THE EVOLUTION OF ALTERNATIVE GENETIC SYSTEMS IN INSECTS

摘要: There are three major classes of insect genetic systems: those with diploid males (diplodiploidy), effectively haploid (haplodiploidy), and without (thelytoky). Mixed systems, involving cyclic or facultative switching between thelytoky either the other also occur. I present a classification systems insects estimate number evolutionary transitions them that have occurred. Obligate has arisen from each there is evidence over 900 such origins The reversions obligate to difficult estimate. few in number: five thelytoky, eight haplodiploidy (including paternal genome elimination), strange case Micromalthus, two diplodiploidy scale insects. Available tends support W.D. Hamilton's hypothesis maternally transmitted endosymbionts been involved haplodiploidy. Bizarre extrazygotic inheritance Sternorrhyncha not easily accommodated into any existing systems.