An animal defending against a predator may engage in either " fight or flight " or " tend and befriend " in response to predator attack or threat of attack, depending on its estimate of the predator's strength relative to its own. Alternative defenses include a range of antipredator adaptations , including alarm signals . An example of an alarm signal is nerol, a chemical which is found in the mandibular glands of Trigona fulviventris individuals.  Release of nerol by T. fulviventris individuals in the nest has been shown to decrease the number of individuals leaving the nest by fifty percent, as well as increasing aggressive behaviors like biting.  Alarm signals like nerol can also act as attraction signals; in T. fulviventris, individuals that have been captured by a predator may release nerol to attract nestmates, who will proceed to attack or bite the predator. 
Tribulus works by stimulating the anterior pituitary to produce Leutinizing Hormone. Tribulus is a first choice addition to many testosterone boosting formulas because it could keep natural levels testosterone not having any negative effects on its long term production. It is a well-documented risk to introduce exogenous hormonal substances (like steroids) that shut down the endogenous production of testosterone. As the use of these products tapers down, it is essential that the endogenous production kicks back in as soon as possible because normal levels of these hormones are needed to maintain much of the gains made while taking them., therefore tribulus becomes a valuable addition to any hormone boosting stack.