// Definition
The two-spotted spider mite (Tetranychus urticae) possesses the smallest known arthropod genome (~90 megabase pairs) yet has evolved extraordinary adaptability including 1,000+ host plant species and the ability to manipulate plant defense signaling pathways.
// From the Episode
Despite having far fewer genes than cannabis (900 Mb) or humans (3.1 Gb), spider mites can quickly develop resistance to plant toxins and defense mechanisms. Rust mites (Aculops genus) have even smaller genomes at ~32 Mb. Research shows mites can cause plants to mount the wrong defense response, which they then exploit. Selection pressure from heavy chemical use (especially in China) has created populations resistant even to noxious compounds like DDT.