In the last article we looked at natural selection, a process which leads to evolution. We saw that if an organism has advantageous alleles, it is better adapted to its environment and is more likely to survive and reproduce. In today's article we will look at the different types of adaptions that organisms can have... Continue Reading →
Natural selection is one way that evolution occurs. Evolution is the change in allele frequency over time. In this article we will look at the process of natural selection, and a few different types of selection. Note that there can be other mechanisms behind evolution as well, such as the genetic bottleneck effect described here.... Continue Reading →
Genetic diversity is defined as the number of different alleles of genes in a population. Last week we looked at one method of introducing new alleles into a population - by genetic mutation. Today we will look at other ways that genetic diversity can be increased or decreased, and how it can be measured. Increasing... Continue Reading →
There is a huge variety of life on this planet. In this series we will look at how all that variation exists, from the DNA level to the population level. Today we are starting off with a source of variation at the DNA level. What are mutations? A genetic mutation occurs when the DNA base... Continue Reading →
In the last article we looked at meiosis - the type of cell division that produces haploid gametes in the reproductive organs. Today we're going to look at how meiosis can produce genetic variation in the gametes, and therefore genetic variation in offspring after the gametes fuse at fertilisation. We will also finish off by... Continue Reading →
Meiosis is a little more complicated than mitosis, and has a different outcome. Meiosis is a method of cell division which only happens in the reproductive organs of organisms which reproduce by sexual reproduction. It produces genetically different gametes with half the number of chromosomes as the parent cell. These gametes (the egg cells and... Continue Reading →
