Answer:
An allele is a diffrent form of genes
Yes, It seems that evolution has occurred in this area.
Explanation:
Evolution refers to a phenomena in which new traits or alleles that favor a better survival of organisms in a given environment, become fixed in the population.
Evolution is characterized by appearance of new characters and change in allele frequencies.
In the given situation we find that the frequency of the recessive allele in the population has changed over time and the percentage has become fixed.
So, we can say that evolution has occurred in the robin population
<span>heterozygous for the trait and able</span>
Answer:
Upwelling
Explanation:
Upwelling is the process through which cold water gets to ascends from the bottom, providing nutrients to the superficial stratum.
Upwelling is an ascending displacement of marine currents. The phenomenon<em> can also occur in lakes or freshwater dams</em>.
Wind blowing over the coast can cause surface water to move out to sea. This motion is complemented by a slow ascension of cold water coming from the bottom forward to the coast. This currents movement is known as upwelling.
Upwelling water is extremely cold and rich in nutrients, which result from remineralization, by bacterial action, of organic matter that accumulates in the deepest stratum of the water body.
The contact of minerals with photosynthesizing organisms in superficial layers produces a significantly high primary productivity.
