, de Medeiros BAS, Byun BK, et al. 2018. West meets East: How do rainforest beetles become circum-Pacific? Evolutionary origin of Callipogon relictus and allied species (Cerambycidae: Prioninae) in the New and Old Worlds. Molecular Phylogenetics and Evolution 125: 163–176.