Text for Sexual Selection: Mind Your Mothers! (revised)

Making order
Cooperation and selfishness have their analogs in physical systems (Brody, in press), analogs sometimes labeled as clocks and clouds (Popper, 1965/1985) or as order and chaos (Kauffman, 1995). In humans, most females are more biased than males towards extended cooperative networks. That is, females develop more anxiety disorders than males (Mash & Dozois, 1996) and are more sensitive to facial and vocal displays and are less physically assertive. Males are more likely to exhibit disruptive behavior disorders (Mash & Dozois, 1996). Females have preferences in the contexts of mating with males and of rearing them. These preferences exert a restraining influence on the conduct of males.
Maternal investment in young rhesus
1. Young male rhesus are reared in matrilineal groups that span several generations.
2. Maternal/aunt/grandmother investment duration is typically 2 years, after which they are evicted into male gangs where 50% die.
3. Matrilineal contact is shortened to 1 year for hyperactive, impulsive males who do not make eye contact, have frequent injuries, and often get into fights with larger rhesus. Eviction at 1 year leads to death (Suomi, 2000).
4. Decreased maternal investment in lab conditions (rearing with peers but without mothers) produces a frightened clinging to peers, clumsy play, higher cortisol reactivity, later explosive aggression, and lower 5 HIAA in CSF (Suomi, 2000). Increased maternal/aunt investment under wild conditions will sometimes move a reactive infant into troop leadership (Suomi, 1997). Smuts (2000) has indicated that similar patterns can be seen in baboons.

Hypotheses
Disclaimer: The following statements will each be characterized by a "norm of reaction" and substantial individual variability. On the average, males are different from females but there is substantial overlap in the traits exhibited by each gender.
Each of these hypotheses relies on and extends current evolutionary, clinical and educational literature, research that is now separated according to discipline.
1. Maternal investment is a significant factor before and after birth especially for males. Given high variability in male fitness, maternal investment (paternal, instructional, pediatric attention, and legal) will concentrate on male social behavior more than on females.
2. Female standards for male children will parallel those shown for choosing and retaining adult male partners: kindness, intelligence, political skill, and physical health will be valued (Buss, 1994); the content of psychological assessments will highlight the absence of these traits.
3. Hyperactivity and impulsiveness in young males will distress adult females more than adult males and mothers more than fathers. Females, more than males, will: avoid impulsive males when teaching them, issue classroom sanctions and eviction, make referrals to supplemental instruction, initiate teacher conferences and teacher-parent conferences, make appointments for medical or psychological help, and spend resources for supplemental learning experiences intended to correct lapses in cooperation, impulse control, and academic prowess.
4. Maternal distress will be greater than paternal distress as reflected in meeting attendance, therapies initiated, and medications used (for mother and for son). Maternal protection will be evidenced by disputes with school staff, protests against diagnostic labels that imply lessened fitness and a reluctance to give helpful medications on weekends. ("He only needs it for school.") Homeopathic remedies will be sought first (Brody, 1997). On the other hand, mothers will more freely give medication for large family gatherings, religious observances, and school where other adult females, especially from her family, will be present.
5. Maternal distress will be greater for mental disabilities than for physical in a technical society, greater for physical than mental in rural and pre industrial societies. Maternal depression will be correlated with the peaks and valleys of her son's academic and sports career. To the extent that family anchors are more consistent through the mother's side, she will be more upset about her son's social lapses when he is with her kin than when he is with his father's kin.
6. Greater maternal investment can be correlated with enhanced social outcomes even for impulsive children. However, impulsiveness in either the mother or in the child (or both!) will erode long term achievement for them with each other or in regard to other people. Impulsiveness in combination with mood disorders in either party will multiply the difficulties associated with impulsiveness.
7. As males mature, ever stricter standards for fitness, political skill, and impulse control will be applied by teachers, peers, likely mates, ministers, and female supervisors.

Selection across developmental stages
The negotiated fetus
More human males are conceived than delivered (1.6-1.2/1 vs. 1.05/1, Spreen et al., 1995) sometimes due to allergic reactions between mother and her son (Spreen et al, 1995) and to conflicts over maternal physical resources (Haig, 1993). Placental and fetal traits are a compromise between imprinted genes donated by the father and the mother. Infants that pass maternal physiological standards are carried to full term and have fewer developmental impairments, less impulsive behavior, and higher IQs (Spreen et al, 1995).
The difficult child
The difficult child (males are routinely show greater incidences at all ages for externalizing disorders, Mash & Dozois, 1996) pushes mother away, does not hug, make eye contact, or smile. These traits are associated with frequent crying and disrupted sleep and eating patterns. The easy child (40% of newborns) eats and sleeps well and socializes by making eye contact, smiling, and hugging (Thomas & Chess, 1977). These behaviors are powerful eliciting and reinforcing stimuli for continued maternal investment. Like Suomi's impulsive rhesus, however, difficult human children often elicit maternal scolding, sleep loss, social withdrawal from the child and from her kin, and grieving.
Evicted from day care
Sapolsky has recently linked hours of day care participation to subsequent aggression. There are similarities to Suomi's observations with rhesus: curtail maternal investment and the child becomes more irritable and possibly more impulsively disruptive. The converse is true. Aggression, hyperactivity, and lack of concentration can lead to seriatum day care expulsions, especially if parental resources are limited and the mother is depressed or inconsistent. Males appear to be of greater risk than females. Early onset is associated with higher familial concordance. Unfortunately, early treatment predicts worse, not better, outcomes.
Grades K - 12
Maternal distress may be influenced by offspring popularity or sports prowess as well as academics. Will these effects be greater for sons than daughters? Is there a content x sex interaction? That is, will mothers tend to worry more about deficits relevant to fitness and resources for sons but about social acceptance and physical attractiveness for daughters?
Impulsive males have difficulty with behavior inhibition, task planning, task completion, and social interactions. Word retrieval is lessened (consistent with prolonged stress and possible hippocampal involvement); I.Q. is often 7-13 points below average. These characteristics are consistent with Attention Deficit Hyperactivity Disorder (ADHD) (A.P.A., 1994; Barkley, 1996, 1997)
ADHD is:
- The 2nd most heritable childhood mental disorder and has a 40% overlap with other physical disorders (e.g. allergies, ear infections, various asymmetries) and heightened emotionality (misdirected and disproportionate anxiety, depression, or anger).
- Associated with a lower I.Q. and disrupted executive functions in regard to time, memory, word retrieval, rule generation, and self regulation in contexts that involve social interaction or delayed reward (Barkley, 1996, 1997).
- Seen internationally, affecting approximately 5% of males, 1% of females. While impulsive traits occur to about the same degree in every culture studied, the compensations for these traits vary substantially. Some cultures are similar to the rhesus, rearing their sons first with females and then graduating them to groups of males.
- Is associated with a lack of bonding with female teachers who may spend 30% less time with a hyperactive male. ("The teacher doesn't like me" appears to be true.) There may be better performance for male teachers.
Hyperactivity is an amplifier: high activity level that is not associated with clumsy errors can be a positive factor in popularity and mate selection and may be a sign of fitness. As with the rhesus, higher activity level makes social errors more obvious and more annoying to peers and adults. Children with attention and memory problems but without high activity level and without lapses in social cooperation often pass unnoticed. ADHD (high activity and social clumsiness) has been the topic of 6000+ studies (as of 1995), more than of any other childhood disorder. Inattention without hyperactivity has received 1/20 the research investigation. A similar disparity occurs with respect to clinic referrals, medication, and educational accommodations.
Conduct problems: Moderation in all things
Some young males are lively and sometimes refuse to cooperate with adult rules but have a slightly higher than average IQ and are socially manipulative, often popular with peers while annoying to adults. This 2nd group should not be considered impulsive (Brody, 2001).
More extreme antisocial behavior (arguing with adults and peers, lying, breaking rules, running away from home, cruelty to animals and to other people, fighting, property destruction, setting fires, and stealing) can be distinct from impulsiveness. Again, activity level amplifies either fitness or clumsiness. Children who are skillful, even if annoying, will achieve leadership roles. However, children who are both active, impulsive, and antisocial are more likely to get adult sanctions and peer rejection and at an earlier age.
A withdrawal of maternal investment in the forms of parental inconsistency and maternal depression are strongly associated with argumentative and antisocial behavior. Parental conflict can increase cortisol levels in children (Flinn, 1999) and may increase hyperactivity and disrupt normal executive functions whether in impulsive or in non impulsive children.
Other life transitions
Marriage and divorce
Impulsive males date and marry later; impulsive females are prone to early pregnancy out of wedlock.
"My God, being married to him is like having a 3rd kid," archetypal annoyed wife. There is evidence to suggest that the same males who were in trouble with their teachers will have difficulty with mate retention. The complaints include: aggression, lack of attention to wife or children, social immaturity and disorganization, reckless driving and spending, frequent job changes, erratic child rearing, and being self centered (interrupting, lack of eye contact, preoccupation with television or sports).
Female bosses of impulsive males
Data are needed to determine if impulsive males are more likely get fired by female supervisors than by males and whether arguing, unreliability, or social clumsiness is the greater factor.
Several studies of normal men have shown them "blind" to photographs of annoyed women (Goos & Silverman, 1999). Similar investigations might be made for normal and impulsive males to see if the same pattern exists equally in both groups of males.
Faith of our mothers
Systematic evolutionary data are not available about religious participation and maternal control of impulsive males. However, females appear more likely to attend religious observances, particularly in faiths that advocate cooperation, kindness, and delayed gratification. (Females appear to select their gods by the same criteria they apply to prospective husbands.) Males often select themselves out of formal religious observances, sending their wife and sons to church, preferring for themselves the more immediate (impulsive?) gratification of staying in bed, reading the paper, or watching sports. Impulsive males, on the other hand, select themselves, through their wives, into church social programs for marital instability, child rearing, blended families, or drug and alcohol abuse. On the other hand, it may be that religions that emphasize immediate gratification, aggression, and risky behaviors tend to have greater male participation and more female exclusion. Cross cultural comparisons should be informative.

Conclusions:
It may be useful to view female social control of young males as an extension of genomic conflicts that begin at conception and have a quality control function in regard to human social interaction, one that reduces variance in male conduct and aligns it with female interests. Further, these social negotiations have similar functional properties to reciprocity mechanisms that are studied in statistical physics (Ball, 1999).
In terms of Suomi's observations:
1. Young male humans are reared in groups of female relatives and their extended phenotypes (teachers, counselors, pediatricians, and psychologists).
2. Maternal/aunt/grandmother/teacher investment lasts 12 years. Commitment will vary in accord with the child's cleverness, reciprocity, social consistency.
3. Investment duration is shorter and more tentative for males who do not make eye contact, are impulsive, and get into frequent fights. Eviction from maternal protection is associated with reduced social and academic achievement . Socialization is handled by special education and alternative schools that remove disruptive males from the mainstream society of their peers. Severe externalizing behaviors (ODD, CD, BPD) are often associated with eviction from the maternal home.
4. Increased maternal/aunt investment will sometimes move a lively and highly determined, but not impulsive, young male into troop leadership (Suomi, 1997). There may be a significant interaction between a preschooler's ability to make eye contact, stick to tasks, and use social skills---albeit for selfish ends---and maternal advocacy. Clinical observation suggests that mothers of oppositional sons (and sometimes daughters) form a micro environment for their offspring, one that starts with the child's extended demands for his mother to sleep with him through the night. As he ages, mother handles the bi-directional conflicts between him and outsiders in school and sometimes in the courts while he acquires the social inhibition and material resources to pursue his self interests without her. The difference between maternal advocacy and withdrawal may lie not with the child's activity level but with his physical health and his ability to cling, make eye contact, and maintain reciprocity with her.
Attention Deficit Hyperactivity Disorder has been portrayed not as a lapse in executive functions but as a former "adaptation" that is "mismatched" to the modern era (Hartmann, 1993/1997; Jensen et al, 1998). ADHD is not an adaptation (Brody, 2001). Normal human executive functions may be the result of recursive genetic activity that created one more layer of cortical development, perhaps the result of a comparatively small mutation in a regulatory gene. If so, then ADHD may reflect the incomplete penetration of that mutation into the larger population.
Mothers, more than fathers, are quarterback, coach, counselor, project manager, and battle field medic for sons for the first several years. This difference between mothers and fathers appears to be an exception to inclusive fitness theory that explains investment in kin as the result of shared genes. Indeed, there is probably no culture where fathers take primary responsibility for infants.
Her investment seems proportional to her reproductive opportunities in comparison with males. Women can reproduce, in theory, every 9-12 months; males, again in theory, every 20 minutes. Her future investment may be proportional to her past investment during pregnancy and early rearing and to her opportunities for resources and protection after her son matures.
Further, there is some basis in evolutionary studies for reciprocity expectations to vary in proportion to past investments (Ridley, 1996). Thus, there is less surprise that mothers, more than fathers, experience anxiety and take corrective measures in regard to her son's present and futures. However, it may also be that paternal and maternal investment take different forms: mothers experience anticipatory anxiety and fathers show retaliatory rage and the fitness costs of their investments might be roughly equal.
A more complex argument but anchored on female reproductive assets, might be developed for females and their relationships with their parents, peers, and instructors. That is, will mothers, on the average, value the same characteristics in their daughters that adult males value in women? Or will daughters have the dual task of competing not only for male preferences but also for standing within male and female social hierarchies? And has this dual task made female minds more complex than male?
Finally, it might be expected that niche benevolence will reduce competitive mating pressures on both males and females and on parental expectations. Both genders might, on average, become more alike. At the same time, variation within each gender should increase as genetic and environmental variance interact and allow individuals to have a better match to their nature.
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Mother environment and active genotype-environment correlation:
"My husband was the youngest child and very emotional so his mother spoiled him terribly. After he finished seminary, he could still get away with anything because he found parishioners that loved him."

References
American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (4th Edition). 1994; Washington, D.C.
Ball, P. (1999) Transitions still to be made. Nature, 402, 73-76.
Barkley, R. (1997) ADHD and the Nature of Self Control. NY: Guilford.
------------- (1996) Attention-deficit/hyperactivity disorder. In Mash, E & Barkley, R, (Eds.) Child Psychopathology, Guilford, NY, pp. 63-112.
Brody, J F. (1997) Bait Poisoning and why kids complain about their medication. Journal of Child and Adolescent Psychopharmacology, 7(1), 71-72.
------------- (In press) From Physics and Evolutionary Neuroscience to Psychotherapy: Phase Transitions and Adaptations, Diagnosis and Treatment. In G. Cory & R. Gardner (Eds.) Frontiers & Convergence: The Evolutionary Neuroscience of Paul MacLean, Praeger-Greenwood, due 2002.
------------- (2001) Evolutionary recasting: ADHD, mania, and their variants. Journal of Affective Disorders, 65(2) 197-215.
Buss, D. (1998) The psychology of human mate selection: Exploring the complexity of the strategic repertoire. In C. Crawford & D. Krebs (Eds.) Handbook of Evolutionary Psychology. Mahwah, NJ: Erlbaum, pp. 405-430.
Flinn, M.V. (1999) Family environment, stress, and health during childhood. In C. Panter-Brick & C. Worthman (Eds.) Hormones, Health, and Behavior. pp. 105-138. Cambridge: Cambridge University press.
Goos, L. & Silverman, I. (1999) Sex related factors in the perception of threatening facial expressions. Presented at Annual Meeting, Human Behavior and Evolution Society, Salt Lake City, Utah.
Haig, D. (1993) Genetic conflicts in human pregnancy. Quarterly Review of Biology. 68, 495-532.
Hartmann, T. (1993) Attention Deficit Disorder: A Different Perception. Underwood, NY.
Jensen, P., Mrazek, D., Knapp, P., Steinberg, L., Pfeffer, C., Schowalter, J., & Shapiro, T. (1997) ADHD as a disorder of adaptation. J. Amer. Acad. Child Adolescent Psychiatry. 36(12), 1672-1679.
Kauffman, S. (1995) At Home in the Universe. NY: Oxford.
Mash, E. & Dozois, D. (1996) Child psychopathology: A developmental-systems perspective. In E. Mash & R. Barkley (Eds.) Child Psychopathology. NY: Guilford.
Popper, K. (1965/1985) Indeterminism and human freedom. In David Miller (Ed.) Popper Selections. Princeton, NJ: Princeton University Press.
Ridley, M (1996) The Origins of Virtue: Human Instincts and the Evolution of Cooperation. NY: Penguin.
Smuts, B. (2000) Personal communication.
Spreen, O., Risser, A., & Edgell, D. (1995) Developmental Neuropsychology. NY: Oxford.
Suomi, S. (2000) How gene-environment interactions shape individual development trajectories in rhesus monkeys. Presentation at "The Relationship System," Georgetown Family Centers, Washington, D.C., April 15-16, 2000.
Suomi, S. (1997) Nonverbal communication in non human primates: Implications for the emergence of culture. In Segerstrale, U. & Molnar, P. (Eds.) Nonverbal Communication: Where Nature Meets Culture. Mahwah, NJ: Erlbaum. pp. 131-150.
Thomas, A. & Chess, S. (1977) Temperament and Development. NY: Brunner/Mazel.

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THANKS FOR HER MATERNAL INVESTMENT:
"Sure thing I can do it." Dori LeCroy. email: DoriLeCroy@aol.com.

MANUSCRIPT AND CONTACT INFORMATION:
James Brody, Ph.D, 1262 West Bridge St., Spring City, PA 19475, USA.
Voice phone: 610-948-5344; email: jbrody@compuserve.com.

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