A recent study published in online issue of the Proceedings of the Royal Society B reconstructs a Nymphalid butterfly family tree and reveals family's evolutionary history which has remained a long term mystery due to the lack of butterfly fossils. The age of Nymphalidae butterflies has been the subject of longstanding confusion but according to this new study Nymphalids first evolved 90 million years ago which suprisingly coincides with the global rise of the angiosperms at about 100 million years ago.
Based on sequences of 10 genes and 235 morphological characters for exemplars of 400 of the 540 valid Nymphalid genera representing all major lineages of the family authors have created a robust phylogenetic tree for the Nymphalidae butterfly family which represents the phylogenetic relationships of 400 genera of Nymphalidae based on a maximum likelihood analysis, along with outgroups. Clades representing subfamilies are coloured. (Image Copyright © The Royal Society 2009 )Interestingly the rate of diversification of the family tree or appearance of new Nymphalid species came to a slowdown around the 64 million years ago which coincides with the Cretaceous–Tertiary (KT) event leading to massive extinction of Nymphalid lineages and different species including non-avian dinosaurs. The ancestors of 10–12 lineages of the Neotropical and Oriental regions survived in KT event leading to subsequent elevated speciation rates in the Tertiary. Extinction, which according to many scientists was caused by a massive catastrophic bolide impact, have been further compounded as a result of widespread extinctions of angiosperm host plants in the same period, disrupting obligate butterfly–plant interactions.
