This stability exists despite the incredible diversity in wing patterns, sizes, and caterpillar morphology across more than 160,000 species worldwide today, according to one study. new paper It was published in the magazine natural ecology and evolution.
Butterflies and moths (in order) Lepidoptera) make up 10% of all described animal species and are extremely important pollinators and herbivores in many ecosystems.
In a new study, Professor Mark Blaxter and colleagues from the Wellcome Sanger Institute set out to understand the processes driving the evolution of chromosomes in this highly diverse group.
They analyzed and compared more than 200 high-quality chromosome-level genomes of butterflies and moths.
They identified 32 ancestral chromosomal components; Merian element Thanks to the work of pioneering 17th century entomologist Maria Sibylla Merian, most butterfly and moth species have remained intact since their last common ancestor more than 250 million years ago.
With the exception of a single ancient fusion event between two chromosomes that led to the 31 chromosomes found in most species today, the chromosomes of most modern species correspond directly to these ancestral Merian elements.
Researchers discovered that not only are chromosomes incredibly stable, but the order of genes within them is also stable.
They discovered several species with small changes, mainly involving the fusion of small autosomes and sex chromosomes. This highlights the role of chromosome length as a driver of evolutionary change.
However, scientists believe that the blue butterfly (lissandra) and the group containing cabbage butterflies (Pieris) ignored these genomic structure constraints.
These groups underwent large-scale chromosomal reshuffling, including large-scale chromosome reshuffling through chromosome breakage and fission and fusion.
This study improves our understanding of the factors that lead to genetic diversity in these insects. This will guide efforts to protect and conserve specific species facing unique challenges and environmental changes related to climate change.
“The chromosomes of most butterflies and moths living today can be directly traced back to 32 ancestral Merian elements that existed 250 million years ago,” said Dr. Charlotte Wright, researcher at the Wellcome Sanger Institute. said.
“It is surprising that even though the species has diversified extensively, its chromosomes have remained surprisingly intact.”
“This calls into question the idea that stable chromosomes may limit species diversification. Indeed, this feature may be the basis for building diversity. We We hope to find clues about rare groups that have circumvented these rules.”
“Studies like this that allow us to delve into these evolutionary processes are only possible through efforts like the Darwin Tree of Life Project, which generate high-quality, publicly available genome assemblies,” Blaxter said. the professor said.
“We are stepping up these efforts with Project Psyche, where we aim to sequence all 11,000 butterfly and moth species in Europe in collaboration with collaborators across the continent.”
“As important pollinators, herbivores, and food sources in a variety of ecosystems, and as powerful indicators of ecosystem health, a deeper understanding of the biology of butterflies and moths through Project Psyche will This will be useful for future research on adaptation and speciation for biodiversity conservation.”
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CJ light other. Comparative genomics reveals the dynamics of chromosome evolution in Lepidoptera. Nat Ecole Evol, published online on February 21, 2024. doi: 10.1038/s41559-024-02329-4
Source: www.sci.news
