Odors that repel, spines, poisonous chemicals, and thorns are all considered traits that oppose natural selection.
The basic concept of natural selection is that favorable traits that are heritable become more common in successive generations of a population of organisms that reproduce, and that unfavorable traits that are heritable become less common.
Natural selection is the evolutionary mechanism proposed by Charles Darwin, who stated that the environment acts as a selector of characteristics, perpetuating the organisms best able to survive in a given place.
See more about natural selection at brainly.com/question/9830102
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