In a population, there is generally genetic diversity. In their environment, some phenotypes may be more favorable than others (when it comes to survival). The majority of survivors possess this trait, and are able to pass it down to future generations, which will lead to a steady increase.
So as for the distasteful phenotypes, well, they decrease over time. (Since those with those traits will die off)
I guess the answer to your question is an increase or decrease, depending on the phenotype.
Phenotype means the features of an individual that you can see. So if a mutation in the phenotype happens it can be either for the better or the worse. The worse will die and not have the opportunity to pass on their traits, for example a cow that doesn't have teats, and the better will be better able to live and survive, for example a squirrels with a super nose, so they have a better chance of passing on their traits. If good traits are passed on they spread in the whole population over time.
This is a very tricky question, as natural selection can occur in many ways. Directional selection, which is a type of natural selection, will push a population in one phenotypic direction, which may be the average, or to the extremes. If you look at a specific case of natural selection, such as the finches Darwin studied when he wrote his theory of natural selection, you will find natural selection pushing for extremes in phenotype. For the finches beaks, the average size phenotype was selected against, and the birds evolved different sized beaks. This allowed different populations to co-exist, without overtaxing food sources, and also allowed the finches to adapt to their specific available food sources. Larger seeds require larger beaks to crack, etc.
As a rule, natural selection is based upon the ability of exceptional organisms to procreate and pass on their genetic material. Unless the average phenotype is superior to the extremes, it will be selected against. Simple genetics, with a Mendelian cross, would select for the average, but natural selection follows a different set of rules.
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In a population, there is generally genetic diversity. In their environment, some phenotypes may be more favorable than others (when it comes to survival). The majority of survivors possess this trait, and are able to pass it down to future generations, which will lead to a steady increase.
So as for the distasteful phenotypes, well, they decrease over time. (Since those with those traits will die off)
I guess the answer to your question is an increase or decrease, depending on the phenotype.
Phenotype means the features of an individual that you can see. So if a mutation in the phenotype happens it can be either for the better or the worse. The worse will die and not have the opportunity to pass on their traits, for example a cow that doesn't have teats, and the better will be better able to live and survive, for example a squirrels with a super nose, so they have a better chance of passing on their traits. If good traits are passed on they spread in the whole population over time.
This is a very tricky question, as natural selection can occur in many ways. Directional selection, which is a type of natural selection, will push a population in one phenotypic direction, which may be the average, or to the extremes. If you look at a specific case of natural selection, such as the finches Darwin studied when he wrote his theory of natural selection, you will find natural selection pushing for extremes in phenotype. For the finches beaks, the average size phenotype was selected against, and the birds evolved different sized beaks. This allowed different populations to co-exist, without overtaxing food sources, and also allowed the finches to adapt to their specific available food sources. Larger seeds require larger beaks to crack, etc.
As a rule, natural selection is based upon the ability of exceptional organisms to procreate and pass on their genetic material. Unless the average phenotype is superior to the extremes, it will be selected against. Simple genetics, with a Mendelian cross, would select for the average, but natural selection follows a different set of rules.