History of life #2 Flashcards
What are some important transitions in the history of life’s evolution?
Endosymbiosis and multicellularity are key important transitions in the history of life’s evolution.
What is endosymbiosis?
Eukaryotes formed from endosymbiosis where mitochondria and chloroplasts were engulfed by larger cells.
What is multicellularity?
Multicellularity refers to the emergence of life forms consisting of multiple cells.
What is the oldest rock, and when was it formed?
The oldest rock is 3.8 billion years ago (GYA) and it was formed from the presence of water.
When did evidence of life first appear?
There is strong evidence for life at 3.4-3.5 GYA through the presence of bacteria-like microfossils and stromatolites.
What are stromatolites?
Stromatolites are microbal reefs created by cyanobacteria.
What is the significance of an O2-rich atmosphere?
An O2-rich atmosphere supported the evolution of multicellular life because it provided the necessary conditions to support it.
What is the Cambrian explosion?
The Cambrian explosion is a rapid diversification of animal life that occurred around 541 million years ago (MYA).
What are some factors that contributed to the Cambrian explosion?
Genetic and ecological factors may have contributed to the Cambrian explosion.
What are some examples of lost species from mass extinctions?
Examples of lost species include Thylacosmilus, Smilodon, Glyptodon, and Megatherium.
