The timeline you've mentioned is based on a specific interpretation of certain religious texts and is not supported by the overwhelming scientific evidence from fields such as archaeology, geology, and paleontology. The evidence clearly indicates that modern humans (Homo sapiens) have been around for much longer than 6,000 years.
Archaeologists find remains and structures that are tens of thousands of years old through various scientific methods and techniques, including:
Radiocarbon Dating: Radiocarbon dating, or carbon-14 dating, is a widely used method for dating organic materials up to around 50,000 years old. It relies on the decay of the radioactive isotope carbon-14 in organic materials like bones, charcoal, and plant remains.
Luminescence Dating: Luminescence dating techniques can date certain types of minerals, like quartz and feldspar, that have been exposed to sunlight or heat in the past. It is commonly used for dating materials ranging from hundreds to tens of thousands of years old.
Stratigraphy: Archaeologists use stratigraphy, the study of layers of soil and sediment, to determine the relative ages of artifacts and structures. Older layers are generally found deeper in the ground, and younger layers are found closer to the surface.
Relative Dating: This method involves comparing the age of one archaeological find to another to establish a relative chronological order. It doesn't provide specific years but helps archaeologists understand the sequence of events.
Dendrochronology: This technique uses tree rings to establish the age of wooden structures or objects. It is limited to the age of the oldest trees available for study but can be very precise for certain regions and time periods.
Paleomagnetism: By studying changes in the Earth's magnetic field recorded in ancient objects like clay or burnt hearths, archaeologists can sometimes determine the age of these artifacts.
Genetic Analysis: In some cases, genetic analysis of ancient human remains (DNA) can provide insights into the ancestry, migration patterns, and relationships of ancient populations.
Through these scientific methods, archaeologists have been able to establish a reliable and extensive timeline of human history, showing that our species has been on Earth for hundreds of thousands of years, with more distant human ancestors dating back millions of years. This extensive timeline is supported by evidence from numerous archaeological sites, paleontological findings, and geological records.