Bald-faced hornet viable brood in the comb fragment. The physical nature of cues mediating natal comb recognition is unknown, though some researchers propose distinct cuticular hydrocarbon profiles allow wasps to recognize nest mates. "D. maculata" is characterized by low paternity, worker reproduction and queen-worker conflict. Divergent genetic interests between workers and their queen cause intra-nest struggle for control, which disrupts social organization. Because of haplodiploidy, workers are unable to mate. However, their unfertilized eggs become males. Workers and their queens are most related to their own sons. Natural selection will therefore favor those workers who produce their own sons rather than rearing
Robert Bald of the system of apprenticeship in the West Indies. The meeting attendees included the Lord Provost and other city dignitaries, as well as those connected with the Emancipation Society. Bald is reported as seconding the first resolution against the evils of apprenticeship, which was called for the abolition of a system that was but slavery under another name. In 1808 Bald mentored Francis Benjamin Hall, civil engineer and later acted as a mentor for the teenaged James Nasmyth, engineer and inventor of the steam hammer, introducing him to noted engineers and taking him on trips to engineering sites. Nasmyth mentions