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History of Behavior Genetics
When understanding what is behavior genetics, it's important to understand its history. The concept of behavior genetics began with the studies of hereditary and human activity conducted by Sir Francis Galton in the late 1800s. While his research did not use the term “genetics," much of what his work revealed pointed to early evidence to support the overall influence of genes in how humans react to certain situations. In its most basic sense, Galton's study of hereditary factors in individuals, particularly royalty and upper-class English aristocracy, identified the prevalence of biological variation within the human genome.
Above right: Sir Francis Galton in the 1850s. (Supplied by Fastfission at Wikimedia Commons; Public Domain; http://upload.wikimedia.org/wikipedia/commons/e/ec/Francis_Galton_1850s.jpg)
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How Behavior Genetics is Studied
The first step in establishing a legitimate study of behavior genetics is to find an intelligent way to isolate a specific problem. Certain behaviors are hard to classify in any field, within genetics it can be even more challenging. To accomplish a definite research project, one must analyze the behavior to a full degree. The next step is to isolate the genes responsible for the traits. Like many physical features of plants and animals, behavior is very complex and results from multiple genes in the DNA structure.
One of the best ways to conduct research into the genetics of behavior is to study many generations of humans or animals, specifically families. Often, the same behavior is identifiable in the entire population of a certain set of subjects, other times it can only be seen in individual specimens. By identifying genetic variances in the families or subject groups and comparing the results to the behaviors analyzed, researchers can determine which genes are responsible for which behavior.
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Problems with the Genetics of Behavior
The most challenging aspect of this subsection of genetic study is the fact that the “nature versus nurture" factor plays an important role. How much of what a person or animal does is hereditary and how much is learned? This becomes particularly tricky when dealing with humans who often exhibit similar behaviors as each other, especially when it comes to families.
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How Do We Know Genetics and Behavior are Linked?
What is behavior genetics in reality? Judging from certain behaviors of specific species, we can determine that a certain amount of the activity conducted by subjects is hereditary. For example, certain dogs have a tendency to maintain an instinctive need to retrieve objects even when a subject is removed from other dogs at an early age. The dog can be raised in relative isolation but still exhibits the same skills as a dog that has grown around other subjects.
Additionally, the fact that certain actions of genetically similar animals show that many behaviors are engrained in cross-species genes. This can easily be identified using chimpanzees and humans who share 98 percent of like DNA. Activities such as nurturing young are nearly identical between the two species, meaning there has to be a genetic link in the behavior. Essentially, a shared gene or combination of genes is responsible for this conduct.
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"Behavioral Genetics" Human Genome Project: http://www.ornl.gov/sci/techresources/Human_Genome/elsi/behavior.shtml
Behavior Genetics Association: http://www.bga.org/