These fossils are very useful for us because we can use them to date the layers of rock that they are found in. Fossils that can be used in this way are called index fossils, and rock layers with the same index fossils in them can be correlated. Not my answer, link here for full
http://peter-mulroy.squarespace.com/correlating-rock-layers/
T<span>he least likely to be a source of genetic variation among living organisms is D. asexual reproduction. Asexual reproduction is a kind of reproduction that does not include fertilization process of two gametes: female and male but only includes parts of plants or cells. In this case, variation is minimized</span>
Density-dependent regulation can be affected by factors that affect birth and death rates such as competition and predation. Density-independent regulation can be affected by factors that affect birth and death rates such as abiotic factors and environmental factors, i.e. severe weather and conditions such as fire
Answer: d. migration away from productive growing areas
Explanation:
The rice, corn and wheat are the basic food crops. These crops are used for making several dishes their flour as well as the grains of rice and corn are eaten when cooked. These three crops are necessary to be grown on large scale to meet the basic food requirements of the large growing population worldwide. The plant roughage of these three crops can be used to make biofuels. These are used as a fodder crops to feed poultry and cattles for meat harvest.
The demand will also increase when one is migrated to an unproductive region. However, the increased demand is due to decreased supply and not because of increased consumption hence, it will not directly contribute to increase in demand of crops.