What is fitness in biology?
Q: What is fitness in biology?
A: Fitness in biology is the relative ability of an organism to survive and pass on its genes to the next generation.
Q: Is fitness an important idea in evolutionary theory?
A: Yes, fitness is a central idea in evolutionary theory.
Q: How is fitness usually measured?
A: Fitness is usually equal to the proportion of the individual's genes in all the genes of the next generation.
Q: How does natural selection occur?
A: If differences in individual genotypes affect fitness, then the frequencies of the genotypes will change over generations; the genotypes with higher fitness become more common. This is the process called natural selection.
Q: What determines an individual's fitness?
A: An individual's fitness is caused by its phenotype, and passed on by its genotype.
Q: Are the fitness of different individuals with the same genotype necessarily equal?
A: No, the fitness of different individuals with the same genotype are not necessarily equal. It depends on the environment in which the individuals live, and on accidental events.
Q: What does the fitness of the genotype reflect?
A: Since the fitness of the genotype is an averaged quantity, it reflects the reproductive outcomes of all individuals with that genotype.
