Lecture 6 Flashcards
Which of the following statements about human evolution is incorrect?
humans evolved from chimpanzees
What is the evidence that an impact of a large (10-15km) sized asteroid caused the K-T mass extinction?
We first found a global layer of iridium and soot, and later a large crater that formed at that time
What was the significance of the K-T event for mammals?
they rapidly diversified to fill the ecological niches that were suddenly available
the fact that modern humans evolved from chimpanzees is:
Is wrong, both species evolved from a common ancestor millions of years ago
the closest living relative to a Chimpanzee in the animal domain is:
I am (homo sapiens)
What is an extremophile?
An organism that thrives in conditions that would be lethal to humans and other animals (or even microbes)
what is the importance of the discovery of extremophiles to astrobiology?
It shows that life can adapt to surprisingly extreme conditions which are similar to conditions that exist on other bodies in the solar system
What was the earliest life on Earth?
Microbes (Chemoautotrophs)
When did photosynthesis evolve?
3.2 billion years ago - 3.5 billion years ago
The buildup of oxygen in our atmosphere
Photosynthesis developed: aerobic(using H2O and oxygen) by blue-green algae
Oxygen buildup was slow
Great Oxidation Event
- many species of microbes became extinct
- only organisms that can handle oxygen flourished
- Oxygen based metabolism provides more energy
The colonization of land
- complex life only aquatic until protective ozone layer formed
- first land based plants evolved from algae: 450 – 500 Myrs ago
- Within 75 Myrs animals followed plants (food) on land
List major mass extinction events
- Late Ordovician
- Late Devonian
- End Permian
- Late Triassic
- K-T Event
Which mass extinction event killed the dinosaurs
K-T Event
How much of our genes do we share with chimpanzees
> 98%
