The video is a visual teaching tool that allows one to grasp big picture concepts in a small, digestible format. It depicts the human population evolving from 1 million to 1 billion within a span of 200,000 years, and from 1 billion to 7 billion within the short period of 200 years.
Below is an HHMI BioInteractive short film on the epic voyages of Darwin and Wallace that led each to independently discover the natural origin of species and to formulate the theory of evolution by natural selection.
Many textbooks are smothered with Charles Darwin as being the “father” of natural selection, rarely mentioning Alfred Wallace at all. In scientific circles, both men are credited with arriving at natural selection theory independently.
It is important to note that their theories were not entirely identical. Darwin’s theory is more focused on individual struggle while Wallace’s tends to concern itself with populations and groups. Wallace possessed more combined field time than Darwin, and in my opinion, Wallace explored more smaller isolated lands than Darwin which led to the Wallace Line – an imaginary boundary line separating ecozones that explains the differentiation of species among groups.
There is a richer backstory to both Darwin and Wallace, but to end this blog post, be comforted in knowing that they remained friends, despite minor disagreements. For example, Darwin believed that animal breeding could demonstrate natural selection, but Wallace always disagreed, arguing that such demonstrations are examples of artificial selection rather than natural selection (Wallace was correct). The short film below highlights how both men arrived at their theories.