Humans are and always have been a vulnerable species. Compared with other animals, humans are astonishingly vulnerable to their environment. We cannot run very fast, our fingernails are poor substitutes for claws, our skin offers little resistance  to the vicissitudes  of weather, we have no poisonous  fangs. Given this vulnerability, the human species has demonstrated an amazing capacity for survival, even as, long ago, we spread around the globe and into all kinds of climates, always along the way having to find increasingly high energy food to feed our growing brains. We were prey long before we became the most successful predator on the planet. We are therefore  "set" internally to respond to situations of danger more readily than situations that evoke feelings of contentment, satisfaction, or joy. Like other animals, we are biologically equipped to protect ourselves from harm as best we can.

Our basic survival responses are still with us. The most fundamental problem facing humanity may be that  we no longer live in the environments for which those predatory instincts evolved, and for which we adapted so effectively. Our cultural and technological evolution has occurred much fast than any genetically evolved changes can occur. And so we find ourselves at the brink of a number of potential untenable futures that we have ourselves created. This is what we mean when we describe the “tragic nature of human existence”.

Fortunately, being mammals, we evolved another adaptation that helped us to survive and thrive – human social life which originates with parental care and the mother-infant bond and then becomes the basis for all relational development from birth onward. An early human standing alone against a dangerous foe had very little defense. Our ability to form attachments to each other and form social groups has been our best defense and is what has  guaranteed our survival so far. Attachment to our social group is a deeply ingrained structure that derives from our primate heritage. The behavior between mother  and infant, and later between  father  and  infant,  is the foundation stone  for adult bonding, friendliness, and love, all of which are at the heart of social organization.

Unfortunately, all mammals, including humans, demonstrate ambivalence about other people, despite the vital survival importance of human relationships. There is a social response to danger as well. When danger is signaled, people who are attached to each other feel compelled to draw together. This makes a great deal of sense from an evolutionary perspective because human safety is so dependent on the protection of the group.

This increased attachment behavior in the face of danger or threat and in the service of survival has been noted in all social species. As children, our only safety is to be found in the protection of others and therefore, whenever fear is aroused we seek protection from others, even when we are adults. Under such circumstances we also become more obedient and open to suggestion.

As powerfully wired as we are for social contact, so too are we wired for "xenophobia," the  fear  of strangers. This fear begins during the second half of the first year of life, and although it is modifiable by culture it is never totally absent from human social relationships. This inherent  conflict is probably what propelled our evolution into relatively small social groups; we needed social bonds, and yet we had to minimize our fear-arousing contact with strangers. Thus, the perfect solution is a fixed, relatively small group of familiar people [99]. Modern urban life, of course, poses serious problems in this regard. In situations of danger, our sense of stranger anxiety also increases, and our bonding to an in-group  escalates along with our  perception  of threat from an out-group. When we are frightened we want to be with people we trust, and we want  to touch them as well. Tactile communication  is extremely important among primates and humans and has a calming, positive effect [99]. Coming together as a group in times of danger has many obvious benefits. Defense is easier if we are not alone. We can pool our resources and information and better prepare for the danger. We can read each other's level of emotional expression and gauge our own level of arousal accordingly. We can use others to help us modulate our own level of arousal if it is becoming dangerously high. If we are in an avoidant state that could have destructive consequences, other  people can help us confront  the situation without  being overwhelmed  by it, thus increasing our own level of potential competence.

These  biologically-based behavioral sequences are obvious in any kind of disaster and is probably the reason why in these situations people's "stranger anxiety" is so diminished and why people draw together and are more helpful to each other than under other, more normal circumstances.  It is also part of the reason why secret danger is so damaging. The person who must keep silent about a dangerous situation cannot  utilize these innate human responses to help modulate anxiety and arousal.

Built-in Fears of Change

Animals, babies, and human beings in general have a fear of the unknown. Uncertainty means potential threats to survival are out there. We are a conservative species in that our criteria for movement is based at least as much on staying put – since we are alive “here” wherever here happens to be – as it is on moving on. In other words, “things could always get worse”. The more fear-provoking, life-threatening situations a person has encountered, the more threatening uncertainty is. Some people avoid circumstances that evoke fear while others try to control their sense of fear, but regardless of what defensive strategy we employ, it pretty much comes from the same place – life is scary and fear rules.