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WITH HELP OF suitable diagram represent operation of natural selection on different traits??

 Natural selection simply means that the organisms and species that survive and reproduce are the sole ancestors to the next generation of living things. Those that die or fail to reproduce will not continue. Natural selection is basically selective breeding happening naturally instead of by a breeder. 

 
 It means that nature selects which organisms survive. If their adaptations allow them to survive better in the world, then they pass on their genes to their offspring. If their adaptations don't allow this, then they starve or are killed off.
 
 

Natural selection is one of the basic mechanisms of evolution, along with mutation, migration, and genetic drift.

Darwin's grand idea of evolution by natural selection is relatively simple but often misunderstood. To find out how it works, imagine a population of beetles:

  1. There is variation in traits.
    For example, some beetles are green and some are brown.
Color variation in these beetles

  1. There is differential reproduction.
    Since the environment can't support unlimited population growth, not all individuals get to reproduce to their full potential. In this example, green beetles tend to get eaten by birds and survive to reproduce less often than brown beetles do.
Differential reproduction
  1. There is heredity.
    The surviving brown beetles have brown baby beetles because this trait has a genetic basis.
Heredity of the traits of the beetles who survive
  1. End result:
    The more advantageous trait, brown coloration, which allows the beetle to have more offspring, becomes more common in the population. If this process continues, eventually, all individuals in the population will be brown.
Eventually, the advantageous trait dominates

 

If you have variation, differential reproduction, and heredity, you will have evolution by natural selection as an outcome. It is as simple as that.

Behaviors such as birds' mating rituals, bees' wiggle dance, and humans' capacity to learn language also have genetic components and are subject to natural selection. The male blue-footed booby, shown to the right, exaggerates his foot movements to attract a mate.

In some cases, we can directly observe natural selection. Very convincing data show that the shape of finches' beaks on the Galapagos Islands has tracked weather patterns: after droughts, the finch population has deeper, stronger beaks that let them eat tougher seeds.

In other cases, human activity has led to environmental changes that have caused populations to evolve through natural selection. A striking example is that of the population of dark moths in the 19th century in England, which rose and fell in parallel to industrial pollution. These changes can often be observed and documented.

 
 
 
 
 
 
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 Biologists use the word fitness to describe how good a particular genotype is at leaving offspring in the next generation relative to how good other genotypes are at it. So if brown beetles consistently leave more offspring than green beetles because of their color, you'd say that the brown beetles had a higher fitness.

How to determine fitness in our beetle population
The brown beetles have a greater fitness relative to the green beetles.

Of course, fitness is a relative thing. A genotype's fitness depends on the environment in which the organism lives. The fittest genotype during an ice age, for example, is probably not the fittest genotype once the ice age is over.

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nice explanation:)

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 thanku :)

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