A genetically controlled trait that increases an individual's fitness.
Variations of a given gene.
A situation in which it is beneficial for a population to maintain two different alleles creating different phenotypes within the population.
Abbreviation for deoxyribonucleic acid, the genetic material of most organisms.
The probability that an individual will contribute its genes to the next generation
All of the genes of all of the individuals in a population make up a gene pool.
The genetic make-up of an individual. Compare with phenotype.
A situation in which a single disadvantageous allele is not selected out of a population, because, when a person is heterozygous for that allele (the person has one disadvantagoues allele and one normal allele), the person gains some sort of local advantage by having the disadvantageous allele. For example, the allele for sickle-cell anemia offers resistance to malaria. If a person in an area high in malaria is heterozygous for sickle-cell anemia, the resistance they gain to malaria outweighs the disadvantage of having heterozygous sickle-cell anemia. A person with two sickle-cell anemia cells in such a region is will not have a greater advantage, even if they are completely resistant to malaria. What's the use of being resistant to malaria if you're blood can't carry oxygen?
The inheritance of different genes independently of each other.
The theory of evolution stating that species change over time and that this change occurs through use and disuse and the inheritance of acquired traits.
Also called neo-Darwinism and the synthetic theory of evolution, the theory of evolution that combines Darwinism with information gained from modern experimental geneticists, population biologists, mathematicians, and paleontologists.
Random changes in the sequence of the DNA in a gene.
The theory holding that competition exists within species, determining which species live to have offspring and pass their traits on to those offspring.
The traits or characteristics an individual displays. Compare with genotype.
A phenotype that is controlled by more than one gene is said to be polygenic
A group of genetically similar individuals that live in the same area and usually interbreed.
The rearrangement of genes on a chromosome that takes place during sexual reproduction.
The creation of a new species.