Artificial Selection is a form of selection in which humans actively choose which traits should be passed onto offspring. Humans have used selective breeding long before Darwin's Postulates and the discovery of genetics. Farmers chose cattle with beneficial traits such as larger size or producing more milk, and made them breed; and although they may have known nothing about genes, they knew that the beneficial traits could be heritable. The farmers selected for certain traits in their cattle and probably noticed that the offspring were becoming more and more productive with each generation. Scientists study these traits and spend a lot of time calculating how heritable these traits can be. The more these traits are expressed in the offspring (i.e. size, milk production, etc), the more heritable these traits are said to be. Hunting is also a form of artificial selection, with the genes that humans "want" (i.e. - the biggest buck with the most points, the largest fish, etc.) being removed from the gene pool, allowing the less "wanted" genes to pass on to the next generation by increasing their odds of mating when compared to the hunted specimens.
<span>Why is carbon so abundant in living things when oxygen is the most abundant element on Earth?
</span>a. Carbon atoms can bond with one another to make chains and cyclic structures whereas oxygen atoms cannot form chains or cyclic structures.<span>
Explanation: The aorta is the largest artery in the body. It carries oxygenated blood from the left ventricle of the heart into systemic circulation. The aorta has many subdivisions that branch off into smaller arteries.
