Male Crazy ants’ (an invasive species) are chimeras with strange genomes: A biological first and a new mode of reproduction

Names have meaning! 

"... But there’s another reason to call these invasive ants crazy: males of the species are a mixture of two warring cell lineages, researchers report in a study ... Other creatures sometimes form such chimaeras — usually a developmental accident — but yellow crazy ants are the first known animal for which this property is an essential aspect of life. ..."

From the abstract of the perspective:

"Species with unusual modes of reproduction are overrepresented among invasive organisms that are dispersed by humans across the globe and can wreak havoc wherever they land. Invasive species thrive in disturbed habitats as well as island ecosystems, which have evolved largely in isolation and are therefore particularly vulnerable. However, upon arrival, colonizers face their own challenges: At initially tiny numbers, finding mates can be almost impossible, and inbreeding and genetic bottlenecks can be severe. Successful invaders often overcome these challenges through ingenious innovations in their reproductive biology. ...  show that the yellow crazy ant (Anoplolepis gracilipes), an invasive species that has spread across Asia and the western Pacific, features workers that are hybrids between two separate genetic lineages, and males that are genetic chimeras of the same two genetic stocks."

"A new mode of reproduction in animals

Multicellular organisms typically develop from a single cell into a collection of cells that all have the same genetic material. Darras et al. discovered a deviation from this developmental hallmark in the yellow crazy ant, Anoplolepis gracilipes. Males of this species are all chimeras, a collection of haploid cells with only maternal or paternal genetic material ... These chimeras develop from fertilized eggs in which parental nuclei divide independently. Genetic analyses show that this unusual mode of reproduction is probably the result of a genetic conflict between two co-occurring lineages. ...
This showed that each male cell contained just one version of the ant’s genome. But this genome differed between cells. Some harboured a lineage present in queens, and defined by an ‘R’ chromosome, whereas other cells carried a lone copy of a different genome, with a ‘W’ chromosome. ..."

From the abstract:

"Multicellular organisms typically develop from a single fertilized egg and therefore consist of clonal cells. We report an extraordinary reproductive system in the yellow crazy ant. Males are chimeras of haploid cells from two divergent lineages: R and W. R cells are overrepresented in the males’ somatic tissues, whereas W cells are overrepresented in their sperm. Chimerism occurs when parental nuclei bypass syngamy and divide separately within the same egg. When syngamy takes place, the diploid offspring either develops into a queen when the oocyte is fertilized by an R sperm or into a worker when fertilized by a W sperm. This study reveals a mode of reproduction that may be associated with a conflict between lineages to preferentially enter the germ line."

Crazy ants’ strange genomes are a biological first Males of the notorious yellow crazy ant carry a mixture of genomes, a phenomenon unseen in other animals.

The unusual genetics of invasive ants (perspective, no public access) The males of an invasive ant species are chimeras of two distinct genetic lineages

Obligate chimerism in male yellow crazy ants (no public access)