Answer:
Natural selection can be described as a phenomenon in which individuals of a population which are better adapted to survive in an environment are favored by nature as compared to the individuals of the population which lack better characteristics to survive in the environment.
Through natural selection, evolution occurs and the allelic frequency changes over a period of time. The process of evolution as well as change in the allelic frequencies does not occur just by a single individual, rather it is a collective effort which takes a lot of time. Hence, we say that natural selection changes the population and not a single individual.
If want a direct answer it would be the decrease in mice, but if you want to get technical the decrease in grain spills caused mice to leave so that would be the indirect cause
Human migration is the movement over long distances, movement from one country/region to another ) by people . Humans moved because of the c<span>hanging climate and landscape and inadequate food supply. </span>The first human movement was t<span>he movement of </span>Homo erectus<span> out of Africa across </span>Eurasia<span> about 1.75 million years ago. </span>
Than industrialization<span> encouraged migration wherever it appeared.
Wars also created migration. (</span><span>The First and Second World Wars, and wars, genocides, and crises sparked by them, lead to migrations).</span>
Like DNA, RNA polymers are make up of chains of nucleotides. The sugars they are made up of; a five carbon ribose sugar.
Or Pentose Sugar.
