Many species which existed in the past are now extinct. They became extinct either because their environment changed or because a different species was better adapted to their niche than they were. Brown bears are now extinct in Ireland. Scientists think that changes in their habitat that occurred during the last ice age caused their extinction.
Fig. 10 Brown bears are extinct in Ireland. Nature of Science
This cartoon was published in an English magazine in 1871. It portrays Charles Darwin as an ape and was intended to make fun of Darwin and his ideas about evolution. The media often interpret and comment on scientific ideas. 1. Do you think that media reporting on scientific ideas is always fair?
2. Why do you think that people sometimes misinterpret scientific ideas?
3. What role do scientists play in helping people to understand their ideas properly?
Chapter Summary
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Evolution is the process of change in the general characteristics of a species. Natural selection is the process whereby organisms that are better adapted to their environment tend to survive and produce more offspring. Variation is the difference between the individuals in a species. Inheritable characteristics are controlled by genes and can be passed directly from parents to offspring. An adaptation is a characteristic that improves the chances of an organism surviving and reproducing.
