In which John Green explores exactly when Rome went from being the Roman Republic to the Roman Empire. Here s a hint: it had something to do with Julius Caesar, but maybe less than you think....

In which John Green teaches you about the fall of the Roman Empire, which happened considerably later than you may have been told. While the Western Roman Empire fell to barbarians in 476 CE,...

Hank describes mitosis and cytokinesis - the series of processes our cells go through to divide into two identical copies. References: http://www.eurekalert.org/pub_releases/2012-02/wifb-amm020812...

In which John Green teaches you the history of Islam, including the revelation of the Qu ran to Muhammad, the five pillars of Islam, how the Islamic empire got its start, the Rightly Guided...

Hank gets down to the nitty-gritty about meiosis, the special type of cell division that is necessary for sexual reproduction in eukaryotic organisms. References: http://faculty.clintoncc.suny.edu...

John Green teaches you about the so-called Dark Ages, which it turns out weren t as uniformly dark as you may have been led to believe. While Europe was indeed having some issues, many other...

Hank guides us through the process of natural selection, the key mechanism of evolution. Table of Contents: 1) Natural Selection 1:27 2) Adaptation 2:56 3) Fitness 3:36 4) Four Principals...

In which John Green teaches you about the Crusades embarked upon by European Christians in the 12th and 13th centuries. Our traditional perception of the Crusades as European Colonization thinly...

Hank explains speciation - the evolutionary process by which new biological species arise - in terms of finches, ligers, mules, and dogs. Table of Contents 1) Species 0:30 2) Hybrids 1:52...

In which John is a dirty, dirty boy. Hilarious. Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse Want to find Crash Course elsewhere...

In which John Green teaches you about Sub-Saharan Africa! So, what exactly was going on there? It turns out, it was a lot of trade, converting to Islam, visits from Ibn Battuta, trade, beautiful...

Hank discusses the process by which organisms grow and develop, maintaining that, in the end, we re all just tubes. Table of Contents 1) Zygote 2:38 2) Morula 2:53 3) Blastula 3:25 4) Radial...

Hank introduces us to the relatively new field of evolutionary developmental biology, which compares the developmental processes of different organisms to determine their ancestral relationship...

Hank makes mistakes. Crash Course is on Patreon! You can support us directly by signing up at http://www.patreon.com/crashcourse Want to find Crash Course elsewhere on the internet? Facebook...

In which John Green teaches you the history of the Indian Ocean Trade. John weaves a tale of swashbuckling adventure, replete with trade in books, ivory, and timber. Along the way, John manages...

In which John Green discusses the strange and mutually beneficial relationship between a republic, the city-state of Venice, and an Empire, the Ottomans--and how studying history can help you...

Hank talks about population genetics, which helps to explain the evolution of populations over time by combing the principles of Mendel and Darwin, and by means of the Hardy-Weinberg equation....

Hank tells us the background story and explains the importance of the science of classifying living things, also known as taxonomy. References: http://anthro.palomar.edu/animal/table_kingdoms.htm...

If you re interested in learning more about the Russian government s 2022 invasion of Ukraine, check out this vlogbrothers video published on 3/15/2022: https://www.youtube.com/watch?v=mMZYKxgc9TE...

Hank gets real with us in a discussion of evolution - it s a thing, not a debate. Gene distribution changes over time, across successive generations, to give rise to diversity at every level...