News from IBE (CSIC-UPF)
In this article researchers from IBE tell the story of a lineage of leaf beetles that originated in the Late Miocene, some 10 Ma ago, in arid, open vegetation environments of the most meridional latitudes of the large island-continent that was North America at the time. This lineage thrived and diversified mostly in Mesoamerica and throughout the Nearctic region reaching the 130 species that we know today, exploiting the newly formed land bridge between North and South America during the Pliocene (some 4 Ma ago) to colonize the Neotropical realm a number of times. Climate change resulting from the formation of the Isthmus of Panama and the contemporaneous build-up of the impressive Rocky Mountain chain, possibly favoured the evolution and diversification of a recent and species-rich North American endemic lineage of these beetles adapted to riverine and lacustrine environments, which quickly developed in the eastern half of the continent during the end of the Pliocene.
They have been studying the genus Calligrapha for 15 years, with a special interest in the alternative reproductive strategies used by different species. Understanding the evolution of complex traits such as reproduction required a solid phylogenetic hypothesis. This article is a big step forward towards this understanding. It also makes us very proud, since it has been only possible after more than one decade trying to cover as much taxonomic diversity as possible from species distributed throughout a whole continent, and a dedicated effort to find suitable molecular characters for the quality of information that our enquiry demanded.
Montelongo, T. & Gómez-Zurita, J. (2014). Multilocus molecular systematics and evolution in time and space of Calligrapha (Coleoptera: Chrysomelidae, Chrysomelinae). Zoologica Scripta, 43, 605-628.