7.1 How it all began

• Biologie
• biology
• Middelbare school
• vwo
• Leerjaar 3

odd one out 

what do they have in common? 

00:55

what are the two basic ideas of Darwin's theory of evolution?

Inference 2

DIFFERENTIAL

SURVIVAL &  

REPRODUCTION

natural selection 

--> every individual is unique

--> differences in traits  are inheritable 

---> 1.  variation in inheritable traits 

i.e. there are green and brown beetles 

---> differential survival & reproduction 

i.e. green beetles tend to get eaten by birds and survive to reproduce less often than brown beetles

and 

surviving brown beetles have brown baby

beetles 

--> final result 

i.e. the more advantageous brown colouration which allows the brown beetle to have more offspring becomes more common in the beetle population. 

If this process continues, eventually, all individuals in the population will be brown 

GIf you have  --------> natural selection ---> EVOLUTION! 

- variation, 

- differential survival & reproduction = survival of the fittest

- heredity

fernandina

-> small fruit

santiago/san salvador

--> small seed

santa cruz

--> worms

pinta

--> large fruit

fernandina

-> small fruit

santiago/san salvador

--> small seed

santa cruz

--> worms

pinta

--> large fruit

Inference 2

DIFFERENTIAL

SURVIVAL &  

REPRODUCTION

7. An epic journey 

Benodigheden

- iPad

- Pen, pencil

- note book

- binder

For a mark

- No

Lessonup

- Yes

Bags

in bag closet

Phones 

in phone closet

today''s program 

revision 'evolution' 

learning objectives: you can 

• tell the difference between the different types of adaptations
• compare the theories of Lamarck and Darwin 
• explain how different species are formed
• how fossils als formed 

complete the following sentences

1. Evolution occurs through n.......... s........
   
2. Individual organisms show v__________.
3. Many die by predation, disease and c---------
4. Individuals most suited to the environment survive to breed – ‘su______l of the fi_______t.
5. The genes that help the individual survive are passed on to the of_________g.

apply the evolution theory to explain..

why polar bears wear a white fur.

different types of adaptations

structural:  

      changes of body parts 

      mimicry : a species resembles another species 

physiological: 

      changes in cell metabolism

--> what type of changes do you see in the next video? 

• If you cut off a rat’s tail will its babies have no tail?  
  
• If I straighten my hair every day is there a chance that my children will have straight hair? 

Darwin vs Lamarck (copy this!)

Darwin: 

• natural selection of inherited traits
  

Lamarck: 

• use and disuse : individuals lose characteristics they do not require and develop the ones that are useful
  
• inheritance of acquired traits : individuals inherit the traits their ancestors acquired during their lifetimes 
  

How might Darwin and Lamarck have explained the ability of birds of prey to fly very fast?

How might Darwin have explained the ability of birds of prey to fly very fast?

• Birds of prey need to fly fast to catch prey
• Within the bird of prey species, some individuals can fly faster than others. These faster birds catch more food, do better and have more offspring. Such offspring, at least to some extent, inherit their parents ability.
• Over the generations with fast flying prey, the birds evolve the ability to fly very fast 

How might Lamarck have explained the ability of birds of prey to fly very fast?

• Birds of prey need to fly fast to catch prey
  
• Over their life time, birds develop the appropriate large flight muscles and other key features to pass on, at least to some extent, to their offspring that will be born with these traits
• Over the generations with fast flying prey, the birds evolve the ability to fly very fast 

how different species are formed?

by reproductive isolation 

-allopatric

-sympatric 

--> what's the difference?

allopatric: 

homework

lrn par. 7.1 

read par. 7.2, do q. 1-4