What is the process of evolution?

The process of evolution is fundamentally defined as a change in heritable traits of populations over generations. This encompasses the mechanisms by which populations of organisms undergo genetic changes over time, often in response to environmental pressures, natural selection, mutations, and genetic drift. Evolution leads to adaptations in species that improve their chances of survival and reproduction in their specific environments.

When we consider options related to evolution, the distinction of heritable traits is crucial because evolution operates at the population level rather than affecting individual organisms directly. Individual organisms may change during their lifetimes due to environmental factors or personal experiences, but these changes are not passed on to their offspring; thus, they are not considered evolution in the biological sense. True evolutionary changes involve alterations in the genetic makeup of a population over many generations, which can lead to the emergence of new species.

The notion of modification of ecosystems over time does occur through various processes including evolutionary changes, but it doesn’t directly define evolution itself. Additionally, while environmental changes may affect species survival, they are part of the broader context in which evolution occurs rather than a definition of the process. Therefore, the correct understanding of evolution hinges on recognizing the significance of heritable traits and their transmission across generations within populations.