Final answer:
The claim that life on Earth has always existed in its current form is false. Life began billions of years ago, starting with single-celled organisms and evolving over time into the complex array of species we know today, with humans being one of the most recent additions.
Step-by-step explanation:
The statement that life on Earth has existed in its present form since the beginning of time is false. Life on Earth began about 3.5 to 4 billion years ago as single-celled organisms. Over billions of years, life evolved from simple microorganisms into the complex flora and fauna we see today. The diversity of life seen on Earth now is the result of a long evolutionary process. Even humans are a recent addition to Earth's timeline, appearing only in the last 2.5 million years and acquiring our current form about 300,000 years ago.
Over time, the origin and development of life have been crucial to Earth's history. The earliest life forms have had a significant impact on the planet's environment, leading to the Earth's coevolution with its inhabitants. This fascinating relationship between life and planet Earth is part of what modern astrobiology studies.
To understand the grand scale of Earth's history, it's useful to visualize it as a 24-hour day, where humans would have appeared only in the last minute. This perspective helps us to appreciate how recent our species is relative to the entirety of Earth's history. The evidence for life's history is found in ancient fossils such as those of blue-green algae, which are some of the oldest known on Earth.