Final answer:
The main difference between extant and extinct species is existence; extant species are still living while extinct species have died out completely. Human activities have greatly accelerated current extinction rates, potentially leading to a sixth mass extinction.
Step-by-step explanation:
Difference Between Extant and Extinct Species
The terms extant and extinct refer to the current existence status of species. An extant species is one that is still alive and has a population that exists in the wild or can be found in captivity. These species can be observed and studied in their natural environment or in zoological parks. On the other hand, an extinct species is one where all individuals of that species have died out, and no living members remain, either in the wild or captivity. Thus, extinct species are no longer a part of the Earth's biodiversity.
The cichlids of Lake Victoria are an example that highlights the rapid species loss happening globally due to human activities. The fossil record displays periods of mass extinctions, where high rates of species loss occurred. Today's high species extinction rates are comparable to these past events but are driven significantly by human actions such as habitat destruction, introduction of exotic species, and overharvesting. The International Union for Conservation of Nature (IUCN) provides data on extinct and endangered species, emphasizing the importance of preserving biodiversity.
Current extinction rates are reported to be up to 500 times greater than the background extinction rates previously recorded in Earth's history without significant geological or climatic events. This unprecedented rate of species loss indicates that we are likely experiencing a sixth mass extinction period, largely attributed to human influence rather than natural events. The predicted loss within the next century ranges from 10 to 50 percent of species, which will significantly impact the planet's biodiversity.
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