Final answer:
The 6th mass extinction is termed the Holocene mass extinction, mainly caused by human activities, with significant species loss occurring since the Holocene period and potentially intensifying if current trends persist.
Step-by-step explanation:
The beginning of the 6th mass extinction is called the Holocene mass extinction.
This ongoing event is largely attributed to the activities of Homo sapiens, including habitat destruction, over exploitation of species, pollution, and the introduction of invasive species, coinciding with the expansion of European colonies since the 1500s.
Unlike the five previous mass extinctions that were caused by major geologic and climatic events, the current mass extinction is primarily a result of human actions.
Since the Holocene period began, numerous species have gone extinct, with the present rate of extinction estimated to be between 100 and 100,000 species per year.
Some scientists argue that this extinction began with early hominids in the Pleistocene, who over-hunted large mammals such as mammoths. Moving forward, in 100 years, it is projected that we could lose more than half of Earth's remaining species if current trends continue.
There are steps that can be taken to help protect biodiversity, such as using less energy and preserving habitats. It's crucial to recognize the significance of this sixth mass extinction to implement effective conservation measures.