In population genetics, directional selection is a mode of natural selection in which an extreme phenotype is favored over other phenotype, causing the allele frequency to shift over time in the direction of that phenotype
1) As blood groups A and B are equally dominant so the individual will express both characteristics in the phenotype.
Notice how in all the 3 other examples the organism is only expensive 1 version (allele) of each gene. For example the mouse with brown fur may have 2 brown fur alleles (and so would have to express this characteristic even if it was recessive) but it could have 1 allele which is less dominant than the brown, in which case brown would be expressed. In this case the alleles were not co-dominant.
<span>The answer is Monarch butterflies migrating southward. This describes the innate animal behavior, </span>Monarch Butterflies perform one of the longest migration known in insects. Starting from North America, they spend their summer in North America, and migrate south to Mexico for the winter.<span>
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Hey there!
There are two genders known to science, male and female. People nowadays have the ability to alter their gender, but in the end, there are really only two.
I hope this helps!
There are different types of observers. Casual observers differ from scientific observer. Seeing and observing are two different things. Not that everybody seeing is actually observing the thing.
A casual observer just sits back and watch for something to happen while a scientific observer comes up with some hypothesis to work on it.