Why aren't Neanderthals considered humans?

 The classification of Neanderthals as a separate species from modern humans (Homo sapiens) is a result of the scientific understanding of taxonomy and evolutionary relationships. Neanderthals (Homo neanderthalensis) were a distinct hominin species that lived in Europe and parts of Asia from about 400,000 to 40,000 years ago, overlapping with the existence of anatomically modern humans.

The primary reasons Neanderthals are considered a separate species from Homo sapiens include:

1. **Distinct Morphology:** Neanderthals had certain physical characteristics that distinguished them from anatomically modern humans. These features included a robust build, a larger brow ridge, a more prominent nose, and a different shape of the skull.

2. **Genetic Differences:** While Neanderthals and modern humans share a common ancestry, genetic studies have shown that they are a separate branch on the human family tree. Some interbreeding occurred between Neanderthals and early Homo sapiens, as evidenced by traces of Neanderthal DNA in the genomes of non-African modern human populations. However, the degree of genetic separation supports the classification of Neanderthals as a distinct species.

3. **Behavioral and Cultural Differences:** Neanderthals exhibited certain behaviors and cultural traits that were distinct from those of early modern humans. While there is evidence of symbolic thinking, burial practices, and tool use among Neanderthals, their cultural expression was not identical to that of contemporary Homo sapiens.

It's important to note that the classification of species in paleoanthropology can be complex, and the lines between species are not always clear-cut. The distinction between Neanderthals and modern humans is based on a combination of anatomical, genetic, and archaeological evidence. However, as scientific methods and discoveries continue to advance, our understanding of these ancient populations may be refined.