The Spanish fly is a species of a beetle `
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.
I believe it is “animals and plants caanot directly use all the nitrogen found in our atmosphere”
Answer:
The North American fur trade was an industry and activity related to the acquisition, trade, exchange, and sale of animal furs in North America. Aboriginal peoples in Canada and Native Americans in the United States of various regions traded among themselves in the pre–Columbian Era. Europeans participated in the trade from the time of their arrival in the New World, extending the trade's reach to Europe. The French started trading in the 16th century, the English established trading posts on Hudson Bay in present-day Canada during the 17th century, while the Dutch had trade by the same time in New Netherland. North American fur trade was at its peak of economic importance in the 19th century, and involved the development of elaborate trade networks.
The fur trade became one of the main economic ventures in North America attracting competition among the French, British, Dutch, Spanish, and Russians. Indeed, in the early history of the United States, capitalizing on this trade, and removing the British stranglehold over it, was seen as a major economic objective. Many Native American societies across the continent came to depend on the fur trade as their primary source of income. By the mid-1800s changing fashions in Europe brought about a collapse in fur prices. The American Fur Company and some other companies failed. Many Native communities were plunged into long-term poverty and consequently lost much of the political influence they once had.
Explanation:
Answer:
The correct answer is b. must be present in a population before natural selection can act upon the population
Explanation:
Genetic variation can be caused by mutation, recombination between chromosomes during meiosis and by fusion of two genetically different gametes during sexual reproduction.
This genetic variation is necessary for the evolution of any population. Natural selection acts on every individual and it decreases the frequency of those alleles that are not suited for the environment and increase the frequency of those alleles which helps the individual to survive in the changing environment.
Therefore genetic variation must be present in the population before natural selection act on the.
