Systematics, Historical Biogeography & Diversification

Soil arthropod community

Diversity in Space & Time

The research focuses on identifying evolutionary origins and relationships among taxa and then evaluating the role of geographic barriers, geo-climatic events, and phenotypic traits on their biogeographic and diversification patterns. We use multiple taxa to study these questions, like terrestrial and freshwater arthropods, large frugivorous birds, and woody plants in peninsular India. These multi-taxa comparisons have given some interesting insights into the evolution of biodiversity in Asia (Joshi and Karanth, 2011, 2012, 2013; Joshi and Edgecombe, 2019; Joshi et al., 2020; Joshi and Kunte, 2022, Bharti et al., 2023, Gopal et al., 2023). 

We found that geographic and geo-climatic processes have played an important role in biogeography and diversification. We found ecologically adaptive and non-adaptive species pairs across taxa, suggesting that natural selection operates differently across multiple ecological axes. This emphasized the need to assess multiple ecological and evolutionary axes while examining diversification patterns and processes. 

During this work, we also discovered many new species, primarily centipedes, in an integrative taxonomic framework (Joshi and Edgecombe, 2013, 2018, Joshi et al., 2020, Joshi and Agarwal, 2021). 

This research broadly lies in the domain of macroecology and macroevolution. Some of the fundamental questions we would be tackling are the following:

1) Do diversification (speciation and extinction) rates vary across clades through time? Does that reflect in the disparity in clade diversity?

2) Do they show adaptive or non-adaptive divergence across multiple axes while diversifying?

3) What are the roles of geo-climatic and ecological processes on diversity dynamics?

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