Get curated editors’ picks, peeks behind the scenes, film recommendations and more.
For thousands of years before modern science-based medicine became the norm, bloodletting, frequently by leeches, was considered something of a medical cure-all. The treatment’s persistence was at least partially attributable to the Ancient Greek physician Hippocrates’ ‘four humours’ theory of disease, which held that illness was the result of an imbalance of the bodily fluids black bile, yellow bile, phlegm, and blood. With the rise of modern scientific medicine near the end of the 18th century, bloodletting leeches were relegated to the quack cabinet as doctors realised that the practice generally fixed very little, leaving patients weak and vulnerable from blood loss. But as this video from the science and nature documentary series Deep Look shows (in occasionally graphic, ultra-HD detail that is, perhaps, not for the squeamish), medical leeches have made a surprising comeback in hospitals, especially during reconstructive surgeries. Learn more about this video at the KQED Science website.
Video by KQED Science and PBS Digital Studios
Producer and Writer: Josh Cassidy
Narrator and Writer: Lauren Sommer
video
Biology
Flicker through the eclectic beauty and biological diversity of 2,400 leaves
3 minutes
video
Metaphysics
Bertrand Russell wanted to kill off causation. Can contemporary philosophy rescue it?
8 minutes
video
History of science
Bat-people on the Moon – what a famed 1835 hoax reveals about misinformation today
8 minutes
video
Biotechnology
What it’s like to wear a prosthetic that ‘feels’
6 minutes
video
Chemistry
A square inch in a Petri dish becomes a grand stage for chemical transformations
4 minutes
video
Medicine
What is it like to be a paramedic, navigating human emergency?
17 minutes
video
Physics
The tangled tale of how physicists built a groundbreaking wormhole in a lab
17 minutes
video
Computing and artificial intelligence
Teaching an AI to beat video games still takes human imagination
5 minutes
video
Social psychology
Social contagions can cause genuine illness, and TikTok may be a superspreader
10 minutes