Question

Based on his observations and inferences, how did Darwin define fitness? How did he define evolution?

- fitness: the contribution an individual makes to the gene pool of the next generation, relative to the contributions of other individuals; fitness is measured as reproductive success
- The more fit members of the species produce more offspring and dominate the gene pool
- Darwin = "descent with modification", the idea that all organisms are related through descent from some unknown ancestor.
- Evolution was, as a result, defined as a gradual change in species over time.

Answer 1

Charles Darwin defined fitness as the relative ability to survive and produce fertile offspring, measured as relative fitness. Evolution was defined as 'descent with modification,' where species change over time due to natural selection, with populations adapting to their environments and potentially forming new species.

Step-by-step explanation:

Charles Darwin defined fitness as an organism's relative ability to survive and produce fertile offspring within the context of evolution by natural selection. The more an organism contributes to the next generation's gene pool, particularly in terms of fertile offspring, the higher its fitness is considered. This concept is quantifiable and known as relative fitness, crucial for researchers to predict how populations may evolve.

Darwin's definition of evolution is often summarized by the phrase "descent with modification." It encompasses the idea that species gradually change over time, with populations acquiring adaptations that provide a reproductive advantage in their environments. These changes can lead over time to the emergence of new species from common ancestors, driven by the mechanism of natural selection, where nature selects for traits that are advantageous for survival and reproduction.

Darwin understood that artificial selection could influence the traits of domestic species through selective breeding. Analogously, he proposed that natural selection could operate similarly in the wild, with environmental pressures rather than humans choosing who survived and reproduced. This process leads to populations better adapted to their environments, a cornerstone of Darwin's theory of evolution by natural selection.