Family Law and Evolution, Behavioral Genetics

Research Project

Project/Area Number	18530083
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	New fields of law
Research Institution	Hosei University
Principal Investigator	WADA Mikihiko Hosei University, Faculty of Law, Professor (10261942)
Project Period (FY)	2006 – 2007
Project Status	Completed (Fiscal Year 2007)
Budget Amount *help	¥1,680,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥180,000) Fiscal Year 2007: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000) Fiscal Year 2006: ¥900,000 (Direct Cost: ¥900,000)
Keywords	gender / family law / evolutionary biology / civil code / law of inheritance / evolutionary psychology / ethics / game theory / 遺伝学 / 適応度 / 自然法
Research Abstract	The present research focuses on the question “What is law ? What is the evolutionary foundation of human law ? " using the Japanese family law and law of inheritance as sample material. 1. Chapter 1 “Family Law and Evolutionary Biology" deals with the following: (1) The financial duty of ex-husband to support his ex-wife after divorce was analyzed by using evolutionary biology, focusing on the sex difference, and then was thereby concluded valid. (2) The reason why human males did group hunting during the hunter-gatherer age was not only to acquire affluent and good protein, but also to get all the males of the group out for hunting during the day, so that none of the males would “cheat" and mate with females, which then make the group males confirm the father-child relationship by assuring monogamous sexual relationships. 2.Chapter 2 “Family Law, Law of Ineritance and Evolutionary Psychology" deals with the following: (1) Duty of keeping monogamous sexual relationship amongst married human couples can be explained and justified by “jealousy", which has been the object of recently developed evolutionary psychology. (2) When the person who passed away has no children or parents, his/her only heir is the married parter and “takes it all," based on the Japanese law of inheritance. This can be explained by evolutionary psychology of “commitment for investment on carrying forward the genes of the married partner." (3) What behaviors are desired to be “done in my sight (DIMS) " or “done out of my sight (DOMS), in relation to general (legal) behaviors. 3. Chapter 3 “The Elavators ' Dilemma: How Ethics and Law Evolve" deals with case analyses of people, who have to choose between “normal" elevator button and “for-the-handicapped" elavator button, and essays to explain how ethics and rules, and finally laws evolve.