To become a professor in anthropology, can I get my PhD from a university in the UK and still have it be on the same level as a PhD from the US? So ultimately I want to become a professor in Anthropology, but I want to get my degree ASAP. The UK has degree programs that run 3-4 years and the US its mostly 5-7. Are UK PhD programs, especially in anthropology, regarded the same as US PhD programs.
Most UK doctorates make more assumptions about your prior preparation within your specialty than do those in the US. But they end up at the same place - qualified researchers who have proved themselves through research worthy of publication. 

There should be no difference. Also, anthropology is well established in UK and has a very long history. 

The UK degree likely requires fewer if any courses prior to beginning research. 

In the US you can start a doctorate immediately after undergraduate school and the undergraduate degree is a generalist one here, with much less specialization and research.