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Macroevolutionary Rates by Integrating Phylogenomics and Ancestral character States - A study on Neotropical butterfly evolution.

Periodic Reporting for period 1 - MARIPOSAS (Macroevolutionary Rates by Integrating Phylogenomics and Ancestral character States - A study on Neotropical butterfly evolution.)

Periodo di rendicontazione: 2017-01-16 al 2019-01-15

What is the problem/issue being addressed?

We are facing an undeniable global biodiversity crisis. Understanding the impact of environmental disturbances is important but equally so is the understanding of mechanisms that form and maintain current species diversity. The American tropics are the most diverse region on Earth yet most biodiversity research there has largely focused on vertebrates and plants. This project addresses this gap in scientific knowledge by studying the evolutionary history of two species-rich insect groups, skippers and brush-footed butterflies.

Why is it important for society?

Insects are the largest component of biodiversity on Earth with key roles in ecosystem balance. Understanding the ecological and evolutionary processes that intervene in their evolution is important for untangling unknown ecosystem functions and biological interaction among species, as well as for anticipating ecological responses to anthropogenic environmental alterations.

What are the overall objectives?

The overall objectives of the project were:
1. Assemble a genomic dataset for Neotropical skipper and brush-footed butterflies in order to investigate similar evolutionary trajectories.
I pursued this objective by using gene capture and high-throughput DNA sequencing of 350 loci. I met this objective by using bioinformatics pipelines developed by the host to infer the evolutionary history—speciation, extinction and dispersal—of butterflies.

2. Standardize approaches to study biodiversity from the perspective of insect evolution, including high-throughput DNA sequencing and multi-evidence species delimitation.
I pursued this objective by using a multi-disciplinary effort to compile/generate data on geographical distribution, morphological variation and the natural history of butterflies. I met this objective by reviewing public databases and the literature. These datasets are one of the most comprehensive for any tropical butterfly group to date.

3. Generate knowledge that can enrich our understanding of Neotropical extant biodiversity.
I pursued this objective by using multi-line evidence for an ecologically important insect group. I met this objective by utilizing probabilistic models informed by genomic, geographical distribution and morphological data to infer evolutionary processes driving current Neotropical butterfly diversity.

The conclusions of the research are:
1. I found phylogenetic support for a long-standing hypothesis of morphological resemblance among distantly related butterfly species classified in the skipper butterfly’s subfamily Eudaminae.

2. I propose a novel synergistic approach between traditional taxonomy and latest speciation statistical models to robustly delimit butterfly species in the Neotropics.

3. Butterfly phenotypic variability and its geographical distribution in the Neotropics are explained by both 1) neutral processes, such as the rise of the Andes, and 2) intense biological interactions, such as prey-predator interactions driving morphological selection.
The project relied on three pillars: collaborative work, professional development and dissemination of the research results.
1. Collaborative work: The project strengthened a research network among the host institution and EU (Lund University, the Czech Academy of Sciences) and non-EU groups (Smithsonian Institution, Panama; San Marcos University, Peru). Future collaborations emerged thanks to the participation of the host with inter-institutional projects such as the Biodiversity and Ecosystem services in a Changing Climate (BECC, Lund University and University of Gothenburg, Sweden).

2. Professional development: The project contributed to knowledge transfer, including computational and statistical methods to study evolution and biodiversity, high-throughput DNA sequencing methods, presentation and communication skills, and research management. These were ensured by participating in workshops organized by the University of Gothenburg (for example, grant writing and leadership), by the host lab (for example, scientific writing, journal club on ecology and evolution, software development) and by the host Alexandre Antonelli by regular mentorship talks. In addition, the organization and successful execution of a field expedition in Peru for two weeks and the organization of a workshop entitled “Biodiversity research in the light of insect genomics” in Gothenburg in 2017 were important hands-on activities for developing complementary research skills.

3. Dissemination of the research results: The project engaged in dissemination to the scientific community and in communication to the public.

a. Dissemination to the scientific community: Three research articles have been released as open access: i) A perspective on Neotropical biogeography (DOI: 10.7717/peerj.5644) ii) A review on biodiversity research using high-throughput sequencing and insects as model organisms (in press, and a pre-print available at DOI: 10.7287/peerj.preprints.26661v3) iii) A pipeline to delimit butterfly species based on traditional taxonomic knowledge and model-based statistical selection (in press, DOI: 10.1111/syen.12352). Two more manuscripts derived from the action are currently under preparation and all should be submitted for peer-review by Autumn 2019: 1) A phylogenomic backbone for the subfamily Eudaminae (around 150 species), 2) A Neotropical historical biogeography study of Owl butterflies (tribe Brassolini).

b. Communication to the general public: The project was committed to outreach activities. For example, by participating at the European Researchers’ Night in Gothenburg, Sweden, as well as by giving two general talks at the Museum of Natural History in Lima, Peru. Importantly, the contribution of European funding through the European Commission was highlighted in every public event. Furthermore, internet-based communication was achieved by regularly updating a personal website with information about the project (https://pavelmatos.wordpress.com) and by updating Wikipedia in Spanish and English with Neotropical butterfly information on systematics, taxonomy, and evolutionary history (https://en.wikipedia.org/wiki/User:Pavelm14).
The results of the project have moved forward the understanding of insect evolution in the Neotropics, a region that harbors several biodiversity hotspots with extreme levels of species richness and endemism. The phylogenetic information resulting from this research project builds toward a species-level Tree of Life for worldwide butterflies. Moreover, we have shown that the use of valuable and old museum specimens is feasible with high-throughput DNA sequencing.

Overall, this project bridged historical macroevolutionary inference along with extant biodiversity patterns and the results have socio-economic implications. Biodiversity is highly threatened, yet we know little on extant species diversity and how this diversity is maintained, nor even how many insect species exists in tropical regions. This project has contributed to pave the path for future evolutionary and ecological research from the perspective of butterfly biodiversity in the Neotropics.
Pierella Satyr, Pasco, Peru 2017