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Natural Selection
Natural selection is a function of evolution. It involves biological traits becoming more or less prominent depending on the needs and environment of a specific species.
666 Questions
Was it absolutely necessary for natural selection to take place?
Genetic change is necessary for natural selection to take place
Pure line selection involves choosing and breeding individuals within a population that display desirable traits to establish a genetically homogenous line that consistently exhibits those traits. This method is commonly used in plant and animal breeding to develop stable and uniform varieties with specific characteristics.
Which of the following steps in the selection process is usually the most heavily Weighted?
screening interviews
Why are structures not removed by natural selection?
Vestigial structures do not harm the organism. Nature selects against only harmful traits.
What can be used to describe evolution by natural selection?
The term that is often incorrectly used to describe evolution by natural selection is "survival of the fittest."
Is horse breeding an example of natural selection?
Yes, and no. Natural selection usually refers to a situation wherein alleles or organisms compete against eachother without external guidance, under the influence of mindless environmental factors.
In horse breeding, the principle is almost exactly the same, but the factors influencing the differential reproductive success of alleles include the intelligent decisions of humans.
What is the main contribution of neo darwinians to theory of darwinism?
By linking genetics and systematic biology in one synthesis the neo-darwinians showed, mathematically, that natural selection could account for adaptive change in organisms and the evolution of populations over time. This was the beginning of population genetics.
What’s is the theory of natural selection?
The non-random survival of randomly varying replicators.
According to Richard Dawkins.
What is the Meaning of natrul selection?
It is the most consistent, and perhaps the best, theory put forward to explain the fact of evolution.
How might natural selection on a single gene traits lead to evolution?
The theory of evolution by natural selection, first formulated in Darwin's book "On the Origin of Species" in 1859, is the process by which organisms change over time as a result of changes in heritable physical or behavioral traits.
Changes that allow an organism to better adapt to its environment will help it survive and have more offspring. The theory is sometimes described as "survival of the fittest," but that can be misleading. Here, "fitness" refers not to an organism's strength or athletic ability, but rather the ability to survive and reproduce.
Mutations can be caused by random errors in DNA replication or repair, or by chemical or radiation damage. Most times, mutations are either harmful or neutral, but in rare instances, a mutation might prove beneficial to the organism. If so, it will become more prevalent in the next generation and spread throughout the population.
In this way, natural selection guides the evolutionary process, preserving and adding up the beneficial mutations and rejecting the bad ones. Mutations are random, but selection for them is not random.
How can natural selection lead to regression?
In the genetic sense, it can't. Evolution really has one direction, and one direction only: forward. However, evolution may cause organisms to evolve traits that resemble traits of some of their precursors. For instance, whales are sea-mammals that descended from land-mammals, which in turn evolved from earlier aquatic organisms like fish. But due to the demands of their environment, whales evolved an overall morphology that resembles those of these earlier fish.
Why is DNA used as evidence in natural selection?
Mathematical analysis in genetics and comparative genomics can show scientists to what degree a particular genetic sequence resulted from selection pressures at a given time in the evolutionary history of the organism under consideration.
How does natural selection lead to antibiotic resistance in bacteria?
The bacteria who (for whatever reason) happen to be better able to withstand antibiotics are the ones who usually survive long enough to reproduce. Their offspring, therefore, are more likely to have that little bit of better resistance that gives them those few seconds of advantage, etc. Usually it'd take a long time for that little difference to make a creature resistant to a toxin, but as bacteria have a very fast reproduction rate you have thousands of generations in a really short time.
A hundred years may not seem like really fast to us, but considering these kinds of changes in more complex life forms would take millions of years, that's like evolution on fast forward (take humans for example: 10,000 years later and the only thing that's changed is our environment - our Biology is still pretty much the exact same as before).
What is natural selection and what are the basic components?
Natural selection is the non-random differential reproductive success of variant traits. The process has no components per sé. It does, however, rely on a few key conditions, assumed to be present in all life. The assumptions it rests upon are:
- That life reproduces with variation in inherited traits.
- That a population always produces slightly more offspring than can comfortably subsist in its niche.
- That offspring therefore, directly or indirectly, compete for resources and mating opportunities.
- That differences in inherited traits affect the average number of fertile offspring raised by individuals.
- That traits that allow their bearers to raise a higher average number of fertile offspring spread throughout the population faster than rival traits.
