In our target article, we took the position that tenure conveys many important benefits but that its original justificationfostering academic freedomis not one of them. Here we respond to various criticisms of our study as well as to proposals to remedy the current state of affairs. Undoubtedly, more research is needed to confirm and extend our findings, but the most reasonable conclusion remains the one we offeredthat the original rationale for tenure is poorly served by the current system as practiced at top-ranked colleges and universities.

Ritualized behavior, intuitively recognizable by its stereotypy, rigidity, repetition, and apparent lack of rational motivation, is found in a variety of life conditions, customs, and everyday practices: in cultural rituals, whether religious or non-religious; in many children's complicated routines; in the pathology of obsessive-compulsive disorders (OCD); in normal adults around certain stages of the life-cycle, birthing in particular. Combining evidence from evolutionary anthropology, neuropsychology and neuroimaging, we propose an explanation of ritualized behavior in terms of an evolved Precaution System geared to the detection of and reaction to inferred threats to fitness. This system, distinct from fear-systems geared to respond to manifest danger, includes a repertoire of clues for potential danger as well as a repertoire of species-typical precautions. In OCD pathology, this system does not supply a negative feedback to the appraisal of potential threats, resulting in doubts about the proper performance of precautions, and repetition of action. Also, anxiety levels focus the attention on low-level gestural units of behavior rather than on the goal-related higher-level units normally used in parsing the action-flow. Normally automatized actions are submitted to cognitive control. This swamps working memory, an effect of which is a temporary relief from intrusions but also their long-term strengthening. Normal activation of this Precaution System explains intrusions and ritual behaviors in normal adults. Gradual calibration of the system occurs through childhood rituals. Cultural mimicry of this system's normal input makes cultural rituals attention-grabbing and compelling. A number of empirical predictions follow from this synthetic model.

We argue that ritual is not a by-product as Boyer & Lienard (B&L) claim, but rather an evolved adaptation for social communication that facilitates non-agonistic social interactions among non-kin. We review the neurophysiological effects of ritual and propose neural structures and networks beyond the cortical-striato-pallidal-thalamic circuit (CSPT) likely to be implicated in ritual. The adaptationist approach to ritual offers a more parsimonious model for understanding these effects as well as the findings B&L present.

Instinct theory parsimoniously clarifies the relationships between emotions, such as fear and anxiety, and perceptions, thoughts, and actions. Its acceptance allows more elegant insights into riddles of obsessions and compulsions. Their relationship to anxiety and dysexecutive function needs to be explained, as does their characteristic egodystonia, while avoiding the pitfalls of cognitivist, empiricist, and teleological thinking.

The target article presents arguments for a motivational system dedicated exclusively to the detection of, and reaction to, particular threats to fitness, the so-called Hazard-Precaution System, which, according to the authors, drives ritualized behavior. We approach the issue of a motivational system from three perspectivesdevelopmental, psychopathological, and ethnological.

A study of the organization of obsessive-compulsive disorder (OCD) rituals in time and space illuminates a postulated mechanism on shifting focus in action parsing, from mid-ranged actions to finer movements (gestures). Performance of OCD rituals also involves high concentration rather than the automated, less attended performance of rituals in normal and stereotyped behaviors in animals and humans.

If rituals persist in part because of their memory-taxing attributes, from whence do they arise? I suggest that magical practices form the core of rituals, and that many such practices derive from learned pseudo-causal associations. Spurious associations are likely to be acquired during problem-solving under conditions of ambiguity and danger, and are often a consequence of imitative social learning.

Boyer & Lienard's (B&L's) explanation of ritualized behavior is plausible because it fits so well with elementary facts about evolution of plasticity in our behavioral repertoire. Its scope, however, may be broader than its authors explicitly admit. Science itself may be illuminated as ritual behavior. Science, like other rituals, can sustain both healthy and pathological forms.

This commentary argues against the theory that cultural ritual behavior is meaningless or that ritual action is solely a by-product of fear-based precautionary and action-parsing systems. Humans demonstrate the ability to spontaneously change their use of proximate intentions and attribute ultimate intentions to ritual actions that are not dependent upon fear or physical and emotional/mental dysfunction.

Boyer & Lienard's (B&L's) model of obsessive-compulsive disorder (OCD) rituals does not completely conform to our clinical experience with patients, and the clinical implications of their model is not described by the authors. We discuss potential differences of opinion regarding both the nature of OCD and the mechanisms involved in the maintenance of symptoms, and how emotional processing theories can account for treatment effects.

We consider evidence for ritualized behavior in the sporting domain, noting that such behavior appears commonplace both before a competitive encounter and as part of pre-performance routines. The specific times when ritualized behaviors are displayed support the supposition that they provide temporary relief from pre-competition anxiety and act as thought suppressors in the moments preceding skill execution.

There is a spectrum of child psychiatric and neurological disorders, in all of which a comorbidity with obsessive-compulsive disorder and ritualized behavior is very common. Therefore, they may appear as a basis for the rituals in children that cross into adolescence and adulthood. Resolving the nature of these disorders may help us to better understand Why ritualized behavior?

The theory of ritualized behavior should offer insight about cultural rituals. Considering ritualized behaviors' scripted actions and both the frequent absence of anxiety and the routinization of many cultural rituals, questions remain about how much and what precisely gets explained. Among religious rituals, ritualized behaviors arise more strikingly in special agent rituals, but that might be because they usually include novices.

Boyer & Lienard's (B&L's) biological model of ritual achieves a rather straightforward account of features shared by ritual pathology and the idiosyncratic rituals of children; but complexities accrue in extending it to human ritual culture generally. My commentary suggests that the ritual cultural traditions of animals such as songbirds share structural features, handicap-based origin, as well as the enabling neural mechanism of vocal learning with human ritual culture.

Responding to potential hazards is likely to require precaution-related recalibration, the extensive integration of complex variables related to inferred risk and fitness. By swamping working memory with goal-demoted actions and focusing recalibration on the inferred threat, ritualized behaviors may serve to increase the efficacy of precaution-related recalibration. This benefit may be an important mechanism maintaining non-pathological ritualized behavior.

Religionists often presuppose that mysticism aims at somehow emptying the mind. In the light of evidence, however, meditation seems rather to consist of ritualized action without an explicit emphasis on subjective experience. Boyer & Lienard's (B&L's) theory of ritualized action as swamping working memory thus might help explain the effects of meditation without postulating experiential goals the mystics obviously do not have.

Tourette Syndrome (TS) and Obsessive-Compulsive Disorder (OCD) are highly associated and often it is difficult to differentiate their symptomatology. In TS, habit forming neuronal systems may form habits of their ownsometimes similar to ritualized behavior. However, whereas in OCD merely the affect-loop is touched, in TS the sensorimotor-loop plays the major role, although some overlap can be seen in the clinical spectrum between TS and OCD. The latter is mainly related to the just-right phenomenon which shows a clear developmental course. An analogous behavioral model for TS and OCD with reference to just-right is suggested.

Humans are, by design, imperfect experimentalists. The cost of testing each step of a process exceeds the benefit of knowing which steps can be eliminated. To an outsider who knows which steps are superfluous, the actors appear superstitious, even ridiculous. Nonetheless, the exact duplication of all steps is rational for the imperfect experimentalist. The case of ritual in autism illustrates this point.

Numerous sex differences in obsessive-compulsive disorder (OCD) instantiations are likely universal, as the associated evolutionary threats and concerns onto which they map were differentially important to the two sexes. Hence, although some ritualized behaviors or thoughts are indeed culture-specific, others are both culturally and temporally invariant as they are rooted in universal Darwinian etiologies (e.g., the sex differences in OCD symptomatology posited here).

We suggest that morbid jealousy falls on the extreme end of a jealousy continuum. Thus, many features associated with normal jealousy will be present in individuals diagnosed with morbid jealousy. We apply Boyer & Lienard's (B&L's) prediction one (P1; target article, sect. 7.1) to morbid jealousy, suggesting that fitness-related life-cycle dimensions predict sensitivity to cues, and frequency, intensity, and content of intrusive thoughts of partner infidelity.