Random unidirectional change in allele frequencies that occurs by chance in all populations and especially in small populations is known as

Natural selection in which more individuals acquire peripheral character value at both the ends of the distribution curve is

Definitions / Explanation : Genetic drift & Gene migration (gene flow)

 

Evolution that shift the allele frequency in a study consistent direction is called?

In a species, the weight of newborn ranges from $2$ to $5\; \mathrm{kg} .97 \%$ of the newbom with an average weight between $3$ to $3.3\; \mathrm{kg}$ survive whereas $99 \%$ of the infants born with weights from $2$ to $2.5\; \mathrm{kg}$ or $4.5$ to $5 \;kg$ die. Which type of selection process is taking place?

 Definitions / Explanation: Gene Pool