Thermococcales, a group of organisms that thrive in extreme heat, have a diverse genetic makeup that helps them survive in harsh environments. By studying 30 species, scientists found over 6000 gene families that evolve as more genomes are added. These organisms have specific genes for dealing with heat stress, like HSP20 and HSP60, which have evolved slowly over time. Different genes related to enzymes, movement, and defense mechanisms also evolve at different rates, possibly to adapt to their unique habitats. This research sheds light on how Thermococcales adapt and diversify, providing insights into early life forms' metabolic traits.