Eep discovers fire for the first time. Fire allowed humans to fight, stay warm, consume healthier foods with more nutrients, and ultimately survive. Fire is one of the first discoveries that distinguished humans from other animals.
Guy helps the family of The Croods to walk on some pointy plants due to his invention (the shoes), a tool that they will use for the first time in their lives.
Beakman explains what a microscope does and then dresses up like Zacharias Janssen, the compound microscope inventor. He shows how Leewenhoek basically created a magnifying glass but Janssen expanded upon it by adding the second lense to make a compound microscope. Beakman then shows a variety of slide samples under the microscope and explains it's an important scientific tool.
The Croods behave like Neanderthals in comparison to Guy, who is a Homo Sapiens. Guy mentions their sloping foreheads and extreme body hair, both of which set Neanderthals apart from Homo Sapiens. This clip also teaches that only Homo Sapiens have mastered fire, which set them apart from Neanderthals.