The most likely explanation for the variation is the offspring were produced from different combination of genes. A single pair of gold fish mentioned in the question means a male and a female gold fish. The two of them mated and contributed different genes to the fertilized fish eggs, this results in production of various body shape and colouration which is known as variation.
Answer:
Photosynthesis removes CO2 from the atmosphere and replaces it with oxygen.
Explanation:
Photosynthesis removes CO2 from the atmosphere and replaces it with oxygen. By respiration, O2 is removed from the atmosphere and replaced with CO2. However, these processes are not balanced. Some organic matter is not oxidized. (I'm very sorry if I'm wrong but I believe it's that)
Answer:
A malaria outbreak causing allele frequencies to change is an example of <u><em>natural selection.</em></u>
Explanation:
Natural selection is a type of selection in which those organisms are favoured to live and reproduce which are better adapted to live in an environment. Due to natural selection, the allele frequencies of a population will tend to change with the passage of time.
When the outbreak of malaria occurs, those organisms which do not catch malaria are able to survive and pass on their characteristics to their offsprings. the other organisms die and do not reproduce. This will cause changes in the allele frequencies.
