What caused the ice ages? One thing that contributed to the ice ages was the positioning of the continents.  When the continents blocked the warm water flow from the equator to the poles - it created cold areas that were snowed on and then couldn’t warm up - forming glaciers. Another contributor is the Milankovitch cycles - these are changes in the Earth’s orbit, rotation, and axis tilt that causes the climate to change (over the course of many years) https://www.youtube.com/watch?v=iA788usYNWA There were 5 major ice ages:   the Huronian (2.4-2.1 billion years ago) Cryogenian (850-635 million years ago) Andean-Saharan (460-430 mya) Karoo (360-260 mya)  Quaternary (2.6 mya-present) Ice Age video: https://www.youtube.com/watch?v=dJ5GYQrkvxI Uh - Quaternary said 2.6 mya to present...present - like now? Yes - very true - but our overall temperature is up (and increasing due to climate change) and we have been pretty well out of it since 12,000 BCE. Let’s listen to an expert (don’t worry

 "Let's Start at the Very Beginning - a Very Good Place to Start!" This is the Chauvet Cave in Ardèche, France dated from 30,000-28,000 BC; it is a pictograph of lions Have you ever seen those cave paintings... Fancy right?  While true written language didn’t really happen until 3000 BCE or so - we have “cave paintings” or pictographs (painted) and petroglyphs (carved) to look at.  We take this info - combine it with lots of others (skeletons etc) and we get a hazy picture of early man.  He certainly wasn’t a pretty boy…. https://www.britannica.com/video/194292/Homo-species-debates-human Something else to explore:  https://humanorigins.si.edu/evidence/human-fossils/species?sort_by=field_age_timeline_maximum_value There were a lot of these early “humans”... The different varieties of humans lived from 3.3 million years ago to the end of the glaciers - which was called the Pleistocene epoch (era).  This means that they co-existed with mammoths, Canadian camels and elephants