Some isotopes, however, decay slowly, and several of these are used as geologic clocks. Dating rocks by these radioactive timekeepers is simple in theory, but the laboratory procedures are complex. <span>All methods rely on the fact that certain elements (particularly uranium and potassium) contain a number of different isotopes whose half-life is exactly known and therefore the relative concentrations of these isotopes within a rock or mineral can measure the age.</span>
Answer:
False
Explanation:
Genetic variation is the difference in the sequence of DNA in the individuals of a population and a heterozygote has more genetic variation that homozygote person because heterozygote has two different alleles of a gene while homozygous individual have two same alleles.
Heterozygotes have advantage over homozygotes because it protects the individual from many genetical diseases and increase the genetic variation by increasing the gene pool in the population. So higher fitness results in more genetic variation in the population therefore the statement is false.
Answer:
Answer is A. Vicariance does not require organisms to disperse.
Explanation:
Vicariance occurs when there is a sudden occurrence barrier , such as geographical area barrier that cause the isolation of species of organisms.
Dispersal involves the movement of the organism while vicariance is the change in environment due to sudden occurrence in the area.
In this case, vicariance does not involve movement of organisms while dispersal involves movement of organisms.
