What Happened to the Dinosaurs?

February 24th, 2015

Mystery

• What do we need when we are trying to solve a mystery?

Theories

• Mammal competition• Could the mammals have outcompeted

dinosaurs for food resources?

Theories

• Lots of Volcanism• Evidence for massive beds of ancient lava

found all around the world around 65 to 70 million years ago

Theories

• Plate Tectonics• Repositioning of the world’s landmasses was

disastrous for dinosaurs. As mountains formed, ocean currents were redirected and world sea level fell

Theories

• An asteroid• Ok…but

where is theevidence?

Evidence

• In 1981 two scientists Walter and his son Luis Alvarez find a very strange layer of iridium in Italy at the Cretaceous and Paleogene periods around 65 million years ago.

• They found this same layer all overthe world.

Evidence

• Iridium is a metal that is very rare on Earth’s surface but is commonly found in asteroids

• The layer of iridium at the Cretaceous Paleogene boundary had 100 X more Iridium than normal

If There Was an Asteroid Then There Must Be…

• An impact crater

Around the Same Time (1978)…

• A scientist working for a Mexican oil company was looking for new places to drill for oil using radar

• In his searching, he found a perfectly circular ring that is 70 km (40 miles) across under the ocean.

Let’s Go Down and Test Those Rocks!

• They tested the rocks and found them to be about 65 million years old, the same time as the Cretaceous-Paleogene extinction event

How Big Was The Asteroid?

• If the size of the crater was 70 km across…that must mean that the size of the asteroid was…

So if a Rock this Big Would Hit Earth What Would Happened?

Let’s Watch a Video…

• http://www.history.com/topics/why-did-the-dinosaurs-die-out

Content Take-Away

• Dinosaurs went extinct because of more than 1 reason:

• There was climate changes because of plate tectonic movement

• Lots of volcanism• Competition by mammals • Big asteroid

impact did NOT help…

Group A Group B Group C Group D Group E

Alimatou Sandeilis Daiana Antoneta Reyson

Henood Sharna Thanya Nathi Caroline

Misha Sadia Kimby Gabriela Katerina

Khady Maisha Megany Harold

Keyzie Obniel Robert

Unison Reading Groups Section 1

Group A Group B Group C Group D Group E Group FAnam Jubayer Ramzi Mosammat Dayana

Perla Ibrahim Jennifer Seme Victoria

Smarlyn Abdullah Maridania Keny Junior

Daze Sarmad Chris Humayra Kagbe

Yanvier Abdullah Besare Kaylin

Unison Reading Groups Section 2

Team 1 Team 2 Team 3 Team 4 Team 5

Thanya Megany Sandeilis Alimatou Sharna

Caroline Katerina Zoha Henood Maisha

Gabriela Kimberly Khady Daiana Sadia

Nathi Obniel Misha Keyzie Antoneta

Reyson Robert Harold Marbelin

Scarlet

Responsibility Teams Section 1

Team 1 Team 2 Team 3 Team 4 Team 5 Team 6Smaryln Ramzi Dajana Jennifer Chris Junior

Mikauly Geovani Anam Daze Victoria Sarmad

Maridania Abdullah N. Perla Besare Kagbe Abdullah Z.

Laura Ibrahim Blendi Yanvier Kaylin Jubayer

Mosammat Seme Humayra A. Francisco Humayera Z. Sumaiya

Responsibility Teams Section 2