Analysis of Positive Selection Provides Insights into Lifestyle- and Lineage-Specific Patterns of Molecular Evolution in Insects

Abstract

Insects are among the most divergent and most rapidly evolving species, which allow them to adapt to virtually all ecosystems. Successful adaptation requires overcome of challenging environmental conditions. The best-known molecular mechanism underlying successful adaptation is positive selection. This mechanism favors in species by gaining new beneficial mutations and transferring these beneficial mutations to new generations in populations via reproduction. In this study, a total of 12 insect species belonging to 6 orders and two morphogenesis groups were used to investigate positive adaptive selection in insects and their common ancestors using a total of 535 one-to-one single-copy ortholog genes. The highest number of the positively selected gene was found in Onthaphagus taurus and Dendroctanus ponderosae, and the lowest number of positively selected genes were found in a homopteran species, Acyrthosiphon pisum. The highest number of positively selected genes was detected in the common ancestor of the orders Lepidoptera and Diptera, followed by the node that separated Hymenoptera from a recent common ancestor of the orders Homoptera and Isoptera. Genes involved in the fundamental biological process digestion, oxidative reduction, transcription, and translation were among the core positively selected genes. Lifestyle and lineage-specific genes were found to be under positive selection.

Keywords

• insects
• genome
• molecular evolution
• böcekler
• genom
• moleküler evrim