Natural selection act directly upon <u>Alleles</u>
Explanation:
Genes, such as that of fur color, have many variants called alleles. Natural selection act on the alleles and chooses the best fit for an environment and eliminates the disadvantageous ones from the population over generations. Mutations are a rare occurrence that increases the number of allelic variants of a genes on which natural selection can act upon.
The correct answer would be D) An observation that has a number associated with it.
So they can say the number quicker.
Answer: Birds pick up oil on their beaks, by rubbing against the uropygial or preen gland near the tail, and then rub it over their feathers. This makes the water unable to break through the oil.
Explanation: Hope this helps have a great day :)
<span>The energy transformation in the sun is primarily the change of nuclear energy to light energy.
More Explainable: </span><span>The sun is said to "burn hydrogen" but what that really means is that near the center of the sun there is enough temperature and pressure to cause the fusion of hydrogen nuclei (protons) into helium nuclei (two protons and two neutrons). The fusion (not fission) reaction energy give off energy in a complex way that includes heat and light. The light works its way out from the center of the sun to the surface and eventually out of the surface into space. That is the sunlight we see as well as some light that is outside our range of vision. The light is electromagnetic energy. </span>