Mites And Ticks Turn Out To Be Close Relatives

Lately, the scientists from the University of Bristol and the Natural History Museum in London have reframed the evolutionary history of the chelicerates. Chelicerates are a mega-diverse group of around 110,000 arthropods that consist of spiders, scorpions, mites and ticks. The genomic evidence showed that mites and ticks do not constitute two distantly related lineages.

They belong to the same evolutionary line. This feature makes them, one of the most diverse groups amongst the chelicerates alongside giving a whole new perspective to their biodiversity. A major part of the biodiversity consists of the Arthropoda or jointed-legged animals.  They together pollinate (bees) and destroy crops (locusts), are major food sources (shrimps and crabs), and are also vectors of serious diseases such as malaria and Lyme disease (mosquitoes and ticks). Fossils evidence that arthropods are ancient and have been in existence for over 500 million years now. The secret hidden behind their evolutionary success is reflective of their outstanding species diversity. In order to understand the success of the arthropods, it is essential to understand how the different arthropod lineages relate to each other. Dr Greg Edgecombe of the Natural History Museum London believes that: "Because of their anatomical similarities it has long been found that mites and ticks together form a natural evolutionary group, which has been named Acari. However, all anatomists do not agree to this proposition, and genomic data could not trace any support for this idea before. The lead author, Dr. Jesus Lozano Fernandez, from Bristol's School of Biological Sciences, stated that spiders are terrestrial animals of iconic nature that have persistently been a part of human imagination and folklore. It reflects mythological and cultural symbols, as well as more often being sources of inner fears or admiration. In order to come up with their findings, the researchers made use of an almost even representation of mites and ticks, which is the most complete species-level sampling at the genomic level for these groups till date. The genealogical tree can presently be used as the foundation for studies with the help of comparative genomics so as to resolve the problems of potential biomedical and agricultural importance, for example, the identification of the genomic changes that underpinned the evolution of blood-feeding parasitic ticks from ancestors that were not blood-feeders."

By: Anuja Arora

Content: https://www.sciencedaily.com/releases/2019/05/190524081637.htm