Queen primer pheromones of S. invicta, a focus of much attention in LI08, have been shown to attract workers to tend reproductive queens, prevent reproduction by alate queens in the nest, inhibit sexualization of female larvae, and, in monogyne colonies, mediate worker imprinting on the mother queen and execution of supernumerary reproductives [reviewed in 4].
In addition, he said, the females will be sterile to prevent reproduction.
Biologists may appreciate this: the weirdest biological finding that I ran across is a study showing that sodium tungstate prevents reproduction in the earthworm species, Eisenia fetida (doi 10.1897/04-578R.1).
The salmon are also made sterile to prevent reproduction in the event they do escape, although the sterilization technique is not foolproof.
(Hot news from the Vatican: the use of condoms may be permissible to prevent HIV infection, so long as the intention is not to prevent reproduction!) I do have reservations about going to China, not because the relevant cells are derived from aborted foetuses, but because we don't yet know how good the procedure is.
Once identified, the scientists tested the potential pheromones on isolated workers to see if they prevented reproduction.
Both cycles are controlled by the endocrine system and the normal hormonal changes that occur can be interfered with using hormonal contraception to prevent reproduction.
Postelsia is a protected species, however, and harvesting it is illegal throughout much of its range, as clipping the blades too low, below the meristem, prevents reproduction.
The high workload (300 microscopy slides per day) by a single technician with brief microscopic examination of small volumes of CSF in a 'real world' setting prevents reproduction of yields seen in a research setting [40].
