Seville Statement and Aggression

The Seville Statement was created to address aggression and violence.
20 initial authors.
Published in 50 journals and magazines.
Translated into 20 languages.
Endorsed by 75 organizations.
It refuted the idea that war or violent behavior is genetically programmed or caused by a single motivation.

Humans have an inherited tendency towards aggression like our animal ancestors.
Genetic methods allow us to recreate phylogenies and understand our relationship to other primates.
We can estimate when we diverged from earlier primate forms.

100 million years ago: mammals split into marsupials and others.
Modern marsupials exhibit less aggression.
Rodents branched off, displaying less violence towards other rodents than other animals.
Primates separated from tree shrews.
Tree shrews are less homicidal than primates.
Great apes: chimpanzees, orangutans, bonobos, and humans.
Gorillas split off from chimpanzees and humans.
There's an intensification of homicide through mammalian evolution.
Humans are among the more homicidal species, alongside chimpanzees.

Chimpanzees exhibit significant violence.
Research from the 1990s has been refined with more data.
Study of chimpanzee groups (Gombe vs. Ngogo) from 1999-2009.
Boundary patrols: Chimpanzees patrol territories looking for other groups.
Territorial Engulfment: The Ngogo group gradually took over the territory of another group.
Systematic Elimination: Over ten years, the Ngogo group eliminated the other rival group.
High Death Rate: Approximately two chimpanzees killed per year in a group of 40-50.

Analysis of ancestral human skulls from 10,000 to 32,000 years ago.
Evidence of Head Trauma: 26% of skulls showed signs of head trauma.
Causes of Head Trauma: Could be accidents or interpersonal violence.
Forensic Analysis: Modern methods applied to a 30,000-year-old skull.
European Skulls: About 25% showed signs of bashing, spearing, arrowing, or beating.
Consistent Trauma: Trauma was related to violence (spearing, arrowing, beating).
Drowning: Some deaths were due to drowning.
Cultural Group: Victims belonged to the same cultural group.

Genes are recipes for proteins that affect cell operation.
No specific "aggression genes" exist.
Genes contribute to brain systems that manage behavior, including aggression.
Evolution and Selection: Aggressive behavior may have evolved due to its functions.
Aggression can serve adaptive purposes.

Wing Waves: Male song sparrows use wing waves to defend territory.
Aggression Display: Wing waves signal readiness to aggress.
Physical Attacks: Rare but devastating, leading to serious injuries or death.
Conflict Resolution: Signals are used to resolve conflict before violence occurs.

FBI Data: Analysis of homicides in the U.S. over 36 years.
Drug-Related: 5% of homicides linked to narcotic drug laws.
Arguments: 24% of homicides stemmed from arguments.
Honor and Self-Respect: Many homicides result from perceived violations of honor or self-respect.
Revenge: Fundamental desire for revenge when harmed.
Third-Party Aggression: Provoked individuals usually aggress against the provoker, not a third party.

Hobbes believed a Leviathan (strong central power) was needed to prevent humans from tearing each other apart.
State of Nature: Without a state, individuals must defend their interests and are at risk.
Best Defense: A willingness to victimize others to avoid being victimized.
Extortion: A desire to extort a higher valuation from others through damage.
Hamilton-Burr Duel: Example of Hobbesian obsession with defending honor.

Humans have neural systems to regulate aggression.
Sensory Information: Systems take cues from the environment indicating potential harm.
Direct Motor Pathway: Creates innate, reflex-like aggressive responses.
Species-Specific: Responses are specific to humans.
Social Cues: Assessing whether others value you appropriately.
Emotional Responses: Interpreting smiles and other social cues to gauge intentions.