You're asking about the order of appearance of human species on Earth, which is a topic within the study of human evolution. Here's a simplified timeline, focusing on the major groups:

1. Australopithecus afarensis (Lucy): 3.9-2.9 million years ago (mya)

2. Australopithecus africanus: 3.3-2.1 mya

3. Paranthropus boisei: 2.3-1.2 mya

4. Homo habilis: 2.4-1.6 mya

5. Homo erectus: 1.8 million - 117,000 years ago

6. Homo neanderthalensis (Neanderthals): 400,000 - 40,000 years ago

7. Homo sapiens (Modern Humans): 300,000 years ago to present

Key Points

* Early Hominins: The earliest species, like Australopithecus, are often called "hominins" rather than "humans." While they walked upright and had some human-like features, they were different enough to be considered a separate group.

* Homo genus: The genus "Homo" is where we find our direct ancestors, including Homo habilis, Homo erectus, and ultimately, Homo sapiens.

* Coexistence: Several human species coexisted at different times, and there's evidence of interbreeding between Neanderthals and Homo sapiens.

Note: This is a simplified overview. The field of human evolution is constantly evolving, and new discoveries are made all the time.