Thus, females switched gradually from minor worker ants to media and major sub-castes during their development, corresponding to their increase in body size and chelicerae size.
The identities of many valid names are in question in Madagascar because insufficient geographic and morphological information was provided in their original descriptions, or type specimens are of uninformative minor worker castes or are damaged.
Although HSGE is conducted on pooled material (multiple individuals from single colonies) for some applications, the method is sufficiently sensitive to be used on individual adult queen heads and all but the smallest adult minor worker thoraces+heads [12], [36] (Fig. 1).
We determined levels of expression for given genes by analyzing RNA-seq data from the three castes which also have DNA methylation and ChIP-seq data (male, minor worker, major worker; Bonasio et al. 2010).
In the ant hierarchy, they are minor workers, a colony's expendables.
This possibility was in fact first raised by Currie et al. when trying to explain the observation that minor workers (specialized in tending the garden) had a lower abundance of actinomycetes on their cuticles as compared with major workers.
"We have provided a biological mechanism that can explain that difference" between major and minor workers, Alvarado says.
"We have provided a biological mechanism that can explain that difference" between major and minor workers, says Sebastian Alvarado, lead author on the paper, who is now at Stanford University in Palo Alto, California.
Most of the populations of Pheidole ants have ruling queens, small but busy "minor" workers, and brawny "major" workers, also called soldiers.
But he said more experiments were needed to test the theory, because while minor workers have smaller heads than the majors, they still have barbed spines.
