5.5 : History of life

• Biologie
• Middelbare school
• vwo
• Leerjaar 3

BS 5 - History of life

Learning objectives

You can explain how fossils arose.

You can explain that species are related if they have a common ancestor

Video assignment

You will hear different ways of how fossils were created. Write them all in your notebook!

Fossils

1. Created when remains of organisms do not decay
   
2. Deposited layers of clay or sand cover the remains
   
3. Bacteria unable to do their work - the process of decay is stopped
   
4. Other layers of sand/clay cover the remains and over time mineralize
   

Video assingment. Write the questions in your notebook

Which organisms can live in an oxygen-free environment?

Which organisms create oxygen?

How did multicellular organisms arise?

What led to the evolutionary spurt?

https://npo.nl/npo3/dwdd-university-presenteert/09-12-2016/VARA_101381430

Geological timescale

• Geological time scale: Division of the     Earth's history into geological eras.
• Life on Earth evolved in these eras.
• Each era is divided into periods. 
• Periods can be divided into time slots
• Numbers indicate time in millions of years ago.
  
• You can see how many million years ago a period started and ended.

Animals on land

1. First land plants = 500 mya
   
2. Fish appeared around the same time
   
3. First land animals = 450 mya
   
4. Arthropods (centipedes in particular)
   
5. Followed by amphibians and reptiles
   
6. Reptiles were quite successful = dinosaurs  251 mya
7. First mammals and birds appeared alongside dino
   
8. Dinos wiped out 65 mya
   
9. Meteor collision with earth - Created black cloud of dust that hung over the earth’s surface for years
10. Darkened the sky = temp dropped = climate change
11. Hominids appeared 3 mya
    
12. Homo sapiens appeared 150,000 years ago

Video assignment

Write down in your notebook during the video:

A rudimentary (vestigial) organ = ....

Rudimentary organs

Let's work!

Make question 1, 2,3, 5, 7, and 9