Extinction of Dinosaurs By Jenn Collins, Meghan McCurdy, & Jen Bayer
Questions to Consider Name the theories outlining the dinosaur extinction. How long ago did the asteroid hit the earth? What are mantle plumes? Why could mantle plumes have caused the extinction of dinosaurs? What did too much CO2 result in?
Theories Asteroid Volcano Climate Change All theories are highly debated
Extinction caused by Mantle Plumes? Mantle plume: volcanic eruption that starts within the mantle Heat causes eruption on earth Up to 1,000 km in diameter Eruptions can last between 1- 2 million years
Where would it have taken place? Mantle plume eruption under Indian Ocean Found through microfossil assemblages Today activity can be seen in Iceland, Hawaii, Easter, Reunion, Tristan, Louisville, and Ethiopia
How are dinosaurs impacted? LLLLava, ashes, and gas would have effect on climate ““““Destabilized environment” causing evolution MMMMay have caused predomination of mammals
More evidence… Deccan region in India covered by lava flows Presence of iridium found in “layer” of dinosaur extinction Shocked crystals in iridium caused by explosions or eruptions only Gradual decline in # of dinosaur species… caused by volcanoes?
What happened??? Continents shifted New mountains rose Sea levels gradually dropped
What was the result? Change in the air temperature Weather pattern change New kinds of plants Colder temperature Possibly caused dinosaurs to be sluggish and less able to hunt food
Too much Carbon Dioxide resulted in: MMMMaking the climate too hot CCCChange in the weather systems and rainfall patterns DDDDecrease in the number male sperm produced, due to a warm climate which could reduce population size OOOOverheated dinosaurs
What happened to the atmosphere? HHHHigh levels of Carbon Dioxide OOOOceans became stagnant EEEExtensive volcanism and dust formation CCCChange in climate SSSSupernova Explosion CCCCompetition with other animals
Answers to Questions: Three theories are: Asteroid, Volcano & Climate Change. The asteroid hit the earth 65 mya. Mantle plumes are large volcanic eruptions that come from the mantle of the earth. Plumes casue great amounts of lava, ashes, and gas that would have had a great effect on the climate. Too much CO2 resulted in a hotter climate and a change in weather systems.