Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
18 Cards in this Set
- Front
- Back
|
Traditional view of human variation
|
focused on attempts to classify humans into races
|
|
|
Current trend in view of human variation
|
focuses on the genetics and adaptive significance of human variation
|
|
|
Historical view: Biological determinism
|
cultural and biological variations are inherited in the same way
|
|
|
Historical view: Eugenics
|
"race improvement" through forced sterilization of members of some groups and encouraged reproduction among others (popular in 1930s and basis of Nazi ideas about race)
|
|
|
Concept of race
|
-Humans are all members of same “polytypic” species
-Homo sapiens |
|
|
Forensic anthropologists concentrate on phenotypic variables to indentify:
|
sex, age, stature, and ancestry
-Can establish broad population affinities with about 80% accuracy |
|
|
Polymorphisms
|
Characteristics with different phenotypic expressions
|
|
|
A genetic trait is polymorphic if:
|
the locus that governs it has two or more alleles.
|
|
|
Geneticists use polymorphisms as a tool to:
|
understand evolutionary processes in modern populations
|
|
|
Human Genome Project given remarkable insight into human variation at DNA level
|
1) verify earlier genetic evidence of recent African origin of modern humans
2) show genetic relationships between populations 3) provide evidence of the role of genetic drift (founder effect) |
|
|
POPULATION GENETICS
|
-Measures and explains evolutionary changes in contemporary populations
-The study of the frequency of alleles, genotypes, and phenotypes in populations from a microevolutionary perspective. |
|
|
Population
|
-A group of interbreeding individuals
-A group where one is most likely to find a mate -Such a population shares a “gene pool” |
|
|
Gene Pool
|
the total complement of genes shared by the reproductive members of a population.
|
|
|
mate choice factors
|
Geographical, ecological , and social
|
|
|
Breeding Isolates
|
populations that are isolated geographically and/or socially from other breeding groups
|
|
|
Determining evolution Using “population genetics” approach
|
• 1) First specific human populations are identified
• 2) Next measure allele frequency for specific traits • 3) Compare frequencies with set predicted by mathematical model – the “Hardy-Weinberg equilibrium” equation |
|
|
Hardy-Weinberg “Equilibrium”
|
-The central theorem of population genetics.
|
|
|
Factors that Act to Change Allele Frequencies
|
-New variation (i.e., mutation)
-Redistributed variation (i.e., gene flow or genetic drift) -Selection of “advantageous” allele combinations that promote reproductive success (i.e., natural selection). |
