Atheism, by definition, is the lack of belief in the existence of gods or deities. It is not a belief system or a specific worldview, but rather a position on the question of the existence of gods. As such, atheists may have different perspectives on the origin of humans based on their individual beliefs, scientific understanding, and personal philosophies.
The most common and widely accepted scientific explanation for the origin of humans is the theory of evolution. According to this scientific theory, humans, like all living organisms, have evolved over millions of years through a process of natural selection and genetic variation. The theory of evolution is based on substantial evidence from various fields of science, such as paleontology, genetics, comparative anatomy, and molecular biology.
According to the theory of evolution, humans share a common ancestry with other primates, such as chimpanzees and bonobos. Through a long process of natural selection, genetic mutations, and adaptation to changing environments, our early ancestors evolved into the species known as Homo sapiens (modern humans) around 200,000 years ago.
Atheists who accept the scientific consensus on evolution would generally subscribe to this explanation for the origin of humans. It's important to note that atheists, like any group of people, can have diverse opinions, and there might be individual variations in their views on this topic. Some atheists may be more interested in scientific explanations, while others might have alternative views on human origins based on other philosophical, anthropological, or historical perspectives.