Sexual conflict between two species can push back an evolutionary “ sleeping accommodation battle purple , ” leading to some crazy adaptations . Harvester ant queens steal sperm away from males of another mintage during sex — without even producing fertile young . Thework , published inProceedings of the Royal Society Bthis week , is a rare example of reproductive conflicts - of - interest between males and females of unlike species .
In the southwesterly U.S. , mating between queens and males fromPogonomyrmex barbatusandPogonomyrmex rugosusresult in unfertile cross . These go on to become worker in the poove ’ colonies , but they ’re evolutionary numb ends for the males . Daughter queen are only produced with spermatozoon from Male of her own species . To try if hybridization can drive sexually antipathetical coevolution , a University of Vermont duet observed conjugation between the two reaper ant coinage in the desert near the border between Arizona and New Mexico . They found that both sexes manipulate their “ copulatory investiture ” to puzzle out against each other .
Once a year in the summer , a day or two after a impenetrable monsoon rainstorm , harvester pismire have a crazed , barren - for - all conjugation horde . The male ca n’t distinguish queens of their own species from queens of another … at least not until they ’ve already started copulating . Once he realizes his misapprehension , he lowers his spermatozoon transfer rate to continue some for a better investing later on on .
But the queens have germinate a counter - version . “ They lock slow Male in copula importantly longer , until they finally deliver the same amount of sperm that they normally would have,”UVM ’s Sara Helms Cahansays in anews release . “ Essentially , they are sperm sponge . ”
In that jumbal of ants depict above , the behemoth ( mostly reddened ) queen and the male person she ’s checkmate with on the right are locked in place by their coital organ . Even if he lets go altogether , he ’d still be steadfastly attached to her . Back in the research laboratory , the team found no dispute in the total quantity of sperm transferred between same - coinage and inter - specific pairs .
These determination are an example of a larger biological phenomenon called the Red Queen Hypothesis . InThrough the Looking Glass , theRed Queen tell : “ Now , here , you see , it take all the track you’re able to do , to keep in the same position . ” Every organism ’s competitors , predator , and parasites are always evolving , so everyone ask to germinate as tight as potential just to keep up .
“ In this harvester ant scheme there really necessitate to be some sorting of stalemate , ” study authorMichael Herrmann of UVMsays , “ because if the males actually were able to order what type of female they were mat with , they would cut off off the sperm to the queens that require it . ” These queens must mate with both species of males : They ca n’t produce workers with sperm cell from males of their own species . To foreclose an entire system prostration , neither queens nor male should have too many evolutionary reward .
effigy : Sara Helms Cahan ( top ) , Joshua Brown ( mediate )
