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Even in relatively simple organisms, learning sets off a continual process of escalating threats and adaptive defenses.

Birds learn that certain color patterns in spiders indicate the presence of poison and they avoid those patterns. Through time, other non-poisonous spiders develop the color patterns of the poisonous types and thus avoid being eaten themselves; a selectively induced learning passed down through generations. Even the process of how animals learn is not immutable. That is, animals have some basic capacity for learning, but they can learn in accelerated ways depending on the environment they are put in.

Monkeys, which are generally considered to have the learning capacity of a human 2 years old, can be trained in experimental settings to learn like a 9 year old, including understanding a sense of their own self as a unique entity interacting with and affecting the world around them. The capacity for learning reminds us that no security adaptation should be assumed to be a safe and everlasting solution, because there is always the potential for an adaptable enemy to learn how to overcome it.


A main reason that security walls and contraband screening don’t work against attackers is that they quickly learn what the barrier is, and how to get around it.

When increased body screening of airline passengers was implemented after 9/11, Richard Reid attempted to destroy an airliner with a bomb in his shoe, and when shoes began to be screened in response to Reid’s attack, Al Qaeda plotted to use a liquid explosive attack, and when liquids were banned, Umar Abdulmutallab used a powdered incendiary hidden in his underwear in an attempted attack.

A wall constructed between parts of the U.S. and Mexico border at a cost of between $1 million and $10 million per mile, slows down illegal immigrants by an estimated 20 minutes, even in its most fortified areas. And on a tiny island in the tiny town of Beaufort, North Carolina there is a tiny outpost of the National Ocean and Atmospheric Administration (NOAA) that studies fish populations and coastal ecology. There is little reason to suspect this outpost is on any terrorist’s list of desirable targets. Yet when the NOAA coastal scientists wanted to renovate and add some space a few years back, they were forced by the Department of Homeland Security to install enormous Wal-Mart style parking lot lights on their facility as a required security measure. This was ironic, since the scientists working at the lab know full well that night time light pollution is a major threat to the ecology of the same coastal marine environments that they are paid by taxpayers to study.


Humans’ability to learn is advanced relative to most other species and accelerated through a high degree of parental care, symbolic language, and communication networks that allow us to learn from environmental threats without actually experiencing them.

In addition to creating a more threatening environment, learning can also greatly aid our security. For example, until 9/11, the normal response to a plane hijacking was to put up no resistance as hijackers made demands that were eventually negotiable and lethal threats were unlikely to be carried out. But on the same day that terrorists began using passenger planes as weapons of mass destruction, humans used networked technology to share information about the change in hijackers’ tactics and passengers on one hijacked plane immediately adapted a more active defense, risking their own security to protect a larger (and largely unrelated) group of humans. Subsequent airborne attack attempts by Reid and Abdulmutallab were similarly stopped by passengers.

Natural security systems acknowledge the capacity for learning and unleash it by giving more power to citizens, rather than small groups of experts, to take part in the security process. In this regard, the TSA’s newly launched “Evolution of Security” program which encourages much greater interaction between travelers and the TSA under the slogan, “Terrorists Evolve. Threats Evolve. Security Must Stay Ahead. You Play a Part” appears to be a step in the right direction. What remains to be seen is whether TSA and other security agencies will move beyond simple analogies and learn the substantive lessons of evolution to select for and nurture more adaptive “natural” security systems.