What two factors can cause variation within a group of living things?

Answer 1

Two factors that can affect variation are: (1) climate (on the colour of the skin, for example); (2) diet (a deficiency of some mineral can cause poor growth for one who has tallness in their genes)

Answer 2

In genetics, there are two ways to increase variation of genetic materials. The first is an independent assortment of genetic material available in each nucleus, the crossing and combining of generations and random fertilization.

Answer 3

Because (in humans) we have the sperm and the egg- both have half the amount of DNA needed for a full person. Scientifically you would say we have "haploid gametes" (haploid is the half DNA bit and Gametes is a term for the sperm or egg)

And because of "Crossing-Over"- in meiosis, the Chromosomes actually swap around before splitting the cell in half and reproducing, so it is completely random.

Answer 4

Mutations are a source of variation in living things, the three forms being numerical, structural and gene mutations. Another source of variation is through sexual reproduction, where you have crossing over in Prophase I of meiosis, random fertilization of gametes as well as mendelian laws of independent assortment and random segregation. What about natural selection?