Summed Up in About 10 Minutes

 The Big Bang occurs and the universe is formed  The universe continually expands, as matter cools galaxies of stars and planets form  Thought to be about 13.7 billion years ago

 About 13.2 billion years go  Today consists of million stars  Probably at least 10 billion planets considered a livable distance from a sun

 About 4.57 billion years  A supernova causes shockwaves which forces clouds of gas together  It’s incredible mass and gravity cause fusion reactions to occur- releasing lots of light and heat

 About 4.54 billion years ago  Leftover gases and dusts come together forming planets  Only took million years  Moon forms about 4.53 billion years ago

 Had no oxygen  Was very hot and molten, but slowly began to cool  Volcanoes spewed gases into the air, forming a primitive atmosphere  Meteor/asteroid strikes were common

 About 4.4 billion years ago  The earth had cooled enough for water to condense  Thought to be where life first began

 UV radiation and lightening hitting simple gases was able to form complex molecules like:  Nucleotides  Proteins  Carbohydrates  Proved to be possible – we can do this in a lab!  Some alien molecules landed with asteroids?????

 We really don’t know, but believe it was about billion years ago  This is where things get very hypothetical, there are a few models, each which have some evidence supporting them and some flaws  This is NOT ADDRESSED by Darwin or Evolution

 Self-replicating molecules must have formed  Thought to possibly be RNA?  Metabolism must have evolved  First life could manipulate its environment?  Membranes must have evolved  Lipids were first form of life?  Some combination of above 3?  Clay model?

 There is strong evidence that all life shares a single common ancestor  Evidence also suggests that it was a heterotrophic prokaryote  No organelles, no photosynthesis

 Last Universal Common Ancestor  DNA as code  RNA as code carrier  Ribosomes as protein factories  Amino acids/proteins  Cell membranes

 In bacteria-like simple organisms about 3.3 billion years ago  Produced oxygen which led to the ozone layer  Also led to the evolution of aerobic cellular respiration

 About billion years ago  At some point we think one cell engulfed a photosynthetic bacteria – forming a cell with a chloroplast  Same thing happened to create mitochondria

 About 1 billion years ago  Probably has happened several times  Colonies of single cells came together??

 About 600 million years ago in water  Simple sponge- like creatures

 About 475 million years ago  Provide food on land  Insects follow about 75 million years later

 About 350 million years ago  A population of fish was able to survive on land for longer and longer periods of time over many generations

 About 200 million years ago (about 100 million years after reptiles, 50 million years before birds, 70 million years before flowers)  Were around with the dinosaurs

 About 55 million years ago  Thought to be small, the size of a squirrel

 About 2.5 million years ago  Which exact species are the ancestor not well understood

 About 200,000 years ago  About 0.004% of Earth’s existence, 0.005% of the time life has existed, and 0.03% of the time animals have existed  We have been around for a very short time (relatively)