ENTREPRENEURS AND EVOLUTIONARY BIOLOGY: THE RELATIONSHIP BETWEEN TESTOSTERONE AND NEW VENTURE CREATION 

Roderick E. White, The University of Western Ontario
Stewart Thornhill, The University of Western Ontario
Elizabeth Hampson, The University of Western Ontario 

CHAPTER MENU 

ABSTRACT
INTRODUCTION
BIOLOGY AND BEHAVIOR
TESTOSTERONE RESEARCH
T & E RELATED BEHAVIORS
CONCEPTUAL MODEL & HYPOTHESES
ANALYSIS AND RESULTS
DISCUSSION
ACKNOWLEDGMENTS
CONTACT
REFERENCES
FIGURE 1
FIGURE 2
TABLE 1
TABLE 2
TABLE 3 

ABSTRACT 

Attempts to discover individual differences related to entrepreneurial behavior have had limited success and even less acceptance amongst management scholars. Taking a different approach this study explores the relationship between a heritable biological characteristic of the individual, testosterone level, and prior entrepreneurial experience. Such a relationship is consistent with evolutionary psychological theory. The evidence from this study supports the theory. As hypothesized, higher testosterone levels are associated with prior new venture start-up experience, both directly and mediated by psychological disposition towards risk. 

INTRODUCTION 

This paper explores the specific relationship between an evolved biological trait, testosterone level, and entrepreneurial behavior. It was originally motivated by the observation that many of the behaviors researchers in the neurosciences, endocrinology and psychology have associated with higher testosterone levels are similar, if not identical to behaviors management researchers have related to entrepreneurship. But we quickly came to realize this question is part of a much larger debate and raises a bigger question: Are business-related behavior learned, or can they, at least in part be explained by our biology? Most management research makes the former assumption, and implicitly rejects the latter. It is assumed the human mind is basically a blank slate, a general-purpose computer programmed by our parents, our schools and our culture. This bias towards learned behaviors is pervasive. It so permeates sociology and psychology and has been labeled the “Standard Social Science Model” (Tooby & Cosmides, 1992; Markoczy & Goldberg, 1998). This research explores the other possibility; that our evolved biology influences business related behavior; specifically if an individual’s testosterone is related to significant involvement in a new venture. 

There is a history of studying the relationship between individual traits and entrepreneurship. However, this type of research had fallen into disfavor with many scholars concluding “that efforts to study entrepreneurs—their characteristics, their behavior, their skills, or their aptitudes—constituted a dead-end strategy which would ultimately add little to our understanding” (Baron, 2002: 227). Even so it is hard to accept that individual differences do not affect the manifestation of entrepreneurial behaviors. Indeed contemporary definitions of the entrepreneurship domain prominently feature the individual. Shane and Venkatraman describe entrepreneurship as “the nexus of two phenomena: the presence of lucrative opportunities and the presence of enterprising individuals” (2000: 218) (Shane & Venkatraman, 2000). This definition has an environmental or contextual component (opportunities) and an individual component (the entrepreneur). Entrepreneurship occurs at the conjunction of the opportunity and the individual. It is individuals who pursue and exploit new business opportunities. Not all environments are equal in opportunities and not all individuals are equally likely to recognize and pursue those opportunities. What individual factors make a difference to entrepreneurial behavior and why they matter are the subject of much debate. But most scholars believe individuals and individual differences do matter. The entrepreneur is a key component of entrepreneurship. 

This paper reviews testosterone and entrepreneurship literatures and identifies certain behavioural similarities. By themselves similarities do not provide a theory for why testosterone evokes behaviors conducive to entrepreneurship. Evolutionary psychology is the theory used to make this ultimate link (Cosmides & Tooby, 1997). After developing the relationship between testosterone and certain entrepreneurial behaviors and proposing a basic causal model the method used to explore this relationship is described. Findings and implications are discussed. 

BIOLOGY AND BEHAVIOR 

When thinking about biology and behavior it is helpful to make a distinction between proximate causes or factors and ultimate factors. Increasingly it is accepted that our physiology, including brain structure and processes, directly affect our daily behavior (Buss, 1997; Thornhill, Tooby, & Cosmides, 1997; Buss, 1999). These physiological factors are proximate to the behavior. The evolutionary factors that produce a given genome and the accompanying physiology are called the ultimate (or distal) factors. 

Genes are the biological mechanism by which traits are passed from generation to generation, but it is behaviors (not genes, or even physiological factors) that are selected for. Genes are not directly connected to, nor do they determine our daily behaviors. Genes result in a physiology that facilitates certain behaviors and those behaviors with a survival and reproductive advantage increase the frequency of their associated genes in subsequent generations, and spread throughout the population. But genes do not determine behavior in any specific way. Genes express themselves in our physiology, including our endocrinology. These proximate biological characteristics influence behavior. It is through this indirect process linking ultimate and proximate factors that biological evolution results in some correspondence between genes and behavior. 

Genes establish the potential for each individual’s biology but they do not dictate it. Developing the height and endurance to play in the NBA requires not only the genetic potential but also adequate nutrition, physical conditioning and learned skills. There is also a rich interaction between our endocrinology, other aspects of our physiology and the social environment. Biology only creates a predisposition or potential for certain behaviors; it does not fully determine complex behaviors. Learning explains much about complex social behaviors. That learning may be part of a formal educational process or less formal socialization processes. But biology still plays a role. It interacts in significant and interesting ways with these learning processes. Biosocial theory and research is just beginning to explore these rich interactions (Udry, 2000; Booth, Johnson, Granger, Crouter, & McHale, 2003). 

TESTOSTERONE RESEARCH 

Testosterone (T) is an androgen produced in the testes (in men), in lesser amounts in the ovaries (of women) and the adrenal gland (in men and women). It peaks in late adolescent for young adult males and than declines with age. It has a regular daily and seasonal variation (Dabbs, 1990). An individual’s production rate of T is over 80% heritable (Meikle, Stringham, Bishop, & West, 1988). T levels can affect both obvious physiological characteristics (e.g. muscle development) and subtle physiological attributes (e.g. brain development, structure and processes) that may in turn affect psychology. T can affect our psychology not only by influencing brain structure during early development, but also by directly or indirectly activating receptors present in the adult brain it can subtly affect ongoing neural processes. The effect of T upon specific neural mechanisms and how this influences behavior is only just being explored. However at a more general level T is one of the most studied hormones (Mazur & Booth, 1998a; Mazur & Booth, 1998b; Dabbs, 2000). 

Testosterone production is a proximate biological factor influencing behavior. But understanding why it is encoded in our genes requires a distal or evolutionary explanation. From an evolutionary perspective testosterone is primarily about dominance (Mazur et al., 1998b) and dominance is about hierarchy and social structure (Pierce & White, 1999). A dominance hierarchy occurs when members of a social group yield control over valued, non-plentiful resources to another member of that group, and is the relative ordering or ranking of members by their resource prerogatives (Mazur, 1985; Fiske, 1991; Ellis, 1993). In our ancestral environment the member or members of a social group with privileged access to resources (food, water, mating privileges, assisted child rearing, etc.) had a reproductive advantage over their conspecifics. Their relative gene frequency would increase in the next generation. 

The evolutionary social psychologists Leda Cosmides and John Tooby have noted that “our ancestors have been members of social groups and engaged in social interaction for millions and probably tens of millions of years.” (Cosmides & Tooby, 1992: 163) They conclude that in the same way evolution affects physical characteristics it also moulds psychological abilities into a collection of specialized psychological mechanisms “organized to collectively guide thought and behavior with respect to the evolutionarily recurrent adaptive problems posed by the social world.” (1992: 163). Testosterone is associated with the physiological characteristics: strength and size, and psychological tendencies: aggressiveness, risk-taking and persistence that led to dominance in the social hierarchies of our Pliocene forbearers.  

In our long ago ancestral environment an aspiring male entered into a dominance contest by challenging the incumbent alpha male of his group. Threat, bluff and overt aggression would ensue with all the attendant risks of injury or death for both parties (Wrangham & Peterson, 1996). Seeking dominance required initiative, assertiveness and taking risks but winning the dominance contest yielded the prerogatives of the alpha position. As a result of cultural and perhaps biological evolution (Sober & Wilson, 1998; Richerson & Boyd, 1998; Richerson & Boyd, 1999; Boehm, 2000a; Boehm, 2000b) aggressive dominance behaviors became unacceptable in most contemporary societies. But that does not mean status seeking behaviors have disappeared, or testosterone no longer affects those behaviors. Evolution rarely completely discards anything. Rather those T-induced behaviors are often channeled into more prosocial avenues. Successful individuals direct their dominance seeking (and risk-taking) propensities to other endeavors, like business, and elevate their status in socially acceptable ways (Frank, 1999). 

T & E RELATED BEHAVIORS 

Having established a general theoretical argument linking T and dominance we will examine the literature linking T with specific types of behavior or psychological traits. These are behaviors and traits with the potential to enhance social status, at least in our ancestral environment, and perhaps in contemporary business settings. The literature review will focus upon T related behaviors of possible consequence in business situations. Subsequently the business literature will be reviewed to identify similar behaviors associated with entrepreneurship. 

T Related Behavior 

More benign prosocial forms of aggressiveness: assertive, take-charge behaviors are associated with T. Dabbs, Bernieri, Strong, Campo and Mulun found student subjects with higher basal levels of T engaged social situations more quickly, were more focused, had a direct expressive style and “displayed more forward and independent manner.” (Dabbs, Bernieri, Strong, Campo, & Milun, 2001: 27). Within sex results were similar for both men and women. These findings are consistent with other research finding high T individuals to be more independent, (Strong & Dabbs, 2000) restless and action oriented (Dabbs, Strong, & Milun, 1997). High T college students, both male and female are on average more self-centered (versus other-centered) (Dabbs, Hopper, & Jurkovic, 1990; Harris, Rushton, Hampson, & Jackson, 1996). Similarly, high T individuals are less likely to smile and show deference (Cashdan, 1995; Dabbs, 1997). 

Words used to describe the behaviors (or traits) associated with high T include: assertive, engaged, focused, expressive, independent, action-oriented, restless, self-centered, non-deferential, persistent and fearless. T is common to all these behaviors and as would be expected this cluster makes a reasonably consistent set. Individuals with one of these attributes often exhibit others. But are these behaviors consistent with entrepreneurship? The literature identifying behaviors and traits associated with entrepreneurship (E) is reviewed in the next section. 

E Related Behavior 

Before reviewing the behaviors associated with entrepreneurship some definition of the term is required. E is not like T. T is a molecule. It has a physical presence; T’s absence or level can be assessed by objective testing procedures. The same cannot be said of entrepreneurship. Its meaning and definition are socially constructed. Accepting that entrepreneurship occurs at the conjunction of opportunities and individuals (Shane et al., 2000), what behavior(s) makes one an entrepreneur? Many behaviors have been suggested but clearly the act of founding a new business venture qualifies (Gartner, 1994; Stewart, Carland, & Carland, 1996; Miner, 2000). This straightforward, and easily observable entrepreneurial behavior, was sufficient for this study. 

Research on the traits of entrepreneurs has waxed and waned over time and results have been mixed (Hull, Bosley, & Udell, 1980; Baron, 2002). But the belief that certain individuals will seize an opportunity, while others in the same circumstance will not, is compelling. The corollary, that observable individual differences can explain some of the variance in entrepreneurial behavior has continued to motivate research. This research provides clues as to entrepreneurial traits. 

One of the first personality attributes to be linked to entrepreneurial activity was need for achievement (McClelland, 1961; McClelland, 1965; Hornaday & Aboud, 1971; Begley & Boyd, 1986). Johnson (1990) reported a positive relationship between entrepreneurial behavior and achievement motivation in his review of 23 studies dating back to McClelland’s original work (Johnson, 1990). Miner (2000) found that personality characteristics, including a measure for personal achievement, were effective predictors of new business founding. 

Recent studies have extended the list of entrepreneurial traits to include a proactive personality disposition. Individuals with proactive personalities “scan for opportunities, show initiative, take action, and persevere” (Bateman & Crant, 1993: 105). They can be described as action-oriented, high energy individuals. Crant (1995) established a positive association between proactivity and entrepreneurial intentions (Crant, 1995) and Bercherer and Maurer (1999) make the link with actual new venture creation (Bercherer & Maurer, 1999). Persistence and perseverance have also been identified as attributes of entrepreneurs (Kets de Vries, 1985; Hatch & Zweig, 2000). Several studies suggest entrepreneurs feel they can control business outcomes (Robinson, Stimpson, Huefner, & Hunt, 1991). Internal locus of control was one of the factors Wooten, Timmerman and Folger (1999) used to predict self-employment (Wooten, Timmerman, & Folger, 1999). 

The popular view of entrepreneurs as risk-takers is controversial (Brockhaus, 1980; Low & MacMillan, 1988). Busenitz (1999) suggests entrepreneurs may simply perceive situations differently; using psychological processes, biases and heuristics which lessen their perception of risk in a given situation. Whatever their perceptions, the fact remains that entrepreneurs engage in an objectively risky activity—new venture creation with a significant possibility of failure and the potential loss of one’s investment of time, energy, resources, and possibly reputation. Perhaps “fearless”—a word used in T research—may be better a better descriptor than “risk-taker” for entrepreneurs.  

Common Ground between T and E 

While the precise terminology used by E researchers sometimes differs from that employed by T researchers there is a high degree of correspondence between characteristics and traits associated with high T individuals and those associated with entrepreneurs. As illustrated by the following list: 

The correspondence between T behaviors and E behaviors while substantial is not exact or complete. Differences are to be expected since the two research traditions have never been integrated. However, some of the differences may not be as significant as they first seem. For example, self-centered may appear to be different from internal locus of control. But in the testosterone literature self-centered means self-assured and is linked with the ability to control (or dominate) social situations—a concept not so far removed from internal locus of control. 

CONCEPTUAL MODEL & HYPOTHESES 

The basic conceptual model is illustrated in Figure 1. This model proposes that T level influences actions primarily by affecting cognitive processes, or to use the terminology of evolutionary psychologists, psychological mechanisms (Cosmides et al., 1997). These psychological mechanisms affect an individual’s decisions and actions. For theoretical reasons and consistent with prior empirical research, this model asserts that T level positively affects psychological mechanisms; specifically those related to risk tolerance. And these psychological mechanisms affect the likelihood of decisions and actions resulting in a significant entrepreneurial experience. 

In this way the model links the biological (T level), the psychological (risk taking) and the behavioral (significant involvement in a new venture start-up). For the sake of completeness the model also allows for T Level to have a direct effect upon the likelihood of an individual having an entrepreneurial experience, not mediated by a psychological mechanism. However, there is no theory to suggest such an unmediated, direct effect for T. To be parsimonious this model does not specify psychological traits (like innovativeness) that could affect entrepreneurial experience but have no known link to T. 

Consistent with the causal model depicted in Figure 1, and after taking into account appropriate controls it is hypothesized that: 

H1: T level is positively associated with entrepreneurial behavior. 

H2: T level is positively associated with risk taking. 

H3: Risk taking is positively associated with the likelihood of an entrepreneurial experience. 

H4: T level is positively associated with the likelihood of an entrepreneurial experience (after taking into account other effects: H2 and H3). 

Measures and Methods 

Because basal T levels vary during the day and seasonally, and can be affected by exogenous events it is important to collect T samples under controlled conditions. The desired control over collection procedures was most easily achieved with a student population. Accordingly participants in this study were all full-time MBA students at a major North American business school.  

The MBA class was comprised of four sections of approximately 70 students each (both male and female). Timetables were arranged so that data collection took place in two parallel sessions, in two consecutive class sessions during the same day to capture all four sections in a short time frame. Consistent with university research policies students were free to opt out of any or all parts of the study, and to ensure confidentiality student identities were not recorded. Numbers were assigned to all volunteers and these were used to link the data elements. Three data elements were collected from study participants: (1) entrepreneurial background and personal and demographic data, (2) Jackson Personality Inventory scales, and (3) two saliva samples to be assayed for T. 

All students were invited to participate in this study but only male student data was used. The number of female participants was small; 21 volunteers out of 67 female MBA students; 4 self-identified as having a prior entrepreneurial experience. (Subjects taking oral contraceptives were asked to exclude themselves from the study.) There was insufficient data on the female population to do statistical tests. Basal testosterone levels may affect males and females differently so there are issues with pooling male and female data (Bateup, Booth, Shirtcliff, & Granger, 2002). The female data, including saliva samples, were retained for future study. 

Of the population of 205 male students, 166 chose to fully participate in the study (81%). Of these 41 identified themselves as having been involved in a new venture start-up, prior to their MBA studies. Using a convergent sorting process the researchers (professors in strategy and entrepreneurship) assessed the reported new venture involvement of the self-identified entrepreneurs. This check on self-identification was blind, done prior to the determination of T levels. A total of 33 subjects were retained in the entrepreneurship category. The eight students eliminated did not have significant full-time involvement in the new venture; often they were part-time employees, passive investors, or board members. (Subjects who had self-identified themselves as entrepreneurs, but were disqualified after review by the researchers, were not included in the pool of non-entrepreneurial subjects.) Those retained had been the lead in a new venture, including direct personal investment and hands-on management of the new venture. This categorization serves as the dependent variable for our analysis. Fulltime involvement in the creation of a significant new venture is the behavior of interest. We are not predicting a relationship between T and venture success and accordingly, studied business launches rather than outcomes. 

Of the 33 entrepreneurs identified complete and reliable data was available for 29. A pair-matched list of 29 non-entrepreneurs was extracted from the remaining male participants. The pairing was based on the time period during which the saliva was collected, and then age, ethnicity, and undergraduate degree. Time period was selected as the first matching criterion because T levels changes during the day, declining significantly from early to late morning (Nieschlag, 1974). Morning was the only time at which data collection was possible for our study. The first and second data collection sessions were separated by a 50 minute interval. The average T level was 12.5% lower in the later period. Ethnicity was also included as a matching criterion, and examination of the data indicated modest differences among three ethnic categories. (Ethnicity was self-reported in response to the question: Which best describes your ethnic background: African, Asian, Caucasian, Latino/Hispanic, Multi-ethnic; Native American, Other?) Pairs were also matched on age because of the inverse relationship between age and testosterone levels (Lamberts, van den Beld, & van der Lely, 1997). Education, specifically the level and nature of prior schooling, was selected to control for opportunity exposure. As such, engineers were matched with engineers, business majors with business majors, etc. 

To expand the sample size for this study another 53 male subjects, in addition to the identified entrepreneurs and pair matches, were randomly selected from the participant pool for inclusion in the samples to be assayed. This number was determined by the assaying procedures. The laboratory performed testosterone assays in fixed batch sizes based on “kits” of the reagent chemicals. Our final sample of 33 entrepreneurs, 29 matched pairings, and 53 others totaled to 115 subjects, each of whom provided 2 saliva samples which exhausted the maximum available test kit capacity of 230 samples. (One subject, an entrepreneur, was subsequently eliminated from the dataset because he was taking prescription medication that could affect testosterone level. Consequently the final sample was 114.) 

Reported T-levels are the average values of the two samples collected from each participant in picograms of testosterone per milliliter (pg/ml) of saliva. Data means, standard deviations, and inter-item correlation coefficients are presented in Table 1. 

ANALYSIS AND RESULTS 

The initial step in our analysis compared mean scores between the entrepreneurs and non-entrepreneurs in our sample: for the entire sample, and for matched pairs. Multivariate logistic regression analysis was also conducted. 

Mean Difference Analysis 

T-test results, for the full data set and for the initial matched-pair subset are presented in Table 2. These results were consistent with the expectation that entrepreneurs have higher testosterone levels than non-entrepreneurs, within both the full sample and the matched-pair sub-sample. There was also a significant difference in the expected direction for the risk tolerance scale. 

Multivariate Analysis 

We hypothesized that risk tolerance mediateS between testosterone and the propensity to engage in entrepreneurship behavior. This model can be operationalized as a series of relationships. T is a function of subject age and data collection time; control variables in this study (see Equation 1 below). The residual of this relationship can then be used as a predictor of risk tolerance as measured by the JPI, which in turn can be used to estimate the likelihood of prior entrepreneurship (Equations 3, 4 and 5). 

Testosterone (T) =         [1] 

Risk Taking (RT) =                 [2] 

Entrepreneurship (E) =                 [3] 

Entrepreneurship (E) =                 [4] 

Entrepreneurship (E) =             [5] 

This series of equations was estimated using either OLS or logistic regression. Results are presented in Table 3. The column headers indicate the dependent variable under study and the corresponding equation. 

The first column in Table 3 estimates Equation 1 and provides confirmation that the control variables: subject age and the time period when the saliva was collected are both significant influences on T-level. Testosterone levels decline with age and during the day. The second column, Equation 2, indicates that the residual value of T, after removing the age and time-of-day effects, is significantly associated with risk taking. Risk tolerance significantly predicts entrepreneurial behaviour as indicated by the logistic regression of Column 3; as does T-residual in Column 4. Finally, all variables are included in the last column of Table 3 and the model still shows positive and significant results for risk taking and T-residual jointly. 

Taken together, the results from the regression models in Table 3 are summarized graphically in Figure 2. The analysis supports a partially mediated relationship between T and new venture creation with risk tolerance in the mediating role. 

DISCUSSION 

The primary hypothesis of this research that individuals with higher salivary testosterone levels are more likely to behave entrepreneurially, finds general and robust support (Hypothesis 1). T is positively related to E. Also as hypothesized (H2 and H3) there is a positive path relationship between T level and risk taking, and risk taking and the likelihood of an entrepreneurial experience. 

The significance levels for T-related findings of .05 or better are acceptable given the relatively small sample size: 29 entrepreneurs and 81 non-entrepreneurs. With this sample size this level of significance suggests T has a moderate sized and meaningful effect upon E. 

Limitations and Extensions 

There are several possible limitations to the findings from this research. First, in the model causation goes from T to E. But in this study T levels were measured after the entrepreneurial episode, not before. It is conceivable that having an entrepreneurial experience increases T. While possible such reverse causation is unlikely. T levels are affected by exogenous events (Mazur et al., 1998b), but such effects dissipate within a matter of hours, or days at the most. An individual’s basal T level is relatively constant; or more accurately declines at a slow predictable rate after late adolescence, barring any major changes in lifestyle or health. Therefore, if measured earlier but after adolescence the same population of subjects would have had higher T levels. But there is no reason to suspect that any individuals’ relative position within the same population would change significantly. In any event, the sequence of causation question could be addressed with a longitudinal study; by measuring T levels at an early point in the subjects’ work lives, perhaps as they graduate from university, and observing subsequent entrepreneurial behavior. 

This study was done with male MBA students and is subject to the usual caveats about generalizing to the population of practicing entrepreneurs. However, only those subjects with actual new venture start-up experience were designated as entrepreneurs. Therefore these results should generalize to entrepreneurs, at least to that subset of entrepreneurs that return to higher education after their entrepreneurial episode. There is no reason to suspect the T – E relationship would be different for this subpopulation. However, this possibility could be addressed by studying the T level of active entrepreneurs and comparing them to similar non-entrepreneurs. While such a study is feasible, collecting comparable saliva samples under controlled conditions would be challenging. 

For reasons already explained only males were included in the current study. Males and females do have biological differences. Whether these differences affect business behaviors is a sensitive question with wide ranging implications (Foss, 1998). Some prior research has found that T often has a similar (but not always identical) effect in female population as it does in a population of males; even though the basal levels are much lower (Harris et al., 1996; Dabbs, Alford and Fielden, 1998; Bateup et al., 2002). We suspect the same may be true for entrepreneurial behaviors but additional research is required to explore the T – E relationships within female populations. 

This study did not explore T’s relationship to entrepreneurial success. Such a study would be extremely interesting and could be done, but would require a much larger sample size and more resources to execute. We suspect, as found in animal studies (Dufty, 1989), the relationship would be inverted U-shaped. As indicated by our study, individuals with low T levels are less likely to exhibit entrepreneurial behavior. And those that do attempt new venture start-ups are likely to be less persistent. At the other end of the spectrum, extremely high T individuals may take unreasonable risks, persist with lost causes and be egocentric control freaks dominating their employees (Kets de Vries, 1985). This type of individual may initiate a new venture but it is unlikely the venture would grow and prosper under their leadership. 

This study is a promising exploratory step towards linking a heritable biological trait with a specific and interesting business behavior. Until recently testosterone (and other endocrines) could only be measured with blood samples making this type of research difficult and costly. With the development of reliable techniques for salivary assays this research can be more easily and widely done. Such research will lead to improved understanding of how biological differences affect business behavior. 

Implications and Conclusion 

For scholars interested in management and business-related behavior this type of research is largely unexplored territory. T research may help to explain much more about entrepreneurs than just the likelihood that they will be involved in new venture start-up. T may assist in explaining why many entrepreneurs have difficulty fitting into structured hierarchies—they are not comfortable in a subordinate position. Research of this type can also go beyond entrepreneurial behaviors. Biology may influence cognitive preferences. For example, T and other endocrines may help to explain aspects of cognition. The research possibilities are numerous. 

The implications for practice raise interesting questions and possible dilemmas. First it needs to be stated that this study was exploratory, to our knowledge the first of its kind in the organizational sciences. This research has identified a specific measurable hormonal difference amongst individuals and related that difference to an observable business behavior. At this early stage it would be premature to make any prescriptions for managerial practice. However, what if future research verifies and extends the general findings of this research, that individual biological differences influence business behaviors? What could practitioners do with this knowledge? More significantly, what should practitioners do with this knowledge? 

Suppose future research demonstrates a relationship between T and new venture success. Should venture capitalists be allowed to test the T levels of would-be entrepreneurs requesting new venture funding? And, then use that information as part of their decision to fund (or not fund) the entrepreneur’s new venture proposal? Because individuals have no (natural) way to control their hormonal levels many reasonable people would object to this type of testing. Is it socially acceptable to deny someone access to resources based upon a biological factor they cannot control? And if we accept that such testing should not be allowed does that mean the basic research to prove (or disprove) the relationship between a biological difference, like T level and a business behavior, like venture success should not be done? We are enthused by the prospects of further basic research of this type and what might be found. But we recognize the broader implications of this stream of research. 

ACKNOWLEDGMENTS 

We would like to express our appreciation to the SSHRC for providing financial support (MCRI grant # 412980025); Professor James Dabbs for motivating and encouraging this research, Deborah Chiodo and Bavani Rajakumar for their research assistance, and the MBA students who participated in this study. 

CONTACT: Roderick E. White, University of Western Ontario, 1151 Richmond Street, London, N6A 3K7, Ontario, Canada; (T) 519-661-3252; (F): 519-661-3485; rewhite@ivey.uwo.ca 

REFERENCES 

Baron, R. A. (2002) “OB and Entrepreneurship: The Reciprocal Benefits of Closer Conceptual Links.” In Research in Organizational Behavior, eds. B.M. Staw & R.M. Kramer, 24: 225–269. New York: JAI. 

Bateman, T.S. & J.M. Crant. (1993) “The Proactive Component of Organizational Behavior: A Measure and Correlates.” Journal of Organizational Behavior, 14: 103–118. 

Bateup, H.S., A. Booth, E.A. Shirtcliff, & D.A. Granger. (2002) “Testosterone, Cortisol, and Women’s Competition.” Evolution and Human Behavior, 23: 181–192. 

Begley, T. M. & D.P. Boyd. (1986) “Psychological Characteristics Associated with Entrepreneurial Performance.” In Frontiers of Entrepreneurship Research, eds. Robert Ronstadt, John A. Hornaday, Rein Peterson, & Karl Vesper, pp. 146–165. Wellesley, MA: Babson College. 

Bercherer, R.C. & J.G. Maurer. (1999) “The Proactive Personality Disposition and Entrepreneurial Behavior among Small Company Presidents.” Journal of Small Business Management, 37: 28–36. 

Boehm, C. (2000a) “Group Selection in the Upper Paleolithic.” Journal of Consciousness Studies, 7: 211–215. 

Boehm, C. (2000b) “Interactions of Culture and Natural Selection in the Upper Paleolithic.” Unpublished working paper. 

Booth, A., D.R. Johnson, D.A. Granger, A.C. Crouter & S. McHale. (2003) “Testosterone and Child and Adolescent Adjustment: The Moderating Role of Parent-child Relationships.” Developmental Psychology, January. 

Brockhaus, R.H. (1980) “Risk Taking Propensity of Entrepreneurs.” Academy of Management Journal, 23: 509–520. 

Busenitz, L.W. (1999) “Entrepreneurial Risk and Strategic Decision Making: Its a Matter of Perspective.” The Journal of Applied Behaviorlal Science, 35: 325–340. 

Buss, D. M. (1997) “The Emergence of Evolutionary Social Psychology.” In Evolutionary Social Psychology, eds. J.A. Simpson & D.T. Kenrick, pp. 387–400. Mahwah, NJ: Lawrence Erlbaum Associates. 

Buss, D.M. (1999) Evolutionary Psychology:The New Science of the Mind. Boston, MA: Allyn and Bacon. 

Cashdan, E.A. (1995) “Hormones, Sex, and Status in Women.” Hormones and Behavior, pp. 354–366. 

Cosmides, L. & J. Tooby. (1997) Evolutionary Psychology: A Primer. http://www.psych.ucsb.edu/research/cep/ . 

Cosmides, L. & J. Tooby. (1992) “Cognitive Adaptations for Social Exchange.” In The Adapted Mind: Evolutionary Psychology and the Generation of Culture, eds. J.H. Barkow, L. Cosmides, & J. Tooby, pp. 163–228. New York: Oxford University Press. 

Crant, J.M. (1995) “The Proactive Personality Scale and Objective Job Performance among Real Estate Agents.” Journal of Applied Psychology, 80: 532–537. 

Dabbs, J.M.Jr. (1992) “Testosterone and Occupational Achievement.” Social Forces, 70: 813–824. 

Dabbs, J.M.Jr. (1997) “Testosterone, Smiling and Facial Appearance.” Journal of Nonverbal Communications, 21: 45–55. 

Dabbs, J.M.Jr. (2000) Heroes, Rogues, and Lovers: Testosterone and Behavior. New York: McGraw-Hill. 

Dabbs, J.M.Jr., E.C. Alford & J.A. Fielden. (1998) “Trial Lawyers and Testosterone: Blue-Collar Talent in a White-Collar World.” Journal of Applied Social Psychology, 28: 84–94. 

Dabbs, J.M.Jr., F.J. Bernieri, R.K. Strong, R. Campo & R. Milun. (2001) “Going on Stage: Testosterone in Greetings and Meetings.” Journal of Research in Personality, 35: 27–40. 

Dabbs, J.M.Jr., C.H. Hopper & G.J. Jurkovic. (1990) “Testosterone and Personality among College Students and Military Veterans.” Personality and Individual Differences, 11: 1263–1269. 

Dabbs, J.M.Jr., R.K. Strong, & R. Milun. (1997) “Exploring the Mind of Testosterone: A Beeper Study.” Journal of Research in Personality, 31: 557–587. 

Dufty, A.M. (1989) “Testosterone and Survival: A Cost of Aggressiveness?” Hormones and Behavior, 23: 185–193. 

Ellis, L. (1993) Conceptually Defining Social Stratification in Human and Nonhuman Animals. Westport, CT: Praeger Publishers. 

Fiske, A.P. (1991) Structures of Social Life: The Four Elementary Forms of Human Relations: Communal Sharing, Authority Ranking, Equality Matching, Market Pricing. New York: Free Press. 

Foss, J. (1998) “Testosterone and the Second Sex.” Behavioral and Brain Sciences, 21: 374–375. 

Frank, R.H. (1999) Luxury Fever: Why Money Fails to Satisfy in an Era of Excess. New York: Free Press. 

Gartner, W.B. (1994) “Where’s Entrepreneurship: Finding the Definitive Definition.” In Marketing and Entrepreneurship, ed. G.E. Hills, pp. 25–33. Westport, CN: Quorum Books. 

Harris, J.A., J.P. Rushton, E. Hampson & D.N. Jackson. (1996) “Salivary Testosterone and Self-Report Aggressive and Pro-Social Personality Characteristics in Men and Women.” Aggressive Behavior, 22: 321–331. 

Hatch, J.E. & J. Zweig. (2000) “What is the Stuff of an Entrepreneur.” Ivey Business Journal, 65: 68–72. 

Hornaday, J.A. & J. Aboud. (1971) “Characteristics of Successful Entrepreneurs.” Personnel Psychology, 24 

Hull, D.L., J.J. Bosley & G.G. Udell. (1980) “Renewing the Hunt for the Heffalump: Identifying Potential Entrepreneurs by Personality Characteristics.” Journal of Small Business Management, 18: 11–18. 

Johnson, B.R. (1990) “Toward a Multidimensional Model of Entrepreneurship: The Case of Achievement Motivation and the Entrepreneur.” Entrepreneurship: Theory and Practice, 14: 39–54. 

Kets de Vries, M.F.R. (1985) “The Dark Side of Entrepreneurship.” Harvard Business Review, Nov–Dec: 160–166. 

Lamberts, S.W., A.W. van den Beld & A.J. van der Lely. (1997) “The Endocrinology of Aging.” Science, 278: 419–424. 

Low, M. B. & I.C. MacMillan. (1988) “Entrepreneurship: Past, Present and Future Challenges.” Journal of Management 14: 139–161. 

Markoczy, L. & J. Goldberg. (1998) “Management Organization and Human Nature: An Introduction.” Managerial and Decision Economics, 19: 387–409. 

Mazur, A. (1985) “A Biosocial Model of Status in Face-to-Face Primate Groups.” Social Forces, 64: 377–402. 

Mazur, A. & A. Booth. (1998a) “Old Issues and New Perspectives on Testosterone Research.” Behavioral and Brain Sciences, 21: 386–390. 

Mazur, A. & A Booth. (1998b) “Testosterone and Dominance in Men.” Behavioral and Brain Sciences, 21: 353–363. 

McClelland, D.C. (1961) The Achieving Society. New York: Free Press. 

McClelland, D.C. (1965) “Achievement Motivation can be Developed.” Harvard Business Review, 43: 6–24. 

Meikle, A.W., J.D. Stringham, D.T. Bishop & D.W. West. (1988) “Quantitating Genetic and Nongenetic Factors Influencing Androgen Production and Clearance Rates in Men.” Journal of Clinical Endocrinology and Metabolism, 67: 104–109. 

Miner, J.B. (2000) “Testing a Psychological Typology of Entrepreneurship using Business Founders.” Journal of Applied Behavioral Science, 36: 43–69. 

Nieschlag, E. (1974) “Circadian Rhythm of Plasma Testosterone.” In Chronobiologial Aspects of Endocrinology, eds. J. Aschoff, F. Ceresa, & F. Halberg, pp. 117–128. Stuttgart: Schattaquer Verlag. 

Pierce, B.D. & R.E. White. (1999) “The Evolution of Social Structure: Why Biology Matters.” Academy of Management Review, 24: 843–853. 

Richerson, P. J. & R. Boyd. (1998) “The Evolution of Human Ultra-Sociality.” In Indoctrinability, Iideology, and Warfare, eds. I. Eibl-Eibesfeldt & F.K. Salter, pp. 238–262. New York: Berghahn. 

Richerson, P.J. & R. Boyd. (1999) “Complex Societies: The Evolutionary Origins of a Crude Superorganism.” Human Nature, 10: 253–289. 

Robinson, P.B., D.V. Stimpson, J.C. Huefner & H.K. Hunt. (1991) “An Attitude Approach to the Prediction of Entrepreneurship.” Entrepreneurship: Theory and Practice, 14: 7–26. 

Shane, S. & S. Venkatraman. (2000) “The Promise of Entrepreneurship as a Field of Research.” Academy of Management Review, 25: 217–226. 

Sober, E. & D.S. Wilson. (1998) Unto Others: The Evolution and Psychology of Unselfish Behavior. Cambridge, MA: Harvard University Press. 

Stewart, W.H., J.C. Carland & J.W. Carland. (1996) “Empirically Defining the Entrepreneur.” Journal of Business and Entrepreneurship, 8: 1–18. 

Strong, R.K. & J.M.Jr. Dabbs. (2000) “Testosterone and Behavior in Normal Young Children.” Personality and Individual Differences, 28: 909–915. 

Thornhill, N.W., J. Tooby & L. Cosmides. (1997) “Introduction to Evolutionary Psychology.” In Human by Nature, eds. P. Weingart, S.D. Mitchell, P.J. Richerson, & S. Maasen, pp. 212–238. Mahwah, NJ: Lawrence Erlbaum. 

Tooby, J. & L. Cosmides. (1992) “The Psychological Foundations of Culture.” In The Adapted Mind, eds. J.H. Barkow, L. Cosmides, & J. Tooby, pp. 19–136. Oxford: Oxford University Press. 

Udry, J.R. (2000) “Biological Limits of Gender Construction.” American Sociological Review, 65: 443–457. 

Wooten, K.C., T.A. Timmerman & R. Folger. (1999) “The Use of the Personality and the Five Factor Model to Predict New Business Ventures: From Outplacement to Start-up.” Journal of Vocational Behavior, 54: 82–101. 

Wrangham, R.W. & D. Peterson. (1996) Demonic Males. Boston, MA: Houghton-Mifflin.  

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