He proposed a grouping of arachnids with book lungs as well as pseudoscorpions, which is called "Arachnopulmonata" and is united by a shared whole genome duplication.
[7][8][9][10] He proposed that horseshoe crabs are part of Arachnida and that arachnids independently colonized land more than once,[11] using both genomes and fossils.
He previously showed that spiders recycled leg-patterning genes to make the segments of their heads, an example of an evolutionary process called cooption.
[12][13] His team later showed that a gene duplicate restricted to Arachnopulmonata is responsible for making all eye types of spiders.
[14] In 2021, his group sequenced the first Opiliones genome and created "daddy-short-legs" using gene silencing to understand how daddy-long-legs make their long legs.