Fossil record of stem groups employed in evaluating the chronogram of insects (Arthropoda: Hexapoda)

Abstract

Insecta s. str. (=Ectognatha), comprise the largest and most diversified group of living organisms, accounting for roughly half of the biodiversity on Earth. Understanding insect relationships and the specific time intervals for their episodes of radiation and extinction are critical to any comprehensive perspective on evolutionary events. Although some deeper nodes have been resolved congruently, the complete evolution of insects has remained obscure due to the lack of direct fossil evidence. Besides, various evolutionary phases of insects and the corresponding driving forces of diversification remain to be recognized. In this study, a comprehensive sample of all insect orders was used to reconstruct their phylogenetic relationships and estimate deep divergences. The phylogenetic relationships of insect orders were congruently recovered by Bayesian inference and maximum likelihood analyses. A complete timescale of divergences based on an uncorrelated log-normal relaxed clock model was established among all lineages of winged insects. The inferred timescale for various nodes are congruent with major historical events including the increase of atmospheric oxygen in the Late Silurian and earliest Devonian, the radiation of vascular plants in the Devonian, and with the available fossil record of the stem groups to various insect lineages in the Devonian and Carboniferous.

Phylogeny and the colourful history of jewel bugs (Insecta: Hemiptera: Scutelleridae)

“…In addition, to assess whether the prior distribution was sufficiently wide, a ‘null analysis’ without sequence data was also conducted (Bouckaert et al., ; Wang et al., ,b). The only difference was that the sequences were replaced with missing data, NNNN.…”

To be or not to be: postcubital vein in insects revealed by microtomography

“…Although thousands of fossil insects have been described over the last 20 years, these extinct taxa are included in phylogenetic analyses only rarely enough (Misof et al, 2014;Wang et al, 2016). They are merely used for their temporal dimension as calibration points in dating estimates, whereas they can also bring original evolutionary evidence (i.e.…”

Comparative Transcriptomics in Two Extreme Neopterans Reveals General Trends in the Evolution of Modern Insects

“…With around 1 million species described, insects are the most diverse animal lineage on Earth. The extraordinary success of insects is due, at least in part, to their long evolutionary history, as they emerged some 450 million years ago (Mya) ( Wang et al., 2016 ). This gave them enough time to evolve a series of key morpho-functional innovations that acted as drivers of expansion and diversification.…”