The chromosomes of butterflies and moths have remained virtually unchanged over the last 250 million years, despite the great diversity of shapes, colors, and flight patterns.
The revelation comes from a study published in the journal Nature Ecology & Evolution, in which researchers compared more than 200 lepidopteran genomes to deepen knowledge about their evolutionary history.
The order Lepidoptera, which today includes more than 160,000 known species worldwide, accounts for about 10% of all described animal species, 11,000 of which occur in Europe. Like other insects, they are important pollinators and herbivores, helping to maintain the health and proper functioning of ecosystems.
During the genomic analysis, the researchers identified 32 ancestral chromosomes, nicknamed ‘Merian elements’, which they say have remained intact in almost all species of butterflies and moths since they diverged from their common ancestor more than 250 million years ago and which are the ‘genetic cornerstones’ of Lepidoptera.
“The chromosomes of most of the butterflies and moths that exist today can be traced directly back to the 32 Merian ancestral elements that were present 250 million years ago,” explains Charlotte Wright, a researcher at the Wellcome Sanger Institute and the first author of the article, in a statement.
The scientists admit that, despite the lepidopterans showing a great diversity, “their chromosomes have remained remarkably intact,” noting that this “challenges the idea that stable chromosomes can limit the diversification of species.”
The researchers believe that the results of this study will help “inform and improve conservation efforts,” taking into account the genetic information of these insects, as well as their adaptation to the effects of climate change.
