evolution, species, adaptation, natural selection, survival of the fittest, environmental changes, genetic mutations, extinction events, competition for resources, failure to reproduce, loss of habitat, climate shift, predation pressure, isolated population, genetic bottleneck, lack of variation, disease vulnerability, catastrophic events, human impact, over-specialization, Darwinian theory, biological diversity, ecosystem dynamics, selective pressure, evolutionary arms race, genetic drift, reproductive success, fossil record, evolutionary biology, scientific study.