Week 12, Extinction

Extant

species still alive

On average species last how many years

1 million- 10 million years

5 mass extinctions

Ortivision, Devonian, Permian, Triassic, Cretaceous

End Cretaceous Mass Extinction

last of the five mass, caused by meteorite, 75% of animals and plant species went extinct, all non-avian dinos

End Ordovician Mass Extinction

affected only marine organisms

End Permian Extinction

largest mass extinction, affected marine invertebrates, insects, synapsids, and anapsids

Late Devonian Extinction

affected mainly marine organisms but alo vertebrate clades

iridium

element thats rare on earth but common in meterites

Tektites

Earthly debris that was superheated by a meteorite impact and cooled to form a natural glass

Shocked Quartz

Quartz whose internal structure has deformed due to intense pressure; known to be produced from the shockwaves of atomic blasts and meteorite impacts

Cenotes

Sinkhole formed from the collapse of limestone; a circular arrangement of these mark the rim of the Chixulub crater.

Chixulub impactor

The meteor that formed the Chicxulub crater; estimated to have been at least 10 kilometres in diameter, caused tsunamis, and extreme heat, then slowly became really cold

Deccan Traps

A large deposit of volcanic rocks in India; formed from massive volcanic eruptions 60 to 68 million years ago (during end permian age), could have been a cause of the end-permian extinction

Meteor

The visible light streak from a meteoroid entering Earth's atmosphere.

Meteorite

Pieces of debris that originated in outer space and that survive an impact with Earth.

Non-Avian Dinos

All dinos except for birds

supernova

highly energetic explosion of a star

Yucatan Peninsula

Peninsula in southeast Mexico; separates the Gulf of Mexico from the Caribbean Sea.

Champsosaur

Group of semi-aquatic diapsids with elongated snouts; lived during the Middle Jurassic to Miocene,survived permian mass extinction!

end-cretaceous meteorite hypothesis

meteorite caused mass extinction

clay layer

iridium was found in clay layer, irdium is mianloy found in meteorites so this supports the meteorite hypothesis

Why can't we get dino DNA and recreate?

DNA molecules are delicate and break down over time