Mighty mite

日期:2019-03-06 04:05:02 作者:危裟 阅读:

By Hazel Muir THE false spider mite is the first animal in the history of science to make do with only one copy of its chromosomes. The discovery is overturning theories of evolution. The cells of most multicellular animals are “diploid”—they carry two copies of each chromosome. This makes evolutionary sense: if a mutation strikes a gene on one chromosome, a flawless version on the other can compensate. But no one has ever found an animal where both sexes are “haploid”—carrying a single set of unpaired chromosomes. Until now,