Charisma as signal: An evolutionary perspective on charismatic leadership

We present an evolutionary perspective on charismatic leadership, arguing that charisma has evolved as a credible signal of a person's ability to solve a coordination challenge requiring urgent collective action from group members. We suggest that a better understanding of charisma's evolutionary and biological origins and functions can provide a broader perspective in which to situate current debates surrounding the utility and validity of charismatic leadership as a construct in the social sciences. We outline several key challenges which have shaped our followership psychology, and argue that the benefits of successful coordination in ancestral environments has led to the evolution of context-dependent psychological mechanisms which are especially attuned to cues and signals of outstanding personal leadership qualities. We elaborate on several implications of this signaling hypothesis of charismatic leadership, including opportunities for deception (dishonest signaling) and for large-scale coordination.     

The age of exploration and exploitation: Younger-looking leaders endorsed for change and older-looking leaders endorsed for stability

The current contribution extends theorizing on leadership and the exploration–exploitation dilemma using an evolutionary perspective. A theoretical connection is made between the exploration–exploitation dilemma and age-biased leadership preferences for exploratory change versus stable exploitation. For the majority of human evolution our species was semi- or entirely nomadic and the trade-off between exploration versus exploitation had substantial physical- and experience-based requirements which align with leadership opportunities as moderated by age. Thus, given the consistency and importance of correctly assigning leadership for the exploration–exploitation dilemma, human evolution has likely selected for age-biased leadership endorsement. Across three experiments we find that younger-looking leaders are endorsed for times of exploratory change and older-looking leaders for stable exploitation. Further, our results indicated that older leaders are endorsed for leading conservative exploitation of nonrenewable resources and younger leaders for exploration of renewable alternatives (i.e., green leadership). The results introduce an age-biased leadership endorsement hypothesis.     

Ultrasonometric profiling of incidence and risk of osteoporosis in rural women

BACKGROUND: It is estimated that over 200 million people worldwide have osteoporosis. The prevalence of osteoporosis is continuing to escalate with the increasingly aging population. The major complication of osteoporosis is an increase in fragility fractures leading to morbidity, mortality, and decreased quality of life. This investigation profiled the incidence and risk of osteoporosis in adult women from a rural setting using ultrasonic bone scanning technology. METHODS: Between 2001 and 2005, adult female subjects (n = 323) in the age range of 40-87 were drawn from an independent, community dwelling, convenience sample. Bone mineral density T-scores were evaluated using heel ultrasonometry. Demographic and risk factor data, Merck Osteoporosis Evaluation SCORE questionnaire data, and the Osteoporosis Risk Assessment questionnaire data were analyzed. RESULTS: Results of these scans indicate that 25% of the total population had a T-score < or = -1.0, implying a 1.5- to 2.0-fold increase in risk ratio of hip or spinal fracture for each standard deviational decrease. Age at menopause and weight had a positive correlation with T-scores. While the overall scores on the Merck SCORE questionnaire were inversely correlated to T-scores, no significant correlation was found between the Osteoporosis Risk Assessment questionnaire and T-score data. Additionally, women who had taken estrogen had significantly higher T-scores (p = 0.038) than those who had not. CONCLUSION: That approximately 25% of this sample has low bone mass or osteoporosis underscores the importance of early screening in order to develop preventative awareness and provide education on bone health management. This finding has particularly important ramifications, since the sample was rural women, who typically have limited access to diagnostic bone density procedures.     

Facing the situation: Testing a biosocial contingency model of leadership in intergroup relations using masculine and feminine faces

Using an evolutionary psychology framework we propose that leadership and followership are evolved traits to solve recurrent group coordination problems. We argue that adaptive problems such as those concerning intergroup conflict or cooperation activate different cognitive leadership prototypes, and the face conveys diagnostic information about the suitability and emergence of intergroup leadership. Consistent with hypotheses we find that followers expect masculine-faced leaders to behave competitively and feminine-faced leaders cooperatively in intergroup relations. Furthermore, individuals prefer leaders whose facial cues match the adaptive problem. For example, a masculine-looking leader is preferred in a competitive intergroup setting. Also, this match between face and situation is reinforced with a consistent leadership message such as a masculine-looking leader expressing the need for competition. An evolutionary perspective provides a deeper understanding of the biological aspects of leadership and generates many novel hypotheses about how markers such as the human face affect leadership emergence and effectiveness.